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1.
J Immunol ; 204(2): 386-393, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31818980

RESUMO

The spirochete Borrelia miyamotoi has recently been shown to cause relapsing fever. Like the Lyme disease agent, Borrelia burgdorferi, B. miyamotoi is transmitted through the bite of infected ticks; however, little is known about the response of the immune system upon infection. Dendritic cells (DCs) play a central role in the early immune response against B. burgdorferi We investigated the response of DCs to two different strains of B. miyamotoi using in vitro and ex vivo models and compared this to the response elicited by B. burgdorferi. Our findings show that B. miyamotoi is phagocytosed by monocyte-derived DCs, causing upregulation of activation markers and production of proinflammatory cytokines in a similar manner to B. burgdorferi. Recognition of B. miyamotoi was demonstrated to be partially mediated by TLR2. DCs migrated out of human skin explants upon inoculation of the skin with B. miyamotoi. Finally, we showed that B. miyamotoi-stimulated DCs induced proliferation of naive CD4+ and CD8+ T cells to a larger extent than B. burgdorferi. In conclusion, we show in this study that DCs respond to and mount an immune response against B. miyamotoi that is similar to the response to B. burgdorferi and is able to induce T cell proliferation.


Assuntos
Borrelia/fisiologia , Células Dendríticas/imunologia , Mordeduras e Picadas de Insetos/imunologia , Febre Recorrente/imunologia , Pele/patologia , Linfócitos T/imunologia , Carrapatos/imunologia , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Citocinas/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Ativação Linfocitária , Fagocitose , Carrapatos/microbiologia , Receptor 2 Toll-Like/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-29661882

RESUMO

Borrelia miyamotoi is an emerging relapsing fever (RF) Borrelia species that is reported to cause human disease in regions in which Lyme borreliosis is endemic. We recently showed that B. miyamotoi tick isolates are resistant to amoxicillin in vitro; however, clinical isolates have not been studied. Therefore, our aim was to show the antimicrobial susceptibility of recently obtained clinical isolates of B. miyamotoi A dilution series of various antibiotics was made in modified Kelly-Pettenkofer medium with 10% fetal calf serum. The susceptibilities of different B. miyamotoi clinical, B. miyamotoi tick, RF Borrelia, and Borrelia burgdorferisensu lato isolates were tested by measuring MICs through colorimetric changes and by counting motile spirochetes by dark-field microscopy after 72 h of incubation. The ceftriaxone and azithromycin MIC ranges of the six B. miyamotoi clinical isolates tested were 0.03 to 0.06 mg/liter and 0.0016 to 0.0032 mg/liter, respectively. These values are similar to MICs for RF Borrelia strains and B. miyamotoi tick isolates. All tested RF Borrelia strains were susceptible to doxycycline (microscopic MIC range, 0.0625 to 0.25 mg/liter). In contrast to the MICs of the tested B. burgdorferi sensu lato strains and in line with our previous findings, the amoxicillin MICs (range, 8 to 32 mg/liter) of all RF Borrelia strains, including B. miyamotoi clinical isolates, were above the clinical breakpoint for resistance (≤4 mg/liter). Clinical isolates of B. miyamotoi are highly susceptible to doxycycline, azithromycin, and ceftriaxone in vitro Interestingly, as described previously for tick isolates, amoxicillin shows poor in vitro activity against B. miyamotoi clinical isolates.


Assuntos
Amoxicilina/farmacologia , Antibacterianos/farmacologia , Azitromicina/farmacologia , Borrelia/efeitos dos fármacos , Borrelia/isolamento & purificação , Ceftriaxona/farmacologia , Doxiciclina/farmacologia , Animais , Humanos , Ixodes/microbiologia , Testes de Sensibilidade Microbiana , Febre Recorrente/tratamento farmacológico , Febre Recorrente/microbiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-28674060

RESUMO

Hard-tick-borne relapsing fever (HTBRF) is an emerging infectious disease throughout the temperate zone caused by the relapsing-fever spirochete Borrelia miyamotoi Antibiotic treatment of HTBRF is empirically based on the treatment of Lyme borreliosis; however, the antibiotic susceptibility of B. miyamotoi has not been studied to date. Thus, we set out to determine the in vitro antimicrobial susceptibility of B.miyamotoi A microdilution method with 96-well microtiter plates was used to determine the antibiotic susceptibilities of two B.miyamotoi strains isolated on two different continents (Asia and North America), two Borrelia burgdorferisensu lato strains, and one Borrelia hermsii isolate for purposes of comparison. The MIC and minimal bactericidal concentration (MBC) were determined by both microscopy and colorimetric assays. We were able to show that relative to the B. burgdorferi sensu lato isolates, both B.miyamotoi strains and B. hermsii demonstrated greater susceptibility to doxycycline and azithromycin, equal susceptibility to ceftriaxone, and resistance to amoxicillin in vitro The MIC and MBC of amoxicillin for B. miyamotoi evaluated by microscopy were 16 to 32 mg/liter and 32 to 128 mg/liter, respectively. Since B. miyamotoi is susceptible to doxycycline, azithromycin, and ceftriaxone in vitro, our data suggest that these antibiotics can be used for the treatment of HTBRF. Oral amoxicillin is currently used as an alternative for the treatment of HTBRF; however, since we found that the B. miyamotoi strains tested were resistant to amoxicillin in vitro, this issue warrants further study.


Assuntos
Amoxicilina/farmacologia , Antibacterianos/farmacologia , Azitromicina/farmacologia , Borrelia/efeitos dos fármacos , Ceftriaxona/farmacologia , Doxiciclina/farmacologia , Febre Recorrente/tratamento farmacológico , Animais , Ásia , Borrelia/classificação , Borrelia/isolamento & purificação , Farmacorresistência Bacteriana , Humanos , Camundongos , Testes de Sensibilidade Microbiana , América do Norte , Febre Recorrente/microbiologia
4.
BMC Gastroenterol ; 12: 33, 2012 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-22507600

RESUMO

BACKGROUND: It is believed that inflammatory bowel diseases (IBD) result from an imbalance in the intestinal immune response towards the luminal microbiome. Dectin-1 is a widely expressed pattern recognition receptor that recognizes fungi and upon recognition it mediates cytokine responses and skewing of the adaptive immune system. Hence, dectin-1 may be involved in the pathogenesis of IBD. METHODS: We assessed the responses of dectin-1 deficient macrophages to the intestinal microbiota and determined the course of acute DSS and chronic Helicobacter hepaticus induced colitis in dectin-1 deficient mice. RESULTS: We show that the mouse intestinal microbiota contains fungi and the cytokine responses towards this microbiota were significantly reduced in dectin-1 deficient macrophages. However, in two different colitis models no significant differences in the course of inflammation were found in dectin-1 deficient mice compared to wild type mice. CONCLUSIONS: Together our data suggest that, although at the immune cell level there is a difference in response towards the intestinal flora in dectin-1 deficient macrophages, during intestinal inflammation this response seems to be redundant since dectin-1 deficiency in mice does not affect intestinal inflammation in experimental colitis.


Assuntos
Colite/genética , Colite/imunologia , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Macrófagos/imunologia , Animais , Colite/induzido quimicamente , Colite/microbiologia , Sulfato de Dextrana , Fezes/microbiologia , Helicobacter hepaticus , Interleucina-10/metabolismo , Intestino Grosso/microbiologia , Lipopolissacarídeos/imunologia , Metagenoma , Camundongos , Camundongos Endogâmicos C57BL , Rhodotorula/imunologia , Ácidos Teicoicos/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Zimosan/imunologia
5.
PLoS Pathog ; 5(5): e1000447, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19461880

RESUMO

The causative agent of Lyme borreliosis, the spirochete Borrelia burgdorferi, has been shown to induce expression of the urokinase receptor (uPAR); however, the role of uPAR in the immune response against Borrelia has never been investigated. uPAR not only acts as a proteinase receptor, but can also, dependently or independently of ligation to uPA, directly affect leukocyte function. We here demonstrate that uPAR is upregulated on murine and human leukocytes upon exposure to B. burgdorferi both in vitro as well as in vivo. Notably, B. burgdorferi-inoculated C57BL/6 uPAR knock-out mice harbored significantly higher Borrelia numbers compared to WT controls. This was associated with impaired phagocytotic capacity of B. burgdorferi by uPAR knock-out leukocytes in vitro. B. burgdorferi numbers in vivo, and phagocytotic capacity in vitro, were unaltered in uPA, tPA (low fibrinolytic activity) and PAI-1 (high fibrinolytic activity) knock-out mice compared to WT controls. Strikingly, in uPAR knock-out mice partially backcrossed to a B. burgdorferi susceptible C3H/HeN background, higher B. burgdorferi numbers were associated with more severe carditis and increased local TLR2 and IL-1beta mRNA expression. In conclusion, in B. burgdorferi infection, uPAR is required for phagocytosis and adequate eradication of the spirochete from the heart by a mechanism that is independent of binding of uPAR to uPA or its role in the fibrinolytic system.


Assuntos
Borrelia burgdorferi/imunologia , Doença de Lyme/imunologia , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Animais , Artrite Infecciosa/microbiologia , Movimento Celular , Coração/microbiologia , Histocitoquímica , Humanos , Leucócitos/metabolismo , Doença de Lyme/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocardite/microbiologia , Fagocitose , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética , Pele/metabolismo , Pele/microbiologia , Estatísticas não Paramétricas , Regulação para Cima , Bexiga Urinária/metabolismo , Bexiga Urinária/microbiologia , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
7.
Sci Rep ; 9(1): 1431, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30723261

RESUMO

The causative agents of Lyme borreliosis, spirochetes belonging to the Borrelia burgdorferi sensu lato group, have developed several ways to protect themselves against killing by the host complement system. In addition, it has been shown that serum sensitive isolates are (partially) protected by the Ixodes Tick Salivary Lectin Pathway Inhibitor (TSLPI) protein; a salivary gland protein that inhibits the function of Mannose Binding Lectin (MBL). MBL is a C-type lectin that recognizes oligosaccharides on pathogens and activates the complement system via the lectin pathway. MBL deficiency has been linked to a more severe course of several infectious diseases and humans with detectable antibodies against B. burgdorferi are significantly more often MBL deficient compared to humans without antibodies against B. burgdorferi. Here we set out to investigate the role of MBL in the immune response against B. burgdorferi in more detail. We demonstrate that B. burgdorferi N40 needle-infected C57BL/6 MBL deficient mice harbored significantly higher B. burgdorferi numbers in skin tissue during the early course of infection. In line with these findings they also developed higher anti-B. burgdorferi IgG serum antibodies compared to WT controls. In contrast, B. burgdorferi loads in distant tissue such as heart, joints or bladder at later time points were similar for both mouse strains. These in vivo findings were corroborated using a B. burgdorferi N40-infected I. scapularis infestation model. We showed that MBL is capable of binding B. burgdorferi through its carbohydrate recognition domains, but in vitro complement killing assays, peritoneal macrophage and whole blood stimulations, phagocytosis assays and an in vivo migration experiment did not reveal the mechanism by which MBL facilitates early clearance of B. burgdorferi. To conclude, we show a protective role of MBL in the early stages of B. burgdorferi infection, yet the underlying mechanism warrants further investigation.


Assuntos
Borrelia burgdorferi/imunologia , Doença de Lyme/imunologia , Lectinas de Ligação a Manose/metabolismo , Fagocitose , Animais , Carga Bacteriana , Borrelia burgdorferi/patogenicidade , Células Cultivadas , Feminino , Coração/microbiologia , Humanos , Imunoglobulina G/imunologia , Articulações/microbiologia , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Polissacarídeos Bacterianos/metabolismo , Ligação Proteica , Bexiga Urinária/microbiologia
8.
Immunobiology ; 223(11): 694-698, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30056999

RESUMO

Myeloid-related protein (MRP)8 and MRP14 form a complex (MRP8/14) that is released by activated neutrophils and monocytes during infection. MRP8/14 has been shown to have bacteriostatic activity in vitro against Borrelia burgdorferi, the spirochete that causes Lyme borreliosis. Furthermore, levels of MRP8/14 have been shown to be elevated in the joints of patients with Lyme arthritis. We hypothesized that MRP8/14 has a protective effect during B. burgdorferi infection. To determine the role of MRP8/14 in the immune response to B. burgdorferi, we studied the course of B. burgdorferi infection in wildtype (wt) and mrp14-/- mice. In addition, we studied the response of leukocytes from mice lacking MRP8/14 to B. burgdorferi ex vivo. We demonstrated similar levels of B. burgdorferi dissemination, cytokine and immunoglobulin production in infected wt and mrp14-/- mice after 21 days. Neutrophils and monocytes lacking MRP8/14 were undiminished in their ability to become activated or phagocytose B. burgdorferi. In conclusion, we did not find a central role of MRP8/14 in the immune response against B. burgdorferi. As the levels of MRP8/14 in the serum of infected mice were low, we speculate that MRP8/14 is not released in levels great enough to influence the course of B. burgdorferi infection.


Assuntos
Borrelia burgdorferi/fisiologia , Calgranulina A/metabolismo , Calgranulina B/metabolismo , Doença de Lyme/imunologia , Monócitos/imunologia , Neutrófilos/imunologia , Animais , Calgranulina A/genética , Calgranulina B/genética , Modelos Animais de Doenças , Feminino , Humanos , Imunidade Inata , Doença de Lyme/transmissão , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fagocitose
9.
Parasit Vectors ; 9: 97, 2016 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-26896940

RESUMO

BACKGROUND: Lyme borreliosis is the most common tick-borne human disease and is caused by Borrelia burgdorferi sensu lato (s.l.). Borrelia miyamotoi, a relapsing fever spirochaete, is transmitted transovarially, whereas this has not been shown for B. burgdorferi (s.l). Therefore, B. burgdorferi (s.l) is considered to cycle from nymphs to larvae through vertebrates. Larvae of Ixodes ricinus are occasionally B. burgdorferi (s.l) infected, but their vector competence has never been studied. METHODS: We challenged 20 laboratory mice with field-collected larvae of I. ricinus. A subset of these larvae was analysed for infections with B. burgdorferi (s.l) and B. miyamotoi. After three to four challenges, mice were sacrificed and skin and spleen samples were analysed for infection by PCR and culture. RESULTS: Field-collected larvae were naturally infected with B. burgdorferi (s.l) (0.62%) and B. miyamotoi (2.0%). Two mice acquired a B. afzelii infection and four mice acquired a B. miyamotoi infection during the larval challenges. CONCLUSION: We showed that larvae of I. ricinus transmit B. afzelii and B. miyamotoi to rodents and calculated that rodents have a considerable chance of acquiring infections from larvae compared to nymphs. As a result, B. afzelii can cycle between larvae through rodents. Our findings further imply that larval bites on humans, which easily go unnoticed, can cause Lyme borreliosis and Borrelia miyamotoi disease.


Assuntos
Borrelia/isolamento & purificação , Transmissão de Doença Infecciosa , Ixodes/microbiologia , Doença de Lyme/transmissão , Animais , Modelos Animais de Doenças , Larva/microbiologia , Camundongos , Pele/microbiologia , Baço/microbiologia
10.
Vector Borne Zoonotic Dis ; 16(4): 223-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26901751

RESUMO

INTRODUCTION: We previously identified tick salivary lectin pathway inhibitor (TSLPI) in Ixodes scapularis, a vector for Borrelia burgdorferi sensu stricto (s.s.) in North America. TSLPI is a salivary protein facilitating B. burgdorferi s.s. transmission and acquisition by inhibiting the host lectin complement pathway through interference with mannose binding lectin (MBL) activity. Since Ixodes ricinus is the predominant vector for Lyme borreliosis in Europe and transmits several complement sensitive B. burgdorferi sensu lato (s.l.) strains, we aimed to identify, describe, and characterize the I. ricinus ortholog of TSLPI. METHODS: We performed (q)PCRs on I. ricinus salivary gland cDNA to identify a TSLPI ortholog. Next, we generated recombinant (r)TSLPI in a Drosophila expression system and examined inhibition of the MBL complement pathway and complement-mediated killing of B. burgdorferi s.l. in vitro. RESULTS: We identified a TSLPI ortholog in I. ricinus salivary glands with 93% homology at the RNA and 89% at the protein level compared to I. scapularis TSLPI, which was upregulated during tick feeding. In silico analysis revealed that TSLPI appears to be part of a larger family of Ixodes salivary proteins among which I. persulcatus basic tail salivary proteins and I. scapularis TSLPI and Salp14. I. ricinus rTSLPI inhibited the MBL complement pathway and protected B. burgdorferi s.s. and Borrelia garinii from complement-mediated killing. CONCLUSION: We have identified a TSLPI ortholog, which protects B. burgdorferi s.l. from complement-mediated killing in I. ricinus, the major vector for tick-borne diseases in Europe.


Assuntos
Proteínas de Artrópodes/biossíntese , Grupo Borrelia Burgdorferi/fisiologia , Ixodes/metabolismo , Glândulas Salivares/metabolismo , Proteínas e Peptídeos Salivares/biossíntese , Animais , Vetores Aracnídeos/metabolismo , Vetores Aracnídeos/microbiologia , Lectina de Ligação a Manose da Via do Complemento , Humanos , Ixodes/genética , Ixodes/microbiologia , Doença de Lyme/imunologia , Doença de Lyme/metabolismo , Doença de Lyme/transmissão , Glândulas Salivares/microbiologia
11.
J Mol Med (Berl) ; 94(3): 361-70, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26594018

RESUMO

The causative agent of Lyme borreliosis, Borrelia burgdorferi, is transmitted by Ixodes ticks. During tick feeding, B. burgdorferi migrates from the tick gut to the salivary glands from where transmission to the host occurs. B. burgdorferi-interacting tick proteins might serve as vaccine targets to thwart B. burgdorferi transmission. A previous screening for B. burgdorferi-interacting Ixodes scapularis gut proteins identified an I. scapularis putative dystroglycan protein (ISCW015049). Here, we describe the ISCW015049's protein structure and its cellular location in the tick gut in relation to B. burgdorferi migration. Secondly, in vivo B. burgdorferi-tick attachment murine models were performed to study the role of ISCW015049 during B. burgdorferi migration and transmission. In silico analysis confirmed that ISCW015049 is similar to dystroglycan and was named I. scapularis dystroglycan-like protein (ISDLP). Confocal microscopy of gut tissue showed that ISDLP is expressed on the surface of gut cells, is upregulated during tick feeding, and is expressed significantly higher in infected ticks compared to uninfected ticks. Inhibition of ISDLP by RNA interference (RNAi) resulted in lower B. burgdorferi transmission to mice. In conclusion, we have identified a dystroglycan-like protein in I. scapularis gut that can bind to B. burgdorferi and promotes B. burgdorferi migration from the tick gut. Key messages: B. burgdorferi exploits tick proteins to orchestrate its transmission to the host. B. burgdorferi is able bind to an I. scapularis dystroglycan-like protein (ISDLP). Inhibition of ISDLP in ticks results in lower B. burgdorferi transmission to mice. ISDLP is a potential target to prevent Lyme borreliosis.


Assuntos
Proteínas de Artrópodes/metabolismo , Borrelia burgdorferi/fisiologia , Distroglicanas/metabolismo , Ixodes/microbiologia , Doença de Lyme/prevenção & controle , Doença de Lyme/transmissão , Animais , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/uso terapêutico , Distroglicanas/genética , Distroglicanas/uso terapêutico , Humanos , Imunização , Ixodes/genética , Ixodes/fisiologia , Doença de Lyme/metabolismo , Vacinas contra Doença de Lyme/genética , Vacinas contra Doença de Lyme/metabolismo , Vacinas contra Doença de Lyme/uso terapêutico , Camundongos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/uso terapêutico , Terapêutica com RNAi , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/uso terapêutico
12.
PLoS One ; 11(10): e0164040, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27695100

RESUMO

Borrelia burgdorferi is transmitted into the skin of the host where it encounters and interacts with two dendritic cell (DC) subsets; Langerhans cells (LCs) and dermal DCs (DDCs). These cells recognize pathogens via pattern recognition receptors, mature and migrate out of the skin into draining lymph nodes, where they orchestrate adaptive immune responses. In order to investigate the response of skin DCs during the early immunopathogenesis of Lyme borreliosis, we injected B. burgdorferi intradermally into full-thickness human skin and studied the migration of DCs out of the skin, the activation profile and phenotype of migrated cells. We found a significant increase in the migration of LCs and DDCs in response to B. burgdorferi. Notably, migration was prevented by blocking TLR2. DCs migrated from skin inoculated with higher numbers of spirochetes expressed significantly higher levels of CD83 and produced pro-inflammatory cytokines. No difference was observed in the expression of HLA-DR, CD86, CD38, or CCR7. To conclude, we have established an ex vivo human skin model to study DC-B. burgdorferi interactions. Using this model, we have demonstrated that B. burgdorferi-induced DC migration is mediated by TLR2. Our findings underscore the utility of this model as a valuable tool to study immunity to spirochetal infections.


Assuntos
Borrelia burgdorferi/fisiologia , Movimento Celular/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Receptor 2 Toll-Like/metabolismo , Biomarcadores , Sobrevivência Celular , Citocinas/metabolismo , Humanos , Doença de Lyme/imunologia , Doença de Lyme/metabolismo , Doença de Lyme/microbiologia , Pele/imunologia , Pele/metabolismo , Pele/microbiologia
13.
Immunobiology ; 220(10): 1141-50, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26093919

RESUMO

Borrelia burgdorferi can be categorized based on restriction fragment length polymorphism analysis into ribosomal spacer type (RST) 1, 2 and 3. A correlation between RST type and invasiveness of Borrelia isolates has been demonstrated in clinical studies and experimental models, and RST 1 isolates are more likely to cause disseminated disease than RST 3 isolates. We hypothesized that this could partially be due to increased susceptibility of RST 3 isolates to killing by the innate immune system early in infection. Thus, we investigated the interaction of five RST 1 and five RST 3 isolates with various components of the human innate immune system in vitro. RST 3 isolates induced significantly greater upregulation of activation markers in monocyte-derived dendritic cells compared to RST 1 isolates at a low multiplicity of infection. However, RST 1 isolates stimulated greater interleukin-6 production. At a high multiplicity of infection no differences in dendritic cell activation or cytokine production were observed. In addition, we observed no differences in the ability of RST 1 and RST 3 isolates to activate monocytes or neutrophils and all strains were phagocytosed at a comparable rate. Finally, all isolates tested were equally resistant to complement-mediated killing, as determined by dark-field microscopy and a growth inhibition assay. In conclusion, we demonstrate that the RST 1 and 3 isolates showed no distinction in their susceptibility to the various components of the human immune system studied here, suggesting that other factors are responsible for their differential invasiveness.


Assuntos
Borrelia burgdorferi/imunologia , Genótipo , Imunidade Inata , Interleucina-6/imunologia , Doença de Lyme/imunologia , Borrelia burgdorferi/genética , Borrelia burgdorferi/isolamento & purificação , Proteínas do Sistema Complemento/imunologia , Feminino , Humanos , Doença de Lyme/genética , Doença de Lyme/patologia , Masculino
14.
Parasit Vectors ; 7: 418, 2014 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-25189195

RESUMO

BACKGROUND: Borrelia miyamotoi is a relapsing fever spirochete found in Ixodes ticks in North America, Europe, and Asia, and has recently been found to be invasive in humans. Cultivation of this spirochete has not yet been described, but is important for patient diagnostics and scientific purposes. Host specificity of Borrelia species is dependent on resistance to host complement (serum resistance), and since B. miyamotoi has been identified as a human pathogen we were interested whether B. miyamotoi is resistant to human complement. METHODS: We inoculated B. miyamotoi strains LB-2001 and HT31 in modified-Kelly-Pettenkofer medium with 10% fetal calf serum (MKP-F), and used standard non-laborious Borrelia culture methods to culture the spirochetes. Next, we assessed serum sensitivity by a direct killing assay and a growth inhibition assay. RESULTS: We were able to passage B. miyamotoi over 10 times using a standard culture method in MKP-F medium, and found B. miyamotoi to be resistant to human complement. In contrast to B. miyamotoi, Borrelia anserina--a relapsing fever spirochete unrelated to human infection--was serum sensitive. CONCLUSIONS: Using a variation on MKP medium we were able to culture B. miyamotoi, opening the door to in vitro research into this spirochete. In addition, we describe that B. miyamotoi is resistant to human complement, which might play an important role in pathogenesis. We have also found B. anserina to be sensitive to human complement, which might explain why it is not related to human infection. Summarizing, we describe a novel culture method for B. miyamotoi and show it is resistant to human complement.


Assuntos
Borrelia/classificação , Borrelia/fisiologia , Proteínas do Sistema Complemento/farmacologia , Meios de Cultura/química , Técnicas Bacteriológicas , Borrelia/efeitos dos fármacos , Humanos , Fatores de Tempo
15.
Cell Host Microbe ; 10(2): 136-46, 2011 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-21843870

RESUMO

The Lyme disease agent Borrelia burgdorferi is primarily transmitted to vertebrates by Ixodes ticks. The classical and alternative complement pathways are important in Borrelia eradication by the vertebrate host. We recently identified a tick salivary protein, designated P8, which reduced complement-mediated killing of Borrelia. We now discover that P8 interferes with the human lectin complement cascade, resulting in impaired neutrophil phagocytosis and chemotaxis and diminished Borrelia lysis. Therefore, P8 was renamed the tick salivary lectin pathway inhibitor (TSLPI). TSLPI-silenced ticks, or ticks exposed to TSLPI-immune mice, were hampered in Borrelia transmission. Moreover, Borrelia acquisition and persistence in tick midguts was impaired in ticks feeding on TSLPI-immunized, B. burgdorferi-infected mice. Together, our findings suggest an essential role for the lectin complement cascade in Borrelia eradication and demonstrate how a vector-borne pathogen co-opts a vector protein to facilitate early mammalian infection and vector colonization.


Assuntos
Borrelia burgdorferi/patogenicidade , Lectina de Ligação a Manose da Via do Complemento , Proteínas de Insetos/imunologia , Ixodes/microbiologia , Doença de Lyme/transmissão , Sequência de Aminoácidos , Animais , Borrelia burgdorferi/imunologia , Ensaios de Migração Celular , Clonagem Molecular , Complexo de Ataque à Membrana do Sistema Complemento/imunologia , Feminino , Inativação Gênica , Hemólise/imunologia , Humanos , Imunização Passiva , Imunoterapia Ativa , Proteínas de Insetos/farmacologia , Larva/microbiologia , Doença de Lyme/imunologia , Doença de Lyme/microbiologia , Camundongos , Camundongos Endogâmicos C3H , Dados de Sequência Molecular , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Ninfa/microbiologia , Fagocitose , Coelhos , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Saliva/imunologia , Saliva/microbiologia , Proteínas e Peptídeos Salivares/imunologia , Proteínas e Peptídeos Salivares/farmacologia , Alinhamento de Sequência
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