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Oosting M, Buffen K, van der Meer JWM, Netea MG, Joosten LAB. Innate immunity networks during infection with Borrelia burgdorferi. Crit Rev Microbiol 2014; 42:233-44. [PMID: 24963691 DOI: 10.3109/1040841x.2014.929563] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The recognition of Borrelia species represents a complex process in which multiple components of the immune system are involved. In this review, we summarize the interplay between the host innate system and Borrelia spp., from the recognition by pattern recognition receptors (PRRs) to the induction of a complex network of proinflammatory mediators. Several PRR families are crucial for recognition of Borrelia spp., including Toll-like receptors (TLRs) and Nucleotide Oligomerization Domain (NOD)-like receptors (NLRs). TLR-2 is crucial for the recognition of outer surface protein (Osp)A from Borrelia spp. and together with TLR8 mediates phagocytosis of the microorganism and production of type I interferons. Intracellular receptors such as TLR7, TLR8 and TLR9 on the one hand and the NLR receptor NOD2 on the other hand, represent the second major recognition system of Borrelia. PRR-dependent signals induce the release of pro-inflammatory cytokines such as interleukin-1 and T-helper-derived cytokines, which are thought to mediate the inflammation during Lyme disease. Understanding the regulation of host defense mechanisms against Borrelia has the potential to lead to the discovery of novel immunotherapeutic targets to improve the therapy against Lyme disease.
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Affiliation(s)
- Marije Oosting
- a Department of Internal Medicine , and.,b Nijmegen Institute of Infection, Inflammation and Immunity (N4i), Radboud University Medical Centre , Nijmegen , The Netherlands
| | - Kathrin Buffen
- a Department of Internal Medicine , and.,b Nijmegen Institute of Infection, Inflammation and Immunity (N4i), Radboud University Medical Centre , Nijmegen , The Netherlands
| | - Jos W M van der Meer
- a Department of Internal Medicine , and.,b Nijmegen Institute of Infection, Inflammation and Immunity (N4i), Radboud University Medical Centre , Nijmegen , The Netherlands
| | - Mihai G Netea
- a Department of Internal Medicine , and.,b Nijmegen Institute of Infection, Inflammation and Immunity (N4i), Radboud University Medical Centre , Nijmegen , The Netherlands
| | - Leo A B Joosten
- a Department of Internal Medicine , and.,b Nijmegen Institute of Infection, Inflammation and Immunity (N4i), Radboud University Medical Centre , Nijmegen , The Netherlands
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Cervantes JL, Hawley KL, Benjamin SJ, Weinerman B, Luu SM, Salazar JC. Phagosomal TLR signaling upon Borrelia burgdorferi infection. Front Cell Infect Microbiol 2014; 4:55. [PMID: 24904837 PMCID: PMC4033037 DOI: 10.3389/fcimb.2014.00055] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 04/09/2014] [Indexed: 12/31/2022] Open
Abstract
Internalization and degradation of live Bb within phagosomal compartments of monocytes, macrophages and dendritic cells (DCs), allows for the release of lipoproteins, nucleic acids and other microbial products, triggering a broad and robust inflammatory response. Toll-like receptors (TLRs) are key players in the recognition of spirochetal ligands from whole viable organisms (i.e., vita-PAMPs). Herein we will review the role of endosomal TLRs in the response to the Lyme disease spirochete.
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Affiliation(s)
- Jorge L Cervantes
- Department of Pediatrics, University of Connecticut Health Center Farmington, CT, USA ; Division of Infectious Diseases, Connecticut Children's Medical Center Hartford, CT, USA
| | - Kelly L Hawley
- Department of Pediatrics, University of Connecticut Health Center Farmington, CT, USA ; Division of Infectious Diseases, Connecticut Children's Medical Center Hartford, CT, USA
| | - Sarah J Benjamin
- Department of Pediatrics, University of Connecticut Health Center Farmington, CT, USA
| | - Bennett Weinerman
- Department of Pediatrics, University of Connecticut Health Center Farmington, CT, USA
| | - Stephanie M Luu
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center Farmington, CT, USA
| | - Juan C Salazar
- Department of Pediatrics, University of Connecticut Health Center Farmington, CT, USA ; Division of Infectious Diseases, Connecticut Children's Medical Center Hartford, CT, USA ; Department of Immunology, University of Connecticut Health Center Farmington, CT, USA
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Codolo G, Bossi F, Durigutto P, Bella CD, Fischetti F, Amedei A, Tedesco F, D'Elios S, Cimmino M, Micheletti A, Cassatella MA, D'Elios MM, de Bernard M. Orchestration of inflammation and adaptive immunity in Borrelia burgdorferi-induced arthritis by neutrophil-activating protein A. ACTA ACUST UNITED AC 2013; 65:1232-42. [PMID: 23371320 DOI: 10.1002/art.37875] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 01/15/2013] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Lyme arthritis (LA) is characterized by infiltration of inflammatory cells, mainly neutrophils (polymorphonuclear cells [PMNs]) and T cells, into the joints. This study was undertaken to evaluate the role of the neutrophil-activating protein A (NapA) of Borrelia burgdorferi in eliciting inflammation and in driving the adaptive immune response. METHODS Levels of NapA, interferon-γ (IFNγ), interleukin-17 (IL-17), and T cell-attracting chemokines were assessed by enzyme-linked immunosorbent assay in synovial fluid from patients with LA. The profile of T cells recruited into the synovia of patients with LA was defined by fluorescence-activated cell sorting analysis. NapA was intraarticularly injected into rat knees, and the cells recruited in synovia were characterized. The role of NapA in recruiting immune cells was confirmed by chemotaxis assays using a Transwell system. RESULTS NapA, IFNγ, IL-17, CCL2, CCL20, and CXCL10 accumulated in synovial fluid from patients with LA. Accordingly, T cells obtained from these patients produced IFNγ or IL-17, but notably, some produced both cytokines. NapA promoted neutrophil and T lymphocyte recruitment both in vitro and in vivo. Interestingly, the infiltration of T cells not only resulted from the chemotactic activity of NapA but also relied on the chemokines produced by PMNs exposed to NapA. CONCLUSION We provide evidence that NapA functions as one of the main bacterial products involved in the pathogenesis of LA. Accordingly, we show that, at very early stages of LA, NapA accumulates and, in turn, orchestrates the recruitment of inflammatory cells into the joint cavity. Thereafter, with the contribution of recruited cells, NapA promotes the infiltration of T cells producing IL-17 and/or IFNγ.
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Affiliation(s)
- Gaia Codolo
- Venetian Institute of Molecular Medicine and University of Padua, Padua, Italy
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Borrelia burgdorferiNapA-driven Th17 cell inflammation in lyme arthritis. ACTA ACUST UNITED AC 2008; 58:3609-17. [DOI: 10.1002/art.23972] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Knauer J, Siegemund S, Müller U, Al-Robaiy S, Kastelein RA, Alber G, Straubinger RK. Borrelia burgdorferipotently activates bone marrow-derived conventional dendritic cells for production of IL-23 required for IL-17 release by T cells. ACTA ACUST UNITED AC 2007; 49:353-63. [PMID: 17378899 DOI: 10.1111/j.1574-695x.2006.00210.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Lyme borreliosis is characterized by cellular inflammatory responses at multiple body sites. Recently, an association of interleukin-17 (IL-17) and Lyme arthritis was suggested. In this context, it is of special interest that the heterodimeric cytokine IL-23 can act on T cells and initiate the up-regulation of effector cytokines such as IL-17. To determine the role of this specific cytokine cascade for the induction of subsequently induced proinflammatory events we developed an in vitro system to investigate the IL-23-inducing capacity of Borrelia burgdorferi and the potential of the spirochete for inducing the IL-23/IL-17 axis. We used cells derived from mice deficient for IL-23 or IL-12 only or deficient for both IL-12 and IL-23 to define precisely the function of these cytokines. Experiments with bone marrow-derived dendritic cells (BMDC) identified these cells as sources for IL-23 but not for IL-12 after B. burgdorferi exposure. Subsequent investigations with T cell-depleted splenocyte fractions revealed a tight IL-23/IL-17 axis in response to the spirochetes. Monoclonal antibodies that block IL-23 showed further that BMDC-derived IL-23 was required for production of IL-17 in this experimental model. These in vitro data describing a spirochete-induced release of IL-23 may help to define IL-17-dependent inflammatory responses in the disease.
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Affiliation(s)
- Jens Knauer
- Institute of Immunology, College of Veterinary Medicine, University of Leipzig, Leipzig, Germany
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Abstract
Lyme borreliosis in humans is an inflammatory disease affecting multiple organ systems, including the nervous system, cardiovascular system, joints and muscles. The causative agent, the spirochaete Borrelia burgdorferi, is transmitted to the host by a tick bite. The pathogenesis of the disease in its early stages is associated largely with the presence of viable bacteria at the site of inflammation, whereas in the later stages of disease, autoimmune features seem to contribute significantly. In addition, it has been suggested that chronic persistence of B. burgdorferi in affected tissues is of pathogenic relevance. Long-term exposure of the host immune system to spirochaetes and/or borrelial compounds may induce chronic autoimmune disease. The study of bacterium-host interactions has revealed a variety of proinflammatory and also immunomodulatory-immunosuppressive features caused by the pathogen. Therapeutic strategies using antibiotics are generally successful, but chronic disease may require immunosuppressive treatment. Effective and safe vaccines using recombinant outer surface protein A have been developed, but have not been propagated because of fears that autoimmunity might be induced. Nevertheless, new insights into the modes of transmission of B. burgdorferi to the warm-blooded host have been generated by studying the action of these vaccines.
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Affiliation(s)
- S K Singh
- Paediatric Rheumatology, Children's Hospital, University of Würzburg, Würzburg, Germany
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Straubinger RK, Straubinger AF, Summers BA, Erb HN, Härter L, Appel MJ. Borrelia burgdorferi induces the production and release of proinflammatory cytokines in canine synovial explant cultures. Infect Immun 1998; 66:247-58. [PMID: 9423865 PMCID: PMC107884 DOI: 10.1128/iai.66.1.247-258.1998] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Canine synovial membrane explants were exposed to high- or low-passage Borrelia burgdorferi for 3, 6, 12, and 24 h. Spirochetes received no treatment, were UV light irradiated for 16 h, or were sonicated prior to addition to synovial explant cultures. In explant tissues, mRNA levels for the proinflammatory cytokines tumor necrosis factor alpha (TNF-alpha), interleukin-1alpha (IL-1alpha), IL-1beta, and IL-8 were surveyed semiquantitatively by reverse transcription-PCR. Culture supernatants were examined for numbers of total and motile (i.e., viable) spirochetes, TNF-like and IL-1-like activities, polymorphonuclear neutrophil (PMN) chemotaxis-inducing activities, and IL-8. During exposure to synovial explant tissues, the total number of spirochetes in the supernatants decreased gradually by approximately 30%, and the viability also declined. mRNAs for TNF-alpha, IL-1alpha, IL-1beta, and IL-8 were up-regulated in synovial explant tissues within 3 h after infection with untreated or UV light-irradiated B. burgdorferi, and mRNA levels corresponded to the results obtained with bioassays. During 24 h of coincubation, cultures challenged with untreated or UV light-irradiated spirochetes produced similar levels of TNF-like and IL-1-like activities. In contrast, explant tissues exposed to untreated B. burgdorferi generated significantly higher levels of chemotactic factors after 24 h of incubation than did explant tissues exposed to UV light-treated spirochetes. In identical samples, a specific signal for IL-8 was identified by Western blot analysis. High- and low-passage borreliae did not differ in their abilities to induce proinflammatory cytokines. No difference in cytokine induction between untreated and sonicated high-passage spirochetes was observed, suggesting that fractions of the organism can trigger the production and release of inflammatory mediators. The titration of spirochetes revealed a dose-independent cytokine response, where 10(3) to 10(7) B. burgdorferi organisms induced similar TNF-like activities but only 10(7) spirochetes induced measurable IL-1-like activities. The release of chemotactic factors was dose dependent and was initiated when tissues were infected with at least 10(5) organisms. We conclude that intact B. burgdorferi or fractions of the bacterium can induce the local up-regulation of TNF-alpha, IL-1alpha, and IL-1beta in the synovium but that the interaction of viable spirochetes with synovial cells leads to the release of IL-8, which probably is a prime initiator of PMN migration during acute Lyme arthritis.
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Affiliation(s)
- R K Straubinger
- James A. Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853, USA.
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Burns MJ, Sellati TJ, Teng EI, Furie MB. Production of interleukin-8 (IL-8) by cultured endothelial cells in response to Borrelia burgdorferi occurs independently of secreted [corrected] IL-1 and tumor necrosis factor alpha and is required for subsequent transendothelial migration of neutrophils. Infect Immun 1997; 65:1217-22. [PMID: 9119454 PMCID: PMC175120 DOI: 10.1128/iai.65.4.1217-1222.1997] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Previous studies have shown that Borrelia burgdorferi, the spirochetal agent of Lyme disease, promotes inflammation by stimulating endothelial cells to upregulate adhesion molecules for leukocytes and to produce a soluble agent that is chemotactic for neutrophils. We determined that interleukin-8 (IL-8) was the chemotactic agent for neutrophils present in conditioned media from cultured human umbilical vein endothelial cells stimulated with B. burgdorferi. As few as one spirochete per endothelial cell stimulated production of IL-8 within 8 h of coincubation. When 10 spirochetes per endothelial cell were added, IL-8 was detected after 4 h of coculture. Production of IL-8 continued in a linear fashion for at least 24 h. Neutralizing antibodies against IL-8 reduced migration of neutrophils across spirochete-stimulated endothelial monolayers by 93%. In contrast, pretreatment of neutrophils with antagonists of platelet-activating factor did not inhibit migration. Increases in production of IL-8 and expression of the adhesion molecule E-selectin by endothelial cells in response to B. burgdorferi were not inhibited by IL-1 receptor antagonist or a neutralizing monoclonal antibody directed against tumor necrosis factor alpha, used either alone or in combination. These results suggest that activation of endothelium by B. burgdorferi is not mediated through the autocrine action of secreted IL-1 or tumor necrosis factor alpha. Rather, it appears that B. burgdorferi must stimulate endothelium either by a direct signaling mechanism or by induction of a novel host-derived proinflammatory cytokine.
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Affiliation(s)
- M J Burns
- Department of Pathology, School of Medicine, State University of New York at Stony Brook 11794, USA.
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Straubinger RK, Straubinger AF, Härter L, Jacobson RH, Chang YF, Summers BA, Erb HN, Appel MJ. Borrelia burgdorferi migrates into joint capsules and causes an up-regulation of interleukin-8 in synovial membranes of dogs experimentally infected with ticks. Infect Immun 1997; 65:1273-85. [PMID: 9119462 PMCID: PMC175128 DOI: 10.1128/iai.65.4.1273-1285.1997] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Twenty 6-week-old specific-pathogen-free beagles were infected with Borrelia burgdorferi by tick challenge, and five uninfected dogs served as controls. During the study, all dogs were monitored for infection, clinical signs, and antibody response against B. burgdorferi. During episodes of lameness or postmortem, synovial fluids from each dog were examined for volume, cell number, polymorphonuclear leukocyte (PMN) content, cell viability, and chemotactic activity. Twenty-five tissues collected postmortem from each dog were tested for interleukin-8 (IL-8) mRNA, tumor necrosis factor alpha (TNF-alpha) mRNA, presence of live spirochetes, and histopathological changes. Thirteen infected dogs (group A), which seroconverted rapidly (maximum titers within 50 to 90 days), developed acute and severe mono- or oligoarthritis almost exclusively in the limb closest to the tick bite (median incubation period, 66 days). Synovial fluids of the arthritic joints collected during episodes of lameness had significantly elevated volume, cell count, PMN proportion, cell viability, and chemotactic activity for PMNs. The remaining joints of the same animals contained synovial fluids with elevated chemotactic activity and cell viability. Twelve dogs tested positive for IL-8 mRNA in multiple tissues (synovia, pericardium, and peritoneum), and 10 dogs expressed TNF-alpha mRNA, but only in the tributary lymph nodes of the inflamed joints. Histological examinations revealed severe poly- or oligoarthritis and moderate to severe cortical hyperplasia in draining lymph nodes of the inflamed joints in all 13 dogs. Seven infected dogs with mild or no clinical signs (group B) seroconverted slowly (peak titers after 90 days), and only some joint fluids showed chemotactic activity, which on average was lower than that in inflamed and noninflamed joints from dogs in group A. Four dogs expressed IL-8 mRNA (in the synovia and pericardium), and three dogs had TNF-alpha mRNA in tributary lymph nodes. Histologically, nonsuppurative arthritis was found in multiple joints, and mild to moderate cortical hyperplasia was found in draining lymph nodes. Five uninfected dogs without lameness (group C) had normal synovial fluids and tissues. In all infected dogs, live spirochetes were demonstrated more frequently in tissues of the somatic quadrant closest to the tick bite than in tissues further from the site of infection, suggesting that dissemination of B. burgdorferi occurs more by migration than by blood-borne spread. From these studies employing a canine model of B. burgdorferi infection, we conclude that IL-8 is involved in the pathogenesis of acute Lyme arthritis.
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Affiliation(s)
- R K Straubinger
- James A. Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853, USA.
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Abstract
Lyme disease, caused by Borrelia burgdorferi, causes a multisystem inflammatory ailment, although the precise means of tissue damage are not well understood. It is clear that the organism is present at the site of inflammation in many organs and that many of the features of the illness are relieved by antibiotic therapy. A complex interaction between spirochete and immune systems of a number of mammalian hosts, in human disease and animal models, has been described. It is clear that T cells and macrophages are intimately associated with the pathogenesis of arthritis and that immune mechanisms are involved in other aspects of disease. Inflammation directed at persistence of Borrelial antigens is a plausible explanation for persisting arthritis. Autoimmunity based on molecular mimicry may play a role in the pathogenesis of Lyme disease. Humoral immunity plays a protective role, prompting interest in vaccine development. Significant variation in certain of the outer surface proteins suggests that multiple proteins, peptides, or chimeric vaccines may be needed to provide a sufficiently broad humoral protective response.
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Affiliation(s)
- L H Sigal
- Division of Rheumatology and Connective Tissue Research, UMDNJ-Robert Wood Johnson Medical School, New Brunswick 08903, USA
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Sellati TJ, Abrescia LD, Radolf JD, Furie MB. Outer surface lipoproteins of Borrelia burgdorferi activate vascular endothelium in vitro. Infect Immun 1996; 64:3180-7. [PMID: 8757851 PMCID: PMC174205 DOI: 10.1128/iai.64.8.3180-3187.1996] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Previously, we reported that activation of vascular endothelium by the Lyme disease pathogen Borrelia burgdorferi results in enhanced expression of endothelial cell adhesion molecules and promotion of the transendothelial migration of neutrophils in vitro. To investigate the role of spirochetal lipoproteins in this process, we assessed the ability of a synthetic lipohexapeptide corresponding to the N terminus of B. burgdorferi outer surface protein A (OspA) to activate human umbilical vein endothelial cells (HUVEC). Using a whole-cell enzyme-linked immunosorbent assay, we demonstrated that OspA lipopeptide activated endothelium in a dose-dependent fashion, as measured by upregulation of E-selectin. Near-maximal stimulation was achieved with 100 micromolar lipopeptide. In addition, the lipopeptide increased expression of vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1). Similar results were obtained with 25 nM native OspA or lipidated recombinant OspA or OspB. Incubation of HUVEC with nonlipidated OspA peptide, nonlipidated recombinant OspA or OspB, or tripalmitoyl-S-glyceryl-cysteine had little or no effect on expression of these adhesion molecules. A mutant strain of B. burgdorferi that lacked OspA and OspB upregulated expression of E-selectin to the same degree as its wild-type counterpart, indicating that other spirochetal components also possess the ability to activate endothelium. Conditioned medium from HUVEC incubated with OspA lipopeptide or lipidated recombinant OspA induced chemotaxis of neutrophils in Boyden chamber assays, whereas the OspA preparations alone were devoid of chemotactic activity. When HUVEC grown on connective tissue substrates were treated with OspA lipopeptide, subsequently added neutrophils migrated across the endothelial monolayers. These results implicate the outer surface lipoproteins of B. burgdorferi as potential effector molecules in the promotion of a host inflammatory response.
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Affiliation(s)
- T J Sellati
- Department of Pathology, School of Medicine, State University of New York at Stony Brook 11794-8691, USA
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Rittig MG, Häupl T, Krause A, Kressel M, Groscurth P, Burmester GR. Borrelia burgdorferi-induced ultrastructural alterations in human phagocytes: a clue to pathogenicity? J Pathol 1994; 173:269-82. [PMID: 7931847 DOI: 10.1002/path.1711730311] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A chronic infection with the spirochaete Borrelia burgdorferi typically results in a multistage, multisystem illness. Thus, Lyme borreliosis may provide an interesting model to study the pathomechanisms of microbial persistence. In the present investigation, human peripheral blood monocytes, polymorphonuclear leukocytes, and synovial macrophages were incubated with B. burgdorferi and examined by light and electron microscopy. It was found that incubation with the spirochaetes induced distinct features in the phagocytes. Features which may be related to the pathogenesis of Lyme disease included the segmental uptake of spirochaetes with leaky lysosomes, the invagination of large membrane areas, the extra-lysosomal degradation of internalized B. burgdorferi cells and, finally, the formation of mononuclear syncytial cells and homotypic cell clusters. Features of unknown relevance were the occurrence of two types of cytoplasmic inclusion bodies and exocytic vesicles. These novel findings suggest that reactive alterations of the phagocytes may contribute to the pathogenesis of Lyme borreliosis, which could help to focus future histopathological studies. Moreover, these results may provide new insights into the pathogenesis of other infectious diseases characterized similarly by microbial persistence.
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Affiliation(s)
- M G Rittig
- Department of Anatomy I, University of Erlangen, Germany
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