BORRELIA-BAKTEERIN OMINAISUUKSIA

Asiantuntijana Soile Juvonen TTT

Valvojat: Bb, Sailairina, maranoma, Tiina

BORRELIA-BAKTEERIN OMINAISUUKSIA

ViestiKirjoittaja soijuv » To Tammi 22, 2009 21:10

Joidenkin näkemyksen mukaan Borreliabakteeri liikkuu ainoastaan solujen ulkopuolella. Miklossyn (2005) tutkimuksissa bakteerin osoitettiin tunkeutuvan esim. neuronien ja muiden keskushermoston solujen sisään. Jo vuonna 1991 Ma ym. osoittivat bakteerin tunkeutuvan verisuonten seinämissä olevien endoteelisolujen sisään.

Intracellular Residence of Borrelia within Neurons and Central Nervous System Cells (human)
From the manuscripts of Judith Miklosssy MD PhD

Dr Judith Miklosssy has demonstrated ( with the use of specific Monoclonal antibodies to Borrelia
species (OSP A) that intradellular forms of Borrelia are present within diseased Human tissues:

From her PhD thesis in 2005 Figure

http://www.miklossy.ch/media/83fcb06de3 ... a86321.pdf


From her PhD thesis in 2008: (fiure 7 i) (figure 7h)

http://www.ncbi.nlm.nih.gov/pmc/article ... 4-5-40.pdf

http://www.ncbi.nlm.nih.gov/pmc/article ... 4-5-40.pdf

Attachments

Choroid plexus cell with spirochete - Miklosssy 2008 Fig 7.jpg
Human Choroid plexus cell (Figure 7h)
Choroid plexus cell with spirochete - Miklosssy 2008 Fig 7.jpg (19.51 KiB)

Miklossy 2008 Intracellular spirochete cortical neuron Immunostain(arrow)Fig7.jpg
Human Cortical Pyramidal neuron - Intracellular borrelia -immunostain OspA (Figure 71)
Miklossy 2008 Intracellular spirochete cortical neuron Immunostain(arrow)Fig7.jpg (12.62 KiB)

Miklossy Rat Neuron with Intracellular Borrelia Fig7 i.jpg
Intracellular Borrelia within a Rat Neuron( Figure )
Miklossy Rat Neuron with Intracellular Borrelia Fig7 i.jpg (4.5 KiB)
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Infect Immun. 1991 February; 59(2): 671–678.
PMCID: PMC257809
Intracellular localization of Borrelia burgdorferi within human endothelial cells.

Y Ma, A Sturrock, and J J Weis
Author information ► Copyright and License information ►
This article has been cited by other articles in PMC.
Abstract

The later stages of infection by the Lyme disease pathogen, Borrelia burgdorferi, are characterized by the persistence of the organism in individuals possessing a strong anti-Borrelia immune response. This suggests that the organism is sequestered in a tissue protected from the immune system of the host or there is a reservoir of the organism residing within the cells of the host. In this report, the ability of B. burgdorferi to gain entrance into human umbilical vein endothelial cells was explored as a model for invasion. Incubation of B. burgdorferi with human umbilical vein endothelial cells at ratios ranging from 200:1 to 5,000:1 resulted in the intracellular localization of 10 to 25% of B. burgdorferi in 24 h. The intracellular location of the spirochetes was demonstrated by the incorporation of radiolabeled B. burgdorferi into a trypsin-resistant compartment and was confirmed by double-immunofluorescence staining which differentiated intracellular from extracellular organisms. Actin-containing microfilaments were required for the intracellular localization, indicating that the host cell participates in the internalization process. Activation of endothelial cells by agents known to increase the expression of several adhesion molecules had no effect on the interaction of B. burgdorferi with the endothelial monolayer. This indicates that the endothelial receptor for B. burgdorferi is constitutively expressed and that internalization is not dependent upon adhesion molecules whose expression is induced by inflammatory mediators. The demonstration of B. burgdorferi within endothelial cells suggest that intracellular localization may be a potential mechanism by which the organism escapes from the immune response of the host and may contribute to persistence of the organism during the later stages of Lyme disease.
Full text
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Borreliabakteeri kykenee pakenemaan immuunijärjestelmän tuhoamisyrityksiä mm. sitomalla elimistön komplementtien säätelijöitä ja estämällä siten komplementtien aktivoitumisen. Borrelioosin aiheuttamat neuro-psykologiset syyt ovat vielä selvittämättä. Yhdeksi syyksi on epäilty infektion aiheuttamia neuro-hormonaalisia häiriöitä.


http://www.ncbi.nlm.nih.gov/entrez/quer ... &DB=pubmed

Przegl Epidemiol. 2006;60 Suppl 1:167-70.

New aspects of pathogenesis of Lyme borreliosis
[Article in Polish]

* Zajkowska J,
* Grygorczuk S,
* Kondrusik M,
* Pancewicz S,
* Hermanowska-Szpakowicz T.

Klinika Chorob Zakaznych i Neuroinfekcji AM w Bialymstoku.

B. burgdorferi can evade the destructive effects of the immune system by binding host's complement regulators, which leads to inhibition of the complement activation cascade. Complement activity is blocked by CRASPs--complement regulator acquiring surface proteins. Complement resistance might therefore represent one major pathogenic factor favoring spirochete transmission to the vertebrate host, as well as determine host reservoirs of Borrelia burgdorferi genospecies. The cause of neuro-psychiatric disorders developing in some patients with Lyme borreliosis is still unknown. One of the hypotheses links them to neuro-hormonal disturbances induced by B. burgdorferi infection.

PMID: 16909797 [PubMed - in process]
Viimeksi muokannut soijuv päivämäärä Ke Huhti 18, 2012 20:24, muokattu yhteensä 3 kertaa
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ViestiKirjoittaja soijuv » To Tammi 22, 2009 22:23

Tutkimuksen mukaan borreliabakteerit kykenevät tunkeutumaan hermo-/hermotukisolujen sisään. Tunkeutumalla hermosolujen sisälle borreliabakteeri selviytyy immuunijärjestelmän tuhoamisyrityksiltä ja kykenee aiheuttamaan tuhoa keskushermostossa.


Microbes & Infection 2006 Sep 22; [Epub ahead of print]

Invasion of human neuronal and glial cells by an infectious strain of Borrelia burgdorferi.

* Livengood JA,
* Gilmore RD Jr.

Centers for Disease Control and Prevention, Division of Vector-borne Infectious Diseases, 3150 Rampart Road, CSU Foothills Campus, Fort Collins, CO 80522, USA.

Human infection by Borrelia burgdorferi, the etiological agent for Lyme disease, can result in serious acute and late-term disorders including neuroborreliosis, a degenerative condition of the peripheral and central nervous systems.

To examine the mechanisms involved in the cellular pathogenesis of neuroborreliosis, we investigated the ability of B. burgdorferi to attach to and/or invade a panel of human neuroglial and cortical neuronal cells.

In all neural cells tested, we observed B. burgdorferi in association with the cell by confocal microscopy.

Further analysis by differential immunofluorescent staining of external and internal organisms, and a gentamicin protection assay demonstrated an intracellular localization of B. burgdorferi.

A non-infectious strain of B. burgdorferi was attenuated in its ability to associate with these neural cells, suggesting that a specific borrelial factor related to cellular infectivity was responsible for the association.

Cytopathic effects were not observed following infection of these cell lines with B. burgdorferi, and internalized spirochetes were found to be viable.

Invasion of neural cells by B. burgdorferi provides a putative mechanism for the organism to avoid the host's immune response while potentially causing functional damage to neural cells during infection of the CNS.

PMID: 17045505
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ViestiKirjoittaja soijuv » Pe Tammi 23, 2009 21:16

Punkin sylki edesauttaa borreliabakteerin nopeaa lisääntymistä
ja leviämistä elimistöön sekä punkkeihin.


Int J Med Microbiol. 2009 Jan 13; [Epub ahead of print]

Tick saliva affects both proliferation and distribution of Borrelia burgdorferi
spirochetes in mouse organs and increases transmission of spirochetes to ticks.

Horka H, Cerna-Kyckova K, Skallova A, Kopecky J.

Laboratory of Vector-Host Interactions, Institute of Parasitology, Biology
Centre AS CR, Faculty of Science, University of South Bohemia, Branisovska 31,
370 05 Ceske Budejovice, Czech Republic.

Ixodes ricinus tick saliva-activated transmission of Borrelia burgdorferi sensu
stricto spirochetes was studied on the C3H/HeN mouse model. The influence of the
feeding of uninfected nymphs on the proliferation and distribution of
intradermally inoculated spirochetes was compared with the effect of
co-inoculated saliva or salivary gland extract (SGE), respectively. Spirochete
loads in murine tissues were evaluated using real-time q-PCR. SGE induced
significantly increased spirochete numbers in the skin on the days 4 and 6
post-infection (p.i.). On the other hand, decreased bacterial load in the heart
of SGE-treated mice was demonstrated in comparison with control animals. The
inoculation of tick saliva increased spirochete load in the urinary bladder on
day 6 p.i., while the number of spirochetes in the heart declined on day 6 p.i.
The feeding of I. ricinus nymphs raised the spirochete load in the bladder on
the days 4 and 6 p.i. On day 6, the number of spirochetes found in the heart was
significantly lower than in controls. The prevalence of spirochetes in ticks
infected by feeding on mice was more than 10 times higher when the mice were
infected with the mixture of spirochetes and saliva or SGE, in comparison with
spirochetes alone. The presence of SGE in the infectious inoculum increased the
spirochete burden per tick from 0 to almost 28,000. Taken together, these
results show a very early effect of tick saliva on the proliferation and
distribution of Borrelia spirochetes in the host, probably due to the effect of
saliva on the host innate immunity mechanisms.

PMID: 19147403 [PubMed - as supplied by publisher]
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ViestiKirjoittaja soijuv » Pe Tammi 23, 2009 21:30

Borreliabakteerin on lukuisten tutkimusten mukaan osoitettu olevan erittäin selviytymiskykyisen bakteerin. Seuraavan tutkimuksen mukaan borreliabakteeri muuntaa geenejään ja proteiinejaan silloin kun se joutuu alttiiksi korkeille hiilidioksidipitoisuuksille. Aiemmin sen todettu toimivan samoin muissakin ääriolosuhteissa kuten suurissa lämpötilan- ja/tai Ph:n vaihteluissa.

http://www.ncbi.nlm.nih.gov/entrez/quer ... &DB=pubmed


J Bacteriol. 2006 Nov 10; [Epub ahead of print]

Borrelia burgdorferi alters its gene expression and antigenic profile in response to CO2 levels.

* Hyde JA,
* Trzeciakowski JP,
* Skare JT.

Department of Microbial and Molecular Pathogenesis, and Department of Systems Biology and Translational Medicine, Texas A&M University Health Science Center, College Station, Texas 77843-1114.

The etiologic agent of Lyme disease, Borrelia burgdorferi, must adapt to the distinct environments of the arthropod vector and mammalian host during its complex lifecycle. B. burgdorferi alters gene expression and protein synthesis in response to temperature, pH and other uncharacterized environmental factors. The hypothesis tested in this study is that dissolved gases, including CO2, serve as a signal for B. burgdorferi to alter protein production and gene expression. This study focused on the characterization of in vitro anaerobic (5% CO2, 3% H2, 0.087 PPM O2) and microaerophilic (1% CO2, 3.48 PPM O2) growth conditions and how they modulate protein synthesis and gene expression in B. burgdorferi. Several immunoreactive proteins were synthesized at higher levels under anaerobic conditions, including BosR, NapA, DbpA, OspC, BBK32 and RpoS. Previous studies demonstrated that NapA is produced at lower levels when microaerophilic cultures were purged with nitrogen gas to displace oxygen and CO2.

This study identifies CO2 as a contributing factor to the observed change in NapA synthesis. Specifically, the reduction of dissolved CO2, independent of O2 levels, resulted in reduced NapA synthesis. BosR, DbpA, OspC and RpoS synthesis was also decreased with the displacement of CO2. Quantitative RT-PCR indicated that dbpA, ospC and bbk32 transcripts are increased in the presence of CO2 indicating that these putative borrelial virulence determinants are regulated at the transcriptional level. As such, dissolved CO2 may be an additional cue for borrelial host-adaptation and gene regulation.

PMID: 17098904 [PubMed - as supplied by publisher]
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ViestiKirjoittaja soijuv » Pe Tammi 23, 2009 21:34

Borreliabakteeri kykenee aiheuttamaan eri eläinlajeille infektion. Hiirikokeissa todettiin sellaisten hiirten, joilla oli alhainen Interleukiini 10 (IL-10) selvinneen borreliabakteerista 10 kertaa muita hiiriä paremmin.

http://www.ncbi.nlm.nih.gov/entrez/quer ... &DB=pubmed

J Immunol. 2006 Nov 15;177(10):7076-85.

IL-10 Deficiency Promotes Increased Borrelia burgdorferi Clearance Predominantly through Enhanced Innate Immune Responses.

* Lazarus JJ,
* Meadows MJ,
* Lintner RE,
* Wooten RM.

Department of Medical Microbiology and Immunology, Medical University of Ohio, Toledo, OH 43614.

Borrelia burgdorferi is capable of persistently infecting a variety of hosts despite eliciting potent innate and adaptive immune responses. Preliminary studies indicated that IL-10-deficient (IL-10(-/-)) mice exhibit up to 10-fold greater clearance of B. burgdorferi from target tissues compared with wild-type mice, establishing IL-10 as the only cytokine currently known to have such a significant effect on spirochetal clearance. To further delineate these IL-10-mediated immune effects, kinetic studies indicated that spirochete dissemination to target tissues is similar in both wild-type and IL-10(-/-) mouse strains, and that enhanced clearance of B. burgdorferi in IL-10(-/-) mice is correlated with increased B. burgdorferi-specific Ab as early as 2 wk postinfection. Immunoblot analysis indicated that Abs produced by infected IL-10(-/-) and wild-type mice recognize similar ranges of spirochetal Ags. Immune sera from IL-10(-/-) and wild-type mice also exhibited similar bactericidal activity in vitro, and passive transfer of these immune sera into B. burgdorferi-infected SCID mice caused similar reductions of bacterial numbers in target tissues. Infectious dose studies indicated that 8-fold more B. burgdorferi were needed to efficiently infect naive IL-10(-/-) mice, suggesting these animals possess higher innate barriers to infection. Moreover, macrophages derived from IL-10(-/-) mice exhibit enhanced proinflammatory responses to B. burgdorferi stimulation compared with wild-type controls, and these responses are not significantly affected by the presence of immune serum. These findings confirm that B. burgdorferi clearance by innate immune responses is more efficient in the absence of IL-10, and these activities are not directly related to increased levels of B. burgdorferi-specific Ab.

PMID: 17082624 [PubMed - in process]
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ViestiKirjoittaja soijuv » La Tammi 24, 2009 21:41

Elimistö puolustaa itseään borreliabakteeria vastaan aiheuttamalla solukuoleman ja tulehdustilan.


Infect Immun. 2008 Jan;76(1):56-70.

Phagocytosis of Borrelia burgdorferi, the Lyme disease spirochete, potentiates innate immune activation and induces apoptosis in human monocytes.

Cruz AR, Moore MW, La Vake CJ, Eggers CH, Salazar JC, Radolf JD.

Department of Medicine, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT 06030-3715, USA.

We have previously demonstrated that phagocytosed Borrelia burgdorferi induces activation programs in human peripheral blood mononuclear cells that differ qualitatively and quantitatively from those evoked by equivalent lipoprotein-rich lysates. Here we report that ingested B. burgdorferi induces significantly greater transcription of proinflammatory cytokine genes than do lysates and that live B. burgdorferi, but not B. burgdorferi lysate, is avidly internalized by monocytes, where the bacteria are completely degraded within phagolysosomes. In the course of these experiments, we discovered that live B. burgdorferi also induced a dose-dependent decrease in monocytes but not a decrease in dendritic cells or T cells and that the monocyte population displayed morphological and biochemical hallmarks of apoptosis. Particularly noteworthy was the finding that apoptotic changes occurred predominantly in monocytes that had internalized spirochetes. Abrogation of phagocytosis with cytochalasin D prevented the death response. Heat-killed B. burgdorferi, which was internalized as well as live organisms, induced a similar degree of apoptosis of monocytes but markedly less cytokine production. Surprisingly, opsonophagocytosis of Treponema pallidum did not elicit a discernible cell death response. Our combined results demonstrate that B. burgdorferi confined to phagolysosomes is a potent inducer of cytosolic signals that result in (i) production of NF-kappaB-dependent cytokines, (ii) assembly of the inflammasome and activation of caspase-1, and (iii) induction of programmed cell death.

We propose that inflammation and apoptosis represent mutually reinforcing components of the immunologic arsenal that the host mobilizes to defend itself against infection with Lyme disease spirochetes.

PMID: 17938216 [PubMed - indexed for MEDLINE]
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ViestiKirjoittaja soijuv » La Tammi 24, 2009 21:50

Borreliabakteerin eri alalajit etenevät ihossa eri lailla. Amerikassa
tavallinen B. burgdorferi etenee nopeammin ja aiheuttaa enemmän
oireita kuin Itävallassa tyypillisesti esiintyvä B. afzelii.



Clin Infect Dis. 2008 Jan 1;46(1):85-92.

Higher mRNA levels of chemokines and cytokines associated with
macrophage activation in erythema migrans skin lesions in patients from
the United States than in patients from Austria with Lyme borreliosis.

Jones KL, Muellegger RR, Means TK, Lee M, Glickstein LJ, Damle N, Sikand
VK, Luster AD, Steere AC.

Division of Rheumatology, Allergy, and Immunology, Center for Immunology
and Inflammatory Diseases, Harvard Medical School, Massachusetts General
Hospital, Boston, Massachusetts 02114, USA. kljones@partners.org

BACKGROUND: Erythema migrans (EM) is caused primarily by Borrelia
afzelii in Europe and solely by Borrelia burgdorferi in the United
States. B. burgdorferi infection in the United States has previously
been associated with faster expansion of EM lesions and with more
associated symptoms, compared with B. afzelii infection in Europe.
However, reasons for these differences are not yet known.

METHODS: We determined the Borrelia species infecting 67 US or Austrian
patients with EM. The clinical pictures and chemokine and cytokine mRNA
levels in lesional skin were then compared in the 19 B.
burgdorferi-infected US patients and the 37 B. afzelii-infected Austrian
patients, the 2 largest groups.

RESULTS: The 19 B. burgdorferi-infected US patients had faster-expanding
EM lesions and a median of 4 associated signs and symptoms, whereas the
37 B. afzelii-infected Austrian patients had slower-expanding lesions
and usually did not experience associated symptoms. Compared with the EM
lesions of B. afzelii-infected Austrian patients, those of B.
burgdorferi-infected US patients had significantly higher mRNA levels of
chemokines associated with activation of macrophages, including
chemoattractants for neutrophils (CXCL1), macrophages (CCL3 and CCL4),
and T helper 1 cells (CXCL9, CXCL10, and CXCL11). In addition, compared
with the EM lesions of Austrian patients, the EM lesions of US patients
tended to have higher mRNA levels of the macrophage-associated
proinflammatory cytokines interleukin 1beta and tumor necrosis factor
alpha, and they had significantly higher mRNA expression of the
antiinflammatory cytokines interleukin 10 and transforming growth factor
beta.

CONCLUSIONS: The EM lesions of B. burgdorferi-infected US patients
expanded faster, were associated with more symptoms, and had higher mRNA
levels of macrophage-associated chemokines and cytokines than did the EM
lesions of B. afzelii-infected Austrian patients.

Publication Types:
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.
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ViestiKirjoittaja soijuv » Su Tammi 25, 2009 12:03

Tutkimuksen mukaan Bb kykenee liikkumaan nopeasti. Siinä saattaa olla yksi selittävä syy sille miksi puolustusjärjestelmän solut eivät kykene tuhoamaan borreliabakteeria tehokkaasti.


PLoS ONE. 2008 Feb 20;3(2):e1633.
Clocking the lyme spirochete.
Malawista SE, de Boisfleury Chevance A.
Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America.

In order to clear the body of infecting spirochetes, phagocytic cells must be able to get hold of them. In real-time phase-contrast videomicroscopy we were able to measure the speed of Borrelia burgdorferi (Bb), the Lyme spirochete, moving back and forth across a platelet to which it was tethered. Its mean crossing speed was 1,636 microm/min (N = 28 ), maximum, 2800 microm/min (N = 3). This is the fastest speed recorded for a spirochete, and upward of two orders of magnitude above the speed of a human neutrophil, the fastest cell in the body. This alacrity and its interpretation, in an organism with bidirectional motor capacity, may well contribute to difficulties in spirochete clearance by the host.

PMID: 18286190
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ViestiKirjoittaja soijuv » Su Tammi 25, 2009 18:10

Borreliabakteeri aiheuttaa sekä glia- että hermosolujen kuolemaa aivokudoksissa. Havainto tehtiin ex vivo -tutkimuksessa jossa apinoiden aivokudoksesta otettuihin näytteisiin laitettiin eläviä spirokeettoja.


Am J Pathol. 2008 Nov;173(5):1415-27. Epub 2008 Oct 2.

Interaction of the Lyme Disease Spirochete Borrelia burgdorferi with Brain Parenchyma Elicits Inflammatory Mediators from Glial Cells as Well as Glial and Neuronal Apoptosis.


Ramesh G, Borda JT, Dufour J, Kaushal D, Ramamoorthy R, Lackner AA, Philipp MT.

Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University, 18703 Three Rivers Rd., Covington, LA 70433. philipp@tulane.edu.

Lyme neuroborreliosis, caused by the spirochete Borrelia burgdorferi, often manifests by causing neurocognitive deficits. As a possible mechanism for Lyme neuroborreliosis, we hypothesized that B. burgdorferi induces the production of inflammatory mediators in the central nervous system with concomitant neuronal and/or glial apoptosis. To test our hypothesis, we constructed an ex vivo model that consisted of freshly collected slices from brain cortex of a rhesus macaque and allowed live B. burgdorferi to penetrate the tissue. Numerous transcripts of genes that regulate inflammation as well as oligodendrocyte and neuronal apoptosis were significantly altered as assessed by DNA microarray analysis. Transcription level increases of 7.43-fold (P = 0.005) for the cytokine tumor necrosis factor-alpha and 2.31-fold (P = 0.016) for the chemokine interleukin (IL)-8 were also detected by real-time-polymerase chain reaction array analysis. The immune mediators IL-6, IL-8, IL-1beta, COX-2, and CXCL13 were visualized in glial cells in situ by immunofluorescence staining and confocal microscopy. Concomitantly, significant proportions of both oligodendrocytes and neurons undergoing apoptosis were present in spirochete-stimulated tissues. IL-6 production by astrocytes in addition to oligodendrocyte apoptosis were also detected, albeit at lower levels, in rhesus macaques that had received in vivo intraparenchymal stereotaxic inoculations of live B. burgdorferi. These results provide proof of concept for our hypothesis that B. burgdorferi produces inflammatory mediators in the central nervous system, accompanied by glial and neuronal apoptosis.

PMID: 18832582 [PubMed - in process]

PMCID: PMC2570132 [Available on 05/01/09]
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ViestiKirjoittaja soijuv » Ti Helmi 10, 2009 20:24

Borreliabakteeri on yksi harvoista mikrobeista joka ei tarvitse rautaa kasvuunsa. Tutkijoiden mukaan näyttää kuitenkin siltä että se tarvitsee manganeesia. Jatkossa selvitetään mikä sen osuus on bakteerin muuttumisessa virulentiksi.


Disease
Scientists Identify Potential Key to Lyme Disease
By
Feb 9, 2009 - 5:39:27 PM

(HealthNewsDigest.com) - DALLAS - Researchers at UT Southwestern Medical Center have identified a protein that may help give Lyme disease its bite.

The findings suggest that the bacterial protein, which aids in transporting the metal manganese, is essential for the bacterium that causes Lyme disease to become virulent.


"We believe our findings provide a foundation for further defining metal homeostasis in this human pathogen and may lead to new strategies for thwarting Lyme disease," said Dr. Michael Norgard, chairman of microbiology at UT Southwestern and senior author of a study now online and in an upcoming issue of the Proceedings of the National Academy of Sciences.

Lyme disease, discovered in 1977, is the most prevalent tick-borne infection in the U.S. Borrelia burgdorfei, the bacterium that causes Lyme disease, lives in infected mammals and in the midgut of ticks. When an infected tick bites an animal or a human, the bacteria are transmitted to the new host. Infection causes fever, malaise, fatigue, headache, muscle and joint aches, and a characteristic "bull's-eye" rash that surrounds the site of infection.

To establish infection, however, the bacterium also must acquire a number of essential nutrients, including metals like manganese from its mammalian and tick hosts. Until now, no metal transporter responsible for this acquisition had been identified in this bacterium.

In the current study, microbiologists examined whether bacteria genetically engineered to lack this manganese transporter, called BmtA, transmitted Lyme disease to ticks and mice. The bacterium lacking the transporter, Dr. Norgard said, grows a bit more slowly in the test tube but is not dramatically different from the normal version.

"When you try to grow it in a mouse, however, it can't grow," he said. "The fact that the bacterium without this particular manganese transporter can't grow in a mouse raises important questions about what aspects of physiology and metabolism contribute to the pathogenicity of the organism."

Lead author Dr. Zhiming Ouyang, postdoctoral researcher in microbiology at UT Southwestern, said another newly discovered characteristic about the bacterium that causes Lyme disease is that it doesn't seem to require iron to function, something most other pathogens need to survive.

"Out of the thousands of bacteria known, the Lyme disease agent and only one or two other bacterial species do not require iron for growth," Dr. Ouyang said. "That raises the question as to what other metal co-factors the Lyme disease bacterium depends on to carry out the work that iron does for all these other biological systems. Our research suggests that manganese is a really important one."

The next step is to understand the exact mechanism of how manganese functions in the organism.

"I really think that there's also something to the notion that manganese may regulate the expression of other virulence factors," Dr. Norgard said. "It could be that manganese has more of an indirect effect, but more research is needed to determine what must happen for Borrelia burgdorfei to become virulent."

Researchers from Indiana University School of Medicine collaborated on the study.

The research was funded by the National Institute of Allergy and Infectious Diseases.

www.HealthNewsDigest.com

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ViestiKirjoittaja soijuv » Ti Helmi 24, 2009 21:16

Bb:n flagelloja nähdään elektroni kryotomografialla. Flagelloja on 7-11.


Sunday, February 22, 2009
http://spirochetesunwound.blogspot.com/ ... relia.html

Viewing the arrangement of Borrelia burgdorferi flagella by electron cryotomography
The most peculiar feature of spirochetes may be the location of their flagella, the thin motility structures that propel bacteria through liquids. Flagella typically extend out from the surface of bacteria into the surroundings. Spirochetes, being not so typical, keep their flagella hidden in the periplasm between the cytoplasmic and outer membranes (see figure). For example, the Lyme disease spirochete Borrelia burgdorferi has 7-11 flagella attached near each end of the "protoplasmic" or cell cylinder, with each flagellum extending through the periplasm towards the center of the spirochete. The flagella impose a flat-wave shape (not a spiral shape!) on B. burgdorferi by wrapping around its protoplasmic cylinder.

from Rosa et al., 2005

How do flagella that are located in the periplasm drive the spirochete through the medium? B. burgdorferi motility is thought to require the rotation of its flagella against the cell cylinder, causing the cell body to gyrate.

B. burgdorferi flagella often appear as a bundle when observed by standard transmission electron microscopy. Here is one such image from a 2000 study revealing at least 10 flagella in a cross section of B. burgdorferi. With the flagella arranged in this manner, it is difficult to imagine how the flagella that are not in direct contact with the cell cylinder could contribute to its gyration.

A study by Charon and colleagues in the January 2009 issue of Journal of Bacteriology suggests that the flagellar bundle is an artifact of the standard techniques used to prepare the samples for electron microscopy. They employed the emerging technique of electron cryotomography to avoid the fixation and staining procedures that often introduce artifacts into samples. Electron cryotomography consists of the following steps:

To preserve structure, the specimen is plunge frozen at -165°C or less. Fixing or staining is not necessary.
While maintaining the sample at the ultralow temperature, 2D projections of the sample are obtained at different angles by transmission electron microscopy.
Computer software assembles the 3D structure of the specimen from the 2D projections.
The software also permits slices of the specimen to be observed without having to actually perform thin sectioning.

Here's a cross-section of B. burgdorferi as viewed by electron cryotomography. Note that the flagella are arranged in a single layer within the periplasm, not in a bundle.

Figure 1 of Charon et al. Bar, 50 nm.
PFs, periplasmic flagella; PS, periplasmic space; PM, plasma (or cytoplasmic) membrane; OM, outer membrane.

A longitudinal slice through the periplasm of B. burgdorferi reveals nine flagella neatly arranged in a parallel fashion along the surface of the protoplasmic cylinder. The authors refer to this array as a "flat ribbon." Each flagellum in the ribbon is separated by ~3 nm, allowing each to rotate in the same direction without interference from neighboring flagella.

Figure 5 of Charon et al. Bar, 200 nm.

3D reconstruction of a section of the spirochete illustrates the flat ribbon of flagella (in red) wrapping around the cell cylinder (in blue). Only a section of the cell cylinder is shown, and the outer membrane has been removed from the image.

These new images support a model for for B. burgdorferi motility that was first described back in the 1990s. In this model, the rotation of the flagella against the cell cylinder generates gyrating waves that progress backwards along the cell body. As explained in the discussion of the Charon et al. paper, it is conceivable that all 7-11 flagella must lie against the cell cylinder as a flat ribbon to exert the force necessary to generate the waves; a flagella bundle may not exert enough force. The torque generated by the rotating flagella causes a counter rotation of the cell cylinder (panel a below). The backward-propagating, gyrating waves push the spirochete through the medium. Flagella arranged in a bundle would not generate enough torque because of potential interference between rotating flagella (panel b).

Figure 8 of Charon et al. a. Flagella arranged in a flat ribbon. b. Flagella arranged in a bundle.

This model also explains why B. burgdorferi moves so well through viscous gel-like material such as the extracellular matrix; the gel provides traction for the backward-progressing waves to drive the spirochete through the medium.

Here's a movie animating B. burgdorferi motility, first presented at a meeting in 2001 .

SOURCE

You can also see real B. burgdorferi gyrating and generating backward-moving waves in a movie embedded in Dr. Nyles Charon's website.

Reference

N. W. Charon, S. F. Goldstein, M. Marko, C. Hsieh, L. L. Gebhardt, M. A. Motaleb, C. W. Wolgemuth, R. J. Limberger, N. Rowe (2009). The Flat-Ribbon Configuration of the Periplasmic Flagella of Borrelia burgdorferi and Its Relationship to Motility and Morphology Journal of Bacteriology, 191 (2), 600-607 DOI: 10.1128/JB.01288-08
Posted by Microbe Fan at 11:01 PM
Labels: Borrelia, Lyme disease, motility
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Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » Ma Maalis 09, 2009 13:56

Spirokeettoja tunnetaan huonosti. Ne kykenevät liikkumaan elimistön eri nesteissä ja kudoksissa nopeasti paikasta toiseen esim. luuytimessä, hampaan plakissa jne.

Understanding spirochetes Feedback

UB oral biologist Chunhao (Chris) Li has spent his career studying spirochetes, a family of bacteria whose species cause a variety of human diseases. Photo: DOUGLAS LEVERE
By JUDSON MEAD
Published: February 25, 2009
When Chunhao (Chris) Li joined the faculty in the Department of Oral Biology, School of Dental Medicine, in 2005, he put UB on the map of research hotspots in the effort to better understand spirochetes, a family of bacteria whose different species cause a variety of human diseases, including syphilis and Lyme disease.

More than 60 species of spirochetes have been identified among human oral flora and one, Treponema denticola, is strongly associated with periodontal disease.

Spirochetes have highly specialized features that play roles in their virulence. The coil-shaped microbes can move rapidly, practically sprinting compared with their less-mobile bacterial cousins; more remarkably, they travel easily through viscous media, such as cartilage or dental plaque, that other bacteria can?t transit; and they can adapt to radically different host environments in one lifetime. And for such medically important bacteria, spirochetes are poorly understood.


Before coming to UB, Li spent seven years at the University of West Virginia as a postdoctoral researcher and then a faculty member working with Nyles Charon, one of the world?s leading experts on spirochetes.

Now he directs his own lab on the third floor of Foster Hall, South Campus. This summer, Li?s lab was awarded three grants totaling more than $2 million from the National Institute of Dental and Craniofacial Research and the National Institute of Allergy and Infectious Diseases, and a smaller grant from the American Heart Association to pursue research on three fronts.

Li is studying the ability to move in particular directions (motility) and the ability to select destination (chemotaxis) of the Lyme disease-causing spirochete Borrelia burgdorferi, and the roles of both motility and chemotaxis in the disease it causes. He also is looking at how Borrelia burgdorferi regulates its host-adaptation, thriving in both ticks and humans. And he is studying the role of a particular toxin produced by Treponema denticola in periodontal disease.

Li?s lab currently employs a single postdoctoral researcher; the research funds will allow him to recruit three more postdocs and a full-time technician.

In earlier research, Li demonstrated that removing a particular gene interferes with Borrelia burgdorferi?s motility. Spirochetes are shaped like long coils and travel with a wave-like motion. Reversing course requires the coordination of their flagella from each end. The gene Li removed coded a protein that is essential for that coordination. Li showed in a mouse model that interfering with the spirochete?s motility in this way prevented it from causing disease. This suggests an avenue for attack on the spirochete.

A second potentially exploitable vulnerability is the internal signaling that allows Borrelia burgdorferi to switch genes on and off to adapt to the host environments of mammal and tick, with their different temperatures and immune responses. Li has described a two-stage signal sequence. If the sequence could be interrupted, the spirochete?s ability to infect humans through ticks would presumably be stopped.

The lab?s work on Treponema denticola currently is focused on a toxin it secretes that appears to cut up human immunoglobulin. Treponema denticola is particularly interesting in dental medicine because it is always found at the frontier in dental plaque, suggesting that it plays a role in periodontal infection. Li hopes to discover whether this protein is a virulence factor.

Although it is only now, using 21st-century tools, that researchers are discovering how it may cause disease, Treponema denticola was one of the first bacteria ever described, in 1683 by Antonio van Leeuwenhoek, who is known as the Father of Microbiology.

One of Li?s recent research successes is the development of a reliable method for producing genetic mutants of Treponema denticola in large enough quantity to study.

Li started research on spirochetes after graduating from medical school in China and working in a hospital for two years. He was interested in infectious diseases and went to graduate school for more study; his mentor and Ph.D. director was an expert on spirochetes, and that set Li on a career path that led through West Virginia to Buffalo.

As it happens, Nyles Charon, Li?s mentor at West Virginia, whom he credits with his success as an independent researcher, has a daughter in medical school at UB, so he visits Buffalo occasionally, much to Li?s delight.
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Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » Ke Maalis 11, 2009 18:47

Appl Environ Microbiol. 2009 Feb 27; [Epub ahead of print]

Climate and tick seasonality predict Borrelia burgdorferi genotype distribution.

Gatewood AG, Liebman KA, Vourc'h G, Bunikis J, Hamer SA, Cortinas R, Melton F,Cislo P, Kitron U, Tsao J, Barbour AG, Fish D, Diuk-Wasser MA. Department of Epidemiology and Public Health, Yale School of Medicine, 60College Street, New Haven, Connecticut 06520; National Institute forAgricultural Research, UR346 Animal Epidemiology, F-63122 Saint GenesChampanelle, France; Department of Microbiology and Molecular Genetics,University of California, Irvine, 3046 Hewitt Hall, Irvine, California 92697;Department of Fisheries and Wildlife, Michigan State University, 13 NaturalResources Building East Lansing, Michigan 48824; Department of Entomology,University of Nebraska, Lincoln, 12BA Entomology Hall, East Campus, Lincoln,Nebraska 68583; Division of Science & Environmental Policy, California StateUniversity Monterey Bay, 100 Campus Center, Seaside, California 93955; NASA AmesResearch Center, Moffett Field, California 94035; Department of EnvironmentalStudies, Emory University, 400 Dowman Drive, Atlanta, Georgia 30322; Departmentof Large Animal Clinical Sciences, Michigan State University, East Lansing,Michigan 48824.

The blacklegged tick, Ixodes scapularis, is of significant public healthimportance as a vector of Borrelia burgdorferi, the agent of Lyme borreliosis.The timing of seasonal activity of each immature I. scapularis life stagerelative to the next is critical for the maintenance of B. burgdorferi becauselarvae must feed after an infected nymph to efficiently acquire the infectionfrom reservoir hosts. Recent studies have shown that some strains of B.burgdorferi do not persist in the primary reservoir host for more than a fewweeks, thereby shortening the window of opportunity between nymphal and larvalfeeding that sustains their enzootic maintenance. We tested the hypothesis thatclimate is predictive of geographic variation in the seasonal activity of I.scapularis, which in turn differentially influences the distribution of B.burgdorferi genotypes within the geographic range of I. scapularis. We analyzedthe relationships between climate, seasonal activity of I. scapularis, and B.burgdorferi genotype frequency in 30 geographically diverse sites in thenortheastern and Midwestern US. We found that the magnitude of the differencebetween summer and winter daily temperature maximums was positively correlatedwith the degree of seasonal synchrony of the two immature stages of I.scapularis. Genotyping revealed an enrichment of 16S-23S rRNA intergenic spacerrestriction fragment length polymorphism sequence type 1 strains relative toothers at sites with lower seasonal synchrony. We conclude thatclimate-associated variability in the timing of I. scapularis host-seekingcontributes to geographic heterogeneities in the frequencies of B. burgdorferigenotypes, with potential consequences for Lyme borreliosis morbidity.

PMID: 19251900 [PubMed - as supplied by publisher]
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Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » Ke Syys 02, 2009 11:33

Tri Gilbert (Montanan yliopisto 2009) alkaa opiskelijoidensa kanssa tutkia geenejä jotka mahdollistavat borreliabakteerin siirtymisen punkista ihmiseen/eläimeen. Tieto saattaa auttaa tehokkaampien hoitojen kehittämisessä. Tehtävä on vaikea sillä borreliabakteerilla on lineaarinen kromosomisto ja 22 plasmidia (DNA molekyylejä jotka ovat erillään solujen kromosomeista). Borreliabakteerilla on useita tauteja aiheuttavia kantoja ja niissä plasmidit ja geenit ovat eri paikoissa.


Bacterial Plasmids and Lyme Disease - University of Montana Western Research

Tuesday, September 01, 2009
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Bacterial Plasmids and Lyme Disease
Aug 31st, 2009 | By l_henneman | Category: current projects

Borrelia burgdorferi is the bacteria species carried by ticks that is responsible for Lyme disease. Dr. Michael Gilbert and his students want to know which genes are involved in the transmission of B. burgdorferi from the tick vector to the mammalian host, because finding this out could eventually lead to more successful treatments for Lyme disease.

This goal is complicated by the unique genomic structure of B. burgdorferi. Unlike most other bacteria, B. burgdorferi has a linear chromosome and 22 linear and circular plasmids (DNA molecules that are separate from the cell?s chromosome) which is the largest plasmid contingent known among bacteria. It is known that genes essential to the infection process are located on these plasmids, but the plasmid DNA is so different from that of other bacteria that the functions of individual genes could not be deduced simply by comparison with other species, as is often done.

To solve the problem, Gilbert developed an inducible promoter system, which allows him to turn on specific bacterial genes after injecting them into mice, in order to see how they affect the infection process. Another problem, though, is that while he has been successful in using this technique to artificially control genes in one strain of B. burgdorferi (B31-A3), there are multiple strains that cause disease and these strains differ in which plasmids are present and which genes are on which plasmids.

Gilbert just received a five-year grant of over $500,000 from the National Institutes of Health NIH through the Montana IdEA Network Biomedical Research Excellence (INBRE) program to refine the inducible promoter system for use another strain of B. burgdorferi (297-AH130). The goal is to continue to add on additional strains until a more complete picture of the overall mechanism for Lyme disease infection emerges.

Gilbert currently has one student working on this project in his lab, with another starting in the fall of 2009. He will continue to hire student researchers as the project progresses.
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Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » Ma Syys 21, 2009 10:21

Borreliabakteerin genotyypeistä RST1 esiintyi yleisimmin sellaisilla henkilöillä joilla oli kroonisia niveltulehduksia. (2009)

Arthritis Rheum. 2009 Jun 29;60(7):2174-2182 [Epub ahead of print] Analysis of Borrelia burgdorferi genotypes in patients with lyme arthritis: Highfrequency of ribosomal RNA intergenic spacer type 1 strains inantibiotic-refractory arthritis.

Jones KL, McHugh GA, Glickstein LJ, Steere AC. Harvard Medical School and Massachusetts General Hospital, Boston,Massachusetts.

OBJECTIVE: Most of the Borrelia burgdorferi genotypes have been isolated fromerythema migrans (EM) skin lesions in patients with Lyme disease. OspC type Kstrains, which are 16S-23S ribosomal RNA intergenic spacer type 2 (RST2)strains, are most commonly recovered, but a higher percentage of OspC type Astrains (RST1), the next most commonly recovered type, is detectable in blood.The goal of this study was to determine the B burgdorferi genotypes in thejoints of patients with Lyme arthritis. METHODS: Joint fluid samples from 124patients seen over a 30-year period were analyzed for OspC types by semi-nestedpolymerase chain reaction (PCR) and sequencing, and for RSTs by nested PCR andrestriction fragment length polymorphism analysis. These results were correlatedwith clinical outcome. RESULTS: OspC and RST genotypes were identified in 49 ofthe 124 joint fluid samples (40%). In these 49 samples, OspC type K strains(RST2) were identified in 21 samples (43%), OspC type A strains (RST1) wereidentified in 11 samples (22%), and 8 other OspC types and all 3 RSTs wereidentified among the remaining 17 samples (35%). However, among the 17 patientswho had been treated with antibiotics according to current guidelines, all 7patients who were infected with RST1 strains had antibiotic-refractoryarthritis, compared with 4 of 6 patients infected with RST2 strains and only 1of 4 infected with RST3 strains (P = 0.03).

CONCLUSION: Most of the B burgdorferi genotypes, particularly OspC type K (RST2), were identified in the joint fluid of patients with Lyme arthritis, and the genotype frequencies found in joints reflected those in EM skin lesions. However, RST1 strains were most frequent in patients with antibiotic-refractory arthritis. Our results help to further the understanding of the differential pathogenicity of strains of B burgdorferi. PMID: 19565522 [PubMed - as supplied by publisher]
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Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » To Loka 08, 2009 09:25

Borrelioosin neurologiset oireet johtuvat borreliabakteerin pääsystä veri-aivoesteen läpi keskushermostoon. Tällä hetkellä ei kuitenkaan tiedetä mitä mekanismeja bakteeri käyttää. (Slovakia 2009)
FEMS Immunol Med Microbiol. 2009 Aug 6; [Epub ahead of print]

Pathogen translocation across the blood-brain barrier.

Pulzova L, Bhide MR, Andrej K. Laboratory of Biomedical Microbiology and Immunology, Department of Microbiology and Immunology, University of Veterinary Medicine, Kosice, Slovakia. Abstract

Neurological manifestations caused by neuroinvading pathogens aretypically attributed to penetration of the blood-brain barrier (BBB) andinvasion of the central nervous system. However, the mechanisms used by manypathogens (such as Borrelia) to traverse the BBB are still unclear. Recentstudies revealed that microbial translocation across the BBB must involve arepertoire of microbial-host interactions (receptor-ligand interactions). However, the array of interacting molecules responsible for the borrelialtranslocation is not yet clearly known. Pathogens bind several host molecules(plasminogen, glycosaminoglycans, factor H, etc.) that might mediate endothelial interactions in vivo. This review summarizes our current understanding of the pathogenic mechanisms involved in the translocation of the BBB by neuroinvasive pathogens. http://eutils.ncbi.nlm.nih.gov/entrez/e ... rlinksPMID: 19732140 [PubMed - as supplied by publisher]
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Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » To Marras 19, 2009 10:57

"Borreliabakteerin spirokeettamuodot ovat viljelyalustalla erittäin liikkuvia. Yleinen käsitys on ollut, että bakteerit siirtyvät punkin suolistosta nopeasti eteenpäin punkin sylkirauhasiin ja siitä eteenpäin esim. ihmiseen. Näin ei kuitenkaan ole. Punkin aterioidessa, bakteerit ovat lähes liikkumattomia sillä punkin suolistossa olevat molekyylit estävät niiden liikkumisen. Sen sijaan bakteerit jakautuvat ja ympäröivät suoliston tai epiteelin solut muodostaen kiinteitä verkostoja. Vasta kun ne ovat täydellisesti ympäröineet epiteelisolut, ne tulevat liikkuviksi ja kykenenvät läpäisemään punkin suoliston. Vain pieni osa bakteereista pääsee läpi punkin sylkirauhasiin. Bakteerien siirtyminen punkin suolistosta ihmiseen tai muihin eläimiin tapahtuu siis kahdessa vaiheessa eikä yhdessä kuten aiemmin on uskottu."

http://www.sciencedaily.com/releases/20 ... 180134.htm

How Ticks Transmit Lyme Disease to Humans: Imaging Technique Leads to Better Understanding

ScienceDaily (Nov. 17, 2009) ? Using a powerful microscopic live imaging technique, a research team led by Dr. Justin Radolf, professor in the Departments of Medicine and Genetics and Developmental Biology at the University of Connecticut Health Center, has discovered the way ticks transmit Lyme disease to humans is different than previously thought. The research is published online in the Journal of Clinical Investigation.

Lyme disease is caused by transmission of the spirochete bacterium Borrelia burgdorferi from ticks to humans but for a number of technical reasons, the transmission process has been difficult to study.

Radolf and researchers Star Dunham-Ems and Melissa Caimano tried a novel approach. They genetically modified a virulent strain of B. burgdorferi to express green fluorescent protein (GFP). "This bacterium glows and can be followed in the living state as it migrates through the tick to the mouse during feeding," explains Radolf. "Then using a powerful microscopic technique called confocal microscopy, we discovered that the transmission process unfolds quite differently than previously believed."

Spirochetes in culture are highly motile, and it is widely believed that during feeding, the spirochetes in the midgut rapidly move through the wall of the midgut. But Radolf and his team found that during much of the feeding period, the spirochetes do not move. They actually divide and surround the cells of the midgut lining or epithelium, forming tight networks. "We also found that the reason they don't move is that the tick midgut secretes molecules that actually inhibit the motility of the spirochetes," explains Radolf.


Eventually, spirochetes in the networks reach the base of the epithelium by completely surrounding the epithelial cells. At this point, they become motile, detach, and completely penetrate the midgut, although in very small numbers. These few bacteria then swim to the salivary glands, which they penetrate en route to the mouse. "So rather than being entirely motility-driven, dissemination of spirochetes within ticks actually happens in two phases," says Radolf, "which is something we didn't know before."

Lyme disease is the most prevalent vector-borne infection in the United States with more than 25,000 new cases reported annually. A substantial percentage of these cases occur in Connecticut. "The improved understanding of the transmission process revealed by our study could lead to novel strategies for controlling the spread of Lyme disease," says Radolf
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Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » Pe Marras 27, 2009 08:12

Borreliabakteeri elää erilaisissa hyönteisissä ja hämähäkkieläimissä kuten punkeissa sekä eläimissä ja ihmisissä. Bakteeri selviää erilaisissa ympäristöissä esim. Ph:n ja lämpötilan muutoksista muuntamalla pintaproteiinejaan.

http://www.plospathogens.org/article/in ... at.1000676


Author Summary

Lyme disease, caused by the spirochete Borrelia burgdorferi, is the most prevalent arthropod-borne disease in North America. In nature, the bacterium oscillates between its tick vector host (Ixodes spp.) and small rodents (Peromyscus spp.). B. burgdorferi is able to persist in these two very different host environments by modulating the expression of surface lipoproteins proteins, or other proteins, in response to host factors or environmental cues such as temperature and pH. Our interest in this process led to the identification of a homolog of the E. coli ATP-dependent lon protease (lon-1) in B. burgdorferi that was upregulated in response to blood. The prototypical Lon of E. coli is a conserved protease important for the destruction of abnormal and short-lived proteins. B. burgdorferi is unusual in that it also codes for a second lon homolog, lon-2, that was not upregulated in response to blood. In this study, we sought to clarify the roles for Lon-1 and Lon-2 in B. burgdorferi. We present evidence that Lon-1 is an ATP- and Mg2+-dependent protease but does not function in a manner consistent with a prototypical Lon. Lon-2, however, functionally complemented Lon in E. coli. Thus, Lon-1 and Lon-2 appear to have distinct roles in B. burgdorferi; Lon-1 by virtue of its blood induction may be important in host adaptation, while Lon-2 is the functional homolog of E. coli Lon.
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Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » Pe Joulu 11, 2009 21:19

Punkkien välityksellä leviävää toisintokuumetta aiheuttavaa Borrelia hermsii -bakteeria esiintyy aiempaa luultua useammissa eläimissä. Tutkijat löysivät kuolleen pöllön jossa oli em. bakteeria. Bakteeria on myös mm. oravissa. (USA 2009)

http://www.bada-uk.org/wordpress/?p=677

CDC - Identical Strains of Borrelia hermsii in Mammal and Bird
Filed under: Abroad, Animal Management:, Health Care Management:, Publicity & Public Awareness:, Wildlife ? Craig @ 4:44 pm

Volume 15, Number 12?December 2009

Letter

Robert J. Fischer, Tammi L. Johnson, Sandra J. Raffel, and Tom G. Schwan
Author affiliations: National Institutes of Health, Hamilton, Montana, USA (R.J. Fischer, T.L. Johnson, S.J. Raffel, T.G. Schwan); and The University of Montana, Missoula, Montana, USA (T.L. Johnson)

To the Editor: On August 5, 1994, a northern spotted owl, Strix occidentalis caurina, was found dead in Kittitas County, Washington, USA (1). A thorough investigation and necropsy identified the probable cause of death to be a spirochete infection. The organisms were seen in sections of the bird?s liver with use of modified Steiner silver stain and microscopy. DNA was extracted from the infected liver, and PCR?DNA sequencing of the 16S ribosomal RNA (rRNA) locus identified the bacterium as a relapsing fever spirochete related most closely to Borrelia hermsii (1). The lack of additional data surrounding this case precluded Thomas et al. from concluding that this spirochete infecting the owl was B. hermsii. Yet, in a subsequent analysis using the intergenic spacer region, the owl spirochete was included with isolates of B. hermsii (2).

To investigate the distribution and prevalence of B. hermsii , during the summer of 2008, we began a study at Flathead Lake, Lake County, Montana, USA, where 9 persons have contracted relapsing fever since 2002 (3?5). A blood smear from 1 pine squirrel (Tamiasciurus hudsonicus) captured July 9 at Yellow Bay on the east shore of the lake (elevation 887 m; geographic coordinates 47°52´35´´N, 114°01´54´´W) contained spirochetes detected when stained with Giemsa and examined by microscopy (600× brightfield with oil immersion). Whole blood from the squirrel contained live spirochetes visible by dark-field microscopy, and ≈50 μL of this blood was injected intraperitoneally into a laboratory mouse. The next day, a few spirochetes were observed in the peripheral blood of the mouse, and during the next 3 days, the density of spirochetes increased. We used intracardiac puncture to collect blood from the mouse for spirochete isolation in BSK-H medium (Sigma-Aldrich, St Louis, MO, USA) and for analysis by PCR and DNA sequencing of multiple bacterial loci as described elsewhere (4,6).

The spirochetes observed in the squirrel?s blood failed to grow in BSK-H medium after passage in the laboratory mouse; however, we acquired DNA sequences from infected squirrel and mouse blood from PCR amplicons for 6 spirochete loci including 16S rDNA, flaB, gyrB, glpQ, IGS, and vtp. Sequences for the loci were each aligned with homologous sequences from other borrelia in our collection, and each locus grouped the spirochete within the 2 genomic groups of B. hermsii described previously (4,6). The unique squirrel spirochete differed from all other B. hermsii identified in our previous studies; deep branches in each phylogram grouped the spirochete more closely with B. hermsii genomic group I than with genomic group II (data not shown).

Next, we compared the sequences from the squirrel spirochete with those available in the National Center for Biotechnology Information database (www.ncbi.nlm.nih.gov), including those sequences reported for the spirochete found in the spotted owl (AY515269.1, AF116903.1, AF116904.1) (1,2). The 3 trimmed and aligned sequences for the 16S rDNA (1,290 bases), flaB (467 bases), and IGS (665 bases) from the squirrel spirochete were identical to those of the owl spirochete; no base differences were found among the 2,422 bases compared. We also examined DNA extracted from the spotted owl?s liver during the first investigation (1) (provided by Alan G. Barbour). We successfully PCR amplified most of the 16S rDNA and the complete flaB, gyrB, glpQ, and vtp genes from the owl spirochete DNA and determined their sequences. The complete sequences of the first 4 loci from the owl and squirrel spirochetes were identical and differed from all other B. hermsii sequences. A phylogram of the concatenated sequences totaling 5,188 bases demonstrated that the owl and pine squirrel spirochetes were identical and were divergent members of B. hermsii genomic group I (Figure).

Finding the same strain of B. hermsii, separated by ≈525 km, in a pine squirrel and a spotted owl demonstrates a broader geographic distribution and host range for this spirochete than what could have been envisaged previously. The possible role of birds as hosts for the vector Ornithodoros hermsi ticks has been demonstrated elsewhere (4). Given the ecologic overlap of pine squirrels and coniferous forest-dwelling birds, we believe that the previous finding of the infected spotted owl is likely not an isolated event. Instead, it may represent a tick?spirochete cycle for B. hermsii that includes a broader host range for this group of relapsing fever spirochetes than previously appreciated.

Acknowledgments
We thank Jake Beldsoe and Michaela Ponce for their help in the field, Colleen Miller for arranging all travel, Kerry Foresman for advice and equipment, and staff of the University of Montana Flathead Lake Biological Station.

This work was supported by the Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health.

References
1.Thomas NJ, Bunikis J, Barbour AG, Wolcott MJ. Fatal spirochetosis due to a relapsing fever?like Borrelia sp. in a northern spotted owl. J Wildl Dis. 2002;38:187?93.
2.Bunikis J, Tsao J, Garpmo U, Berglund J, Fish D, Barbour AG. Typing of Borrelia relapsing fever group strains. Emerg Infect Dis. 2004;10:1661?4.
3.Schwan TG, Policastro PF, Miller Z, Thompson RL, Damrow T, Keirans JE. Tick-borne relapsing fever caused by Borrelia hermsii, Montana. Emerg Infect Dis. 2003;9:1151?4.
4.Schwan TG, Raffel SJ, Schrumpf ME, Porcella SF. Diversity and distribution of Borrelia hermsii. Emerg Infect Dis. 2007;13:436?42. PubMed DOI
5.Uhlmann EJ, Seed PC, Schwan TG, Storch GA. Polymerase chain reaction of tick-borne relapsing fever caused by Borrelia hermsii. Pediatr Infect Dis J. 2007;26:267?9. PubMed DOI
6.Porcella SF, Raffel SJ, Anderson DE Jr, Gilk SD, Bono JL, Schrumpf ME, et al. Variable tick protein in two genomic groups of the relapsing fever spirochete Borrelia hermsii in western North America. Infect Immun. 2005;73:6647?58. PubMed DOI

Figure
Phylogram based on the alignment of the concatenated DNA sequences containing the 16S rDNA, flaB, gyrB, and glpQ loci for 6 isolates?

Suggested Citation for this Article
Fischer RJ, Johnson TL, Raffel SJ, Schwan TG. Identical strains of Borrelia hermsii in mammal and bird [letter]. Emerg Infect Dis [serial on the Internet]. 2009 Dec [date cited]. Available from http://www.cdc.gov/EID/content/15/12/2064.htm

DOI: 10.3201/eid1512.090792

http://www.cdc.gov/eid/content/15/12/2064.htm
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Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » Ma Tammi 24, 2011 13:19

Borrelia-bakteeri kykenee jo tartunnan alussa säätelemään pintaproteiini C:tä (OspC) ja kykenee siten pakenemaan immuunivastetta. (2010)

Outer Surface Protein C Is a Dissemination-Facilitating Factor of Borrelia burgdorferi during Mammalian Infection

Abstract

Background


The Lyme disease spirochete Borrelia burgdorferi dramatically upregulates outer surface protein C (OspC) in response to fresh bloodmeal during transmission from the tick vector to a mammal, and abundantly produces the antigen during early infection. As OspC is an effective immune target, to evade the immune system B. burgdorferi downregulates the antigen once the anti-OspC humoral response has developed, suggesting an important role for OspC during early infection.

Methodology/Principal Findings

In this study, a borrelial mutant producing an OspC antigen with a 5-amino-acid deletion was generated. The deletion didn't significantly increase the 50% infectious dose or reduce the tissue bacterial burden during infection of the murine host, indicating that the truncated OspC can effectively protect B. burgdorferi against innate elimination. However, the deletion greatly impaired the ability of B. burgdorferi to disseminate to remote tissues after inoculation into mice.

Conclusions/Significance

The study indicates that OspC plays an important role in dissemination of B. burgdorferi during mammalian infection.

Citation: Seemanapalli SV, Xu Q, McShan K, Liang FT (2010) Outer Surface Protein C Is a Dissemination-Facilitating Factor of Borrelia burgdorferi during Mammalian Infection. PLoS ONE 5(12): e15830. doi:10.1371/journal.pone.0015830

Editor: Laurent Rénia, Singapore Immunology Network-A*STAR, Singapore

Received: October 1, 2010; Accepted: November 27, 2010; Published: December 31, 2010

Copyright: ? 2010 Seemanapalli et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Funding: This work was supported in part by AI077733, AR053338, and RR020159 from the National Institutes of Health. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

* E-mail: fliang@vetmed.lsu.edu


Free FULL text available here http://www.plosone.org/article/info%3Ad ... ne.0015830
soijuv
 
Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » Ke Syys 14, 2011 12:46

Useat bakteerit, myös borrelia-bakteerit,keskustelevat keskenään kemiallisten reaktioiden avulla. Princetonin yliopiston tutkija Bonnie Bassler kertoo aiheesta mielenkiintoisella videolla. Bakteerit käyttäytyvät hyvin samalla tavoin kuin ihmiset; taistelevat, tuhoavat, huijaavat, vaihtavat tietoa jne. Bakteerit on tyypillisesti luokiteltu gram - ja + bakteereihin. Basslerin mukaan osalla bakteereista on kuitenkin ammoisista ajoista lähtien ollut kyky tuottaa valoa, ns luxS mekanismi. Borrelia-bakteeri on yksi tällainen bakteeri. Valoa tuottavia bakteereita on sekä gram- että gram+ bakteereissa. Bakteerit alkavat tuottamaan valoa kuitenkin vasta kun tietty määrä bakteereita on yhdessä. Löytö saattaa auttaa esim. uusien antimikrobisten hoitojen kehittelyssä.
http://www.youtube.com/watch?v=SWgfSELnzog&NR=1
soijuv
 
Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

Re: BORRELIA-BAKTEERIN OMINAISUUKSIA

ViestiKirjoittaja soijuv » Ke Maalis 13, 2013 20:21

2013. Borreliabakteerien kyky aiheuttaa ihomuutos vaihtelee bakteerista toiseen. Yleisin ihomuutoksen aiheuttaja on B.afzelii mutta kaikki tämänkään ryhmän bakteerit eivät välttämättä aiheuta ihomuutosta.

Research

Ability to cause erythema migrans differs between Borrelia burgdorferi sensu lato isolates

Ellen Tijsse-Klasen1*, Nenad Pandak2*, Paul Hengeveld1, Katsuhisa Takumi1, Marion PG Koopmans1,3 and Hein Sprong1

Corresponding authors: Ellen Tijsse-Klasen Ellen.TijsseKlasen@gmail.com - Nenad Pandak NPandak@gmail.com

Parasites & Vectors 2013, 6:23 doi:10.1186/1756-3305-6-23

Published: 22 January 2013

http://www.parasitesandvectors.com/cont ... 3/abstract

Background

Lyme borreliosis is a tick-borne disease caused by Borrelia burgdorferi sensu lato. The variety of characteristic and non-specific clinical manifestations is partially explained by its genetic diversity. We investigated the ability of B. burgdorferi sl isolates to cause erythema migrans.

Methods

The genetic constellation of isolates from ticks was compared to isolates found in erythema migrans. PCR and sequence analysis was performed on the plasmid-encoded ospC and the chromosomal 5S-23S rDNA spacer region (IGS).

Results

Seven different B. burgdorferi sl genospecies were identified in 152 borrelia isolates from ticks and erythema migrans biopsies. B afzelii (51%) and B. garinii (27%) were the most common in ticks. From the 44 sequences obtained from erythema migrans samples 42 were B. afzelii, one B. garinii and one B. bavariensis. Significant associations with erythema migrans formation were found for four IGS and two ospC types. Five from forty-five ospC types were associated with more than one genospecies.

Conclusions

B. burgdorferi sl isolates differ in their propensity to cause erythema migrans. These differences were also found within genospecies. In other words, although B. afzelii was mostly associated with erythema migrans, some B. afzelii isolates had a low ability to cause erythema migrans. Our data further support the occurrence of plasmid exchange between borrelia genospecies under natural conditions.
soijuv
 
Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

Re: BORRELIA-BAKTEERIN OMINAISUUKSIA

ViestiKirjoittaja soijuv » Su Touko 19, 2013 09:41

Artikkeli borreliabakteerin selviytymiskeinoista.

Evidence-Based Lyme Disease Practice

Keith Berndtson, MD

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3636972/
soijuv
 
Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

Re: BORRELIA-BAKTEERIN OMINAISUUKSIA

ViestiKirjoittaja soijuv » Su Touko 19, 2013 09:48

(2013) Onko krooninen borrelioosi kroonisen infektion aiheuttama? Kolmenvuosikymmenen tutkimustyön perusteella lopullista vastausta haetaan edelleen. Yhä enenevässä määrin tutkimuksissa on kuitenkin havaittu borreliabakteerin selviävän sekä antibiootihoidoista että immuunipuolustuksesta.

Review of evidence for immune evasion and persistent infection in Lyme disease

Review
(6568) Total Article Views

Authors: Berndtson K
Published Date April 2013 Volume 2013:6 Pages 291 - 306
DOI: http://dx.doi.org/10.2147/IJGM.S44114
Received: 17 February 2013 [These are actual dates the paper was submitted to, accepted for, and published in the journal.<br />These dates are only available for papers published since January 1, 2012]
Accepted: 18 March 2013
Published: 23 April 2013
Keith Berndtson

Park Ridge MultiMed, Park Ridge, IL, USA

Abstract: Is chronic illness in patients with Lyme disease caused by persistent infection? Three decades of basic and clinical research have yet to produce a definitive answer to this question. This review describes known and suspected mechanisms by which spirochetes of the Borrelia genus evade host immune defenses and survive antibiotic challenge. Accumulating evidence indicates that Lyme disease spirochetes are adapted to persist in immune competent hosts, and that they are able to remain infective despite aggressive antibiotic challenge. Advancing understanding of the survival mechanisms of the Lyme disease spirochete carry noteworthy implications for ongoing research and clinical practice.

Keywords: Lyme disease, Borrelia, biofilm, bacterial persistence, antibiotic tolerance
soijuv
 
Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

Re: BORRELIA-BAKTEERIN OMINAISUUKSIA

ViestiKirjoittaja Sailairina » To Maalis 12, 2015 15:39

http://mic.sgmjournals.org/content/161/ ... hort?rss=1

Morphological and biochemical features of Borrelia burgdorferi pleomorphic forms

Leena Meriläinen1, Anni Herranen1, Armin Schwarzbach2 and Leona Gilbert1

Abstract

The spirochaete bacterium Borrelia burgdorferi sensu lato is the causative agent of Lyme disease, the most common tick-borne infection in the northern hemisphere. There is a long-standing debate regarding the role of pleomorphic forms in Lyme disease pathogenesis, while very little is known about the characteristics of these morphological variants. Here, we present a comprehensive analysis of B. burgdorferi pleomorphic formation in different culturing conditions at physiological temperature. Interestingly, human serum induced the bacterium to change its morphology to round bodies (RBs). In addition, biofilm-like colonies in suspension were found to be part of B. burgdorferi’s normal in vitro growth. Further studies provided evidence that spherical RBs had an intact and flexible cell envelope, demonstrating that they are not cell wall deficient, or degenerative as previously implied. However, the RBs displayed lower metabolic activity compared with spirochaetes. Furthermore, our results indicated that the different pleomorphic variants were distinguishable by having unique biochemical signatures. Consequently, pleomorphic B. burgdorferi should be taken into consideration as being clinically relevant and influence the development of novel diagnostics and treatment protocols.


http://www.iltasanomat.fi/terveys/art-1 ... 36915.html

Borrelioosia aiheuttava borreliabakteeri pystyy ehkä piiloutumaan ihmisen immuunipuolustukselta, kertoo tuore tutkimus.

Laboratoriokokeissa havaittiin, että ihmisen seerumi edistää bakteerin muuntautumista pyöreiksi muodoiksi, joissa bakteeri on lepotilassa. Tämä viittaa siihen, että bakteeri saattaa muuttaa muotoaan myös ihmisen elimistössä, mikä edistää sen piiloutumista immuunipuolustukselta.

Borreliabakteerin normaali muoto on spiraalimainen. Olosuhteiden muuttuessa epäedullisiksi se pystyy muuntautumaan pyöreään muotoon, jossa sillä on hyvin vähän aineenvaihduntaa. Pyöreästä muodosta borrelia voi palata myöhemmin takaisin spiraalimaisiksi, aktiivisiksi ja lisääntymiskykyisiksi bakteereiksi.

Borreliaa aiemmin tutkineet tutkijat ovat olleet erimielisiä siitä, mikä on ei-tyypillisten muotojen rooli borrelioosin kehittymisessä ja miten ne liittyvät kroonistuneeseen borrelioosiin. Lisäksi bakteerin eri muotojen ominaisuuksista on tiedetty varsin vähän.

Nyt julkaistussa tutkimuksessa havaittiin, että bakteerin eri muodoilla on erilaiset biokemialliset ominaisuudet. Tästä saattaa olla hyötyä taudin havaitsemisessa.

Tutkimuksen tekivät Jyväskylän yliopiston tutkija Leena Meriläinen yhdessä dosentti Leona Gilbertin johtaman tutkimusryhmän kanssa. Tutkimusartikkeli julkaistiin Microbiology-lehden maaliskuun numerossa kansikuvajuttuna.

Suomessa löydetään vuodessa noin 2 000 borreliatapausta. Esiintyvyys on korkeimmillaan elo- ja marraskuun välillä. Taudin levittäjänä toimivat punkit.

IS, STT
Sailairina
 
Viestit: 684
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Paikkakunta: Kaarina


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