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Abstract
Lyme disease represents a growing public health threat. The controversial science and politics of Lyme disease have created barriers to reliable diagnosis and effective treatment of this protean illness. Two major clinical hurdles are the absence of a therapeutic end point in treating Borrelia burgdorferi, the spirochetal agent of Lyme disease, and the presence of tickborne coinfections with organisms such as Babesia, Anaplasma, Ehrlichia and Bartonella that may complicate the course of the disease. From a pathophysiologic standpoint, the affinity of Borrelia burgdorferi for multiple cell types and the presence of nonreplicating forms of the Lyme disease spirochete have contributed to persistent infection and failure of simple antibiotic regimens. Newer approaches to the treatment of Lyme disease should take into account its clinical complexity in coinfected patients and the possible need for prolonged combination therapy in patients with persistent symptoms of this potentially debilitating illness. The optimal antibiotic regimen for chronic Lyme disease remains to be determined.
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Affiliation(s)
- Raphael B Stricker
- California Pacific Medical Center , 450 Sutter Street, Suite 1504, San Francisco, CA 94108, USA.
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2
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Sen E, Sigal LH. Enhanced Adhesion and OspC Protein Synthesis of the Lyme Disease Spirochete Borrelia Burgdorferi Cultivated in a Host-Derived Tissue Co-Culture System. Balkan Med J 2013; 30:215-24. [PMID: 25207103 DOI: 10.5152/balkanmedj.2013.7059] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 12/06/2012] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND The adhesion process of Borrelia burgdorferi to susceptible host cell has not yet been completely understood regarding the function of OspA, OspB and OspC proteins and a conflict exists in the infection process. AIMS The adhesion rates of pathogenic (low BSK medium passaged or susceptible rat joint tissue co-cultivated) or non-pathogenic Borrelia burgdorferi (high BSK medium passaged) isolate (FNJ) to human umbilical vein endothelial cells (HUVEC) cultured on coverslips and the synthesis of OspA and OspC proteins were investigated to analyze the infection process of this bacterium. STUDY DESIGN In-vitro study. METHODS Spirochetes were cultured in BSK medium or in a LEW/N rat tibiotarsal joint tissue feeder layer supported co-culture system using ESG co-culture medium and labelled with 3H-adenine for 48 hours. SDS-PAGE, Western Blotting, Immunogold A labeling as well as radiolabeling experiments were used to compare pathogenic or non pathogenic spirochetes during the adhesion process. RESULTS Tissue co-cultured B. burgdorferi adhered about ten times faster than BSK-grown spirochetes. Trypsin inhibited attachment to HUVEC and co-culture of trypsinized spirochetes with tissues reversed the inhibition. Also, the synthesis of OspC protein by spirochetes was increased in abundance after tissue co-cultures, as determined by SDS-PAGE and by electron microscopy analysis of protein A-immunogold staining by anti-OspC antibodies. OspA protein was synthesized in similar quantities in all Borrelia cultures analyzed by the same techniques. CONCLUSION Low BSK passaged or tissue co-cultured pathogenic Lyme disease spirochetes adhere to HUVEC faster than non-pathogenic high BSK passaged forms of this bacterium. Spirochetes synthesized OspC protein during host tissue-associated growth. However, we did not observe a reduction of OspA synthesis during host tissue co-cultivation in vitro.
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Affiliation(s)
- Ece Sen
- Department of Basic and Industrial Microbiology, Trakya University Faculty of Science, Edirne, Turkey
| | - Leonard H Sigal
- Department of Internal Medicine Rheumatology, University of Medicine and Dentistry of New Jersey, New Brunswick, USA
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3
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Stricker RB. Counterpoint: long-term antibiotic therapy improves persistent symptoms associated with lyme disease. Clin Infect Dis 2007; 45:149-57. [PMID: 17578772 DOI: 10.1086/518853] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Accepted: 02/21/2007] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Controversy exists regarding the diagnosis and treatment of Lyme disease. Patients with persistent symptoms after standard (2-4-week) antibiotic therapy for this tickborne illness have been denied further antibiotic treatment as a result of the perception that long-term infection with the Lyme spirochete, Borrelia burgdorferi, and associated tickborne pathogens is rare or nonexistent. METHODS I review the pathophysiology of B. burgdorferi infection and the peer-reviewed literature on diagnostic Lyme disease testing, standard treatment results, and coinfection with tickborne agents, such as Babesia, Anaplasma, Ehrlichia, and Bartonella species. I also examine uncontrolled and controlled trials of prolonged antibiotic therapy in patients with persistent symptoms of Lyme disease. RESULTS The complex "stealth" pathology of B. burgdorferi allows the spirochete to invade diverse tissues, elude the immune response, and establish long-term infection. Commercial testing for Lyme disease is highly specific but relatively insensitive, especially during the later stages of disease. Numerous studies have documented the failure of standard antibiotic therapy in patients with Lyme disease. Previous uncontrolled trials and recent placebo-controlled trials suggest that prolonged antibiotic therapy (duration, >4 weeks) may be beneficial for patients with persistent Lyme disease symptoms. Tickborne coinfections may increase the severity and duration of infection with B. burgdorferi. CONCLUSIONS Prolonged antibiotic therapy may be useful and justifiable in patients with persistent symptoms of Lyme disease and coinfection with tickborne agents.
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Stricker RB, Lautin A, Burrascano JJ. Lyme disease: the quest for magic bullets. Chemotherapy 2006; 52:53-9. [PMID: 16498239 DOI: 10.1159/000091726] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2004] [Accepted: 06/20/2005] [Indexed: 01/20/2023]
Abstract
Lyme disease represents a growing public health threat. Recent molecular and genetic studies have confirmed that Borrelia burgdorferi, the spirochetal agent of Lyme disease, is one of the most complex bacteria known to man. Affinity for multiple cell types and the presence of non-replicating forms of B. burgdorferi have contributed to persistent infection and failure of simple antibiotic regimens. The controversial clinical science of Lyme disease has impeded reliable diagnosis and effective treatment of this protean illness. Two major clinical hurdles are the absence of a therapeutic endpoint in treating Lyme disease and the presence of tick-borne coinfections that may complicate the course of the illness. New strategies for the diagnosis, treatment and prevention of Lyme disease are urgently needed.
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5
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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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6
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Abstract
Lyme disease represents a public health threat of major proportions. The murky science and acrimonious politics of Lyme disease have created barriers to reliable diagnosis and effective treatment of this protean illness. Two major clinical problems with the disease are the absence of a therapeutic end point in treating Borrelia burgdorferi, the spirochetal agent of Lyme disease, and the presence of tick-borne co-infections, such as babesiosis, anaplasmosis and bartonellosis, that may complicate the course of the illness. From a pathophysiological standpoint, the affinity of B. burgdorferi for multiple cell types and the presence of non-replicating forms of the spirochete have contributed to persistent infection and failure of simple antibiotic regimens. Newer approaches to the treatment of Lyme disease should take into account its clinical complexity in co-infected patients and the possible need for prolonged combination therapy in patients with persistent symptoms of this potentially debilitating illness. The risk and prevention of human transmission of Lyme disease merit further study.
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Affiliation(s)
- Raphael B Stricker
- Department of Medicine, California Pacific Medical Center, 450 Sutter Street, Suite 1504, San Francisco, CA, USA.
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Suhonen J, Komi J, Soukka J, Lassila O, Viljanen MK. Interaction between Borrelia burgdorferi and immature human dendritic cells. Scand J Immunol 2003; 58:67-75. [PMID: 12828560 DOI: 10.1046/j.1365-3083.2003.01284.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Antigen uptake and the following maturation of dendritic cells (DCs) are pivotal to the initiation of specific antimicrobial immune responses. DCs also play an important role in the recruitment and activation of the cells of the innate immune system. We have examined the interactions of DCs with Borrelia burgdorferi to find explanations for the difficulties the human immune system has in dealing with the bacterium. Phagocytosis of B. burgdorferi by immature DCs and the effect of the bacterium on the maturation and interleukin-8 (IL-8) secretion of DCs were studied. Borreliae were phagocytized and processed into fragments by DCs; narrow tube-like pseudopods and broad pseudopods were used for the engulfment. The immature DC population gained a heterogeneous appearance within 2 h of incubation with the borreliae. A 24 h coculture with borreliae induced maturation and IL-8 secretion in the DCs in a manner comparable with the effect of lipopolysaccharides. All strains studied, including a mutant strain lacking outer surface proteins A and B, were capable of inducing these responses. Thus, our results did not show any clear inadequacy concerning the way DCs are dealing with B. burgdorferi. However, further studies on the subject are required.
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Affiliation(s)
- J Suhonen
- Department of Medical Microbiology, Laboratory of Biophysics, Institute of Biomedicine, Turku University, Turku, Finland.
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Rathinavelu S, de Silva AM. Purification and characterization of Borrelia burgdorferi from feeding nymphal ticks (Ixodes scapularis). Infect Immun 2001; 69:3536-41. [PMID: 11349010 PMCID: PMC98328 DOI: 10.1128/iai.69.6.3536-3541.2001] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Here we describe a protocol for purifying Borrelia burgdorferi from feeding ticks by velocity centrifugation and Percoll density gradient centrifugation. The purified spirochetes were motile and 10- to 20-fold purer than the bacteria in crude tick homogenates. The purified bacteria were present in sufficient quantity for protein and gene expression studies. In comparison to culture-grown bacteria, tick-borne spirochetes had several proteins that were upregulated and a few that were downregulated. When the levels of B. burgdorferi outer surface proteins OspA and OspC were measured, OspC protein and mRNA levels were lower in cultured bacteria than in bacteria purified from ticks. Although differences in OspA mRNA levels were observed between cultured and tick-borne bacteria, no differences were observed at the protein level. These experiments demonstrate that tick-transmitted borreliae display a gene expression and antigen profile different from that of spirochetes cultured in vitro.
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Affiliation(s)
- S Rathinavelu
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill 27599, USA
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Kuo MM, Lane RS, Giclas PC. A comparative study of mammalian and reptilian alternative pathway of complement-mediated killing of the Lyme disease spirochete (Borrelia burgdorferi). J Parasitol 2000; 86:1223-8. [PMID: 11191895 DOI: 10.1645/0022-3395(2000)086[1223:acsoma]2.0.co;2] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The potential bactericidal activity of the alternative complement pathway of mammalian and reptilian sera to Borrelia burgdorferi sensu stricto (s.s.) was evaluated in vitro. Complement-mediated killing was observed when cultured spirochetes were inoculated into sera from the western fence lizard (Sceloporus occidentalis) and from the southern alligator lizard (Elgaria multicarinata), but not when they were inoculated into serum from either the deer mouse (Peromyscus maniculatus) or from humans. Spirochetes were still alive after 4 hr in lizard serum that had been preheated at 56 C for 30 min to inactivate complement. Furthermore, when lizard serum was chelated with 10 mM ethylenediaminetetraacetic acid to block all complement activation, borreliacidal activity was arrested. When lizard serum was chelated with 10 mM ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid plus 4 mM MgCl2 to block only classical complement pathway activation, >85% of spirochetes were immobilized within 1 hr. Differences in B. burgdorferi s.s. mortality were not observed when chelators with or without MgCl2 were added to serum from either deer mice or humans. Proteins comprising the alternative complement pathway are responsible for the borreliacidal activity observed in the blood of S. occidentalis and E. multicarinata.
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Affiliation(s)
- M M Kuo
- Department of Environmental Science, Policy and Management, University of California, Berkeley 94720, USA
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Fenno JC, Tamura M, Hannam PM, Wong GW, Chan RA, McBride BC. Identification of a Treponema denticola OppA homologue that binds host proteins present in the subgingival environment. Infect Immun 2000; 68:1884-92. [PMID: 10722578 PMCID: PMC97362 DOI: 10.1128/iai.68.4.1884-1892.2000] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Proteins secreted or exported by Treponema denticola have been implicated as mediators of specific interactions between the spirochete and subgingival tissues in periodontal diseases. However, limited information is available on the ability of this peptidolytic organism to bind or transport soluble peptides present in the subgingival environment. A prominent 70-kDa protein was isolated from surface extracts of T. denticola ATCC 35405. A clone expressing a portion of the protein was identified in an Escherichia coli expression library of T. denticola DNA. DNA sequence analysis showed that the cloned gene encoded a peptide homologous to OppA, the solute binding protein of an ATP-binding cassette-type peptide transporter involved in peptide uptake and environmental signaling in a wide range of bacteria. Genes encoding OppB, -C, -D, and -F were identified directly downstream of oppA in T. denticola. OppA was present in representative strains of T. denticola and in Treponema vincentii but was not detected in Treponema pectinovorum or Treponema socranskii. Immunogold electron microscopy suggested that OppA was accessible to proteins at the surface of the spirochete. Native OppA bound soluble plasminogen and fibronectin but did not bind to immobilized substrates or epithelial cells. A T. denticola oppA mutant bound reduced amounts of soluble plasminogen, and plasminogen binding to the parent strain was inhibited by the lysine analog epsilon-aminocaproic acid. Binding of soluble host proteins by OppA may be important both for spirochete-host interactions in the subgingival environment and for uptake of peptide nutrients.
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Affiliation(s)
- J C Fenno
- Department of Microbiology, University of British Columbia, Vancouver, Canada.
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Probert WS, Johnson BJ. Identification of a 47 kDa fibronectin-binding protein expressed by Borrelia burgdorferi isolate B31. Mol Microbiol 1998; 30:1003-15. [PMID: 9988477 DOI: 10.1046/j.1365-2958.1998.01127.x] [Citation(s) in RCA: 205] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The attachment of pathogenic microorganisms to host cells and tissues is often mediated through the expression of surface receptors recognizing components of the extracellular matrix (ECM). Here, we investigate the ability of Borrelia spirochaetes to bind the ECM constituent, fibronectin. Borrelia lysates were separated by SDS-PAGE, transferred to nitrocellulose and probed with alkaline phosphatase-labelled fibronectin (fibronectin-AP). Five of six Borrelia species and four of eight B. burgdorferi sensu lato isolates expressed one or more fibronectin-binding proteins. Borrelia burgdorferi isolate B31 expressed a 47 kDa (P47) fibronectin-binding protein that was localized to the outer envelope based on susceptibility to proteinase K. The interaction of P47 with fibronectin was specific, and the region of fibronectin bound by P47 mapped to the gelatin/collagen binding domain. P47 was purified by affinity chromatography, digested with endoproteinase Lys-C, and the peptide fragments analysed by liquid chromatography/tandem mass spectroscopy. A search of protein databases disclosed that the P47 peptide mass profile matched that predicted for the bbk32 gene product of B. burgdorferi isolate B31. The bbk32 gene was cloned into Escherichia coli, and the ability of recombinant BBK32 to bind fibronectin and inhibit the attachment of B. burgdorferi was demonstrated. The identification of BBK32 as a receptor for fibronectin binding may enhance our understanding of the pathogenesis and chronic nature of Lyme disease.
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Affiliation(s)
- W S Probert
- Division of Vector-Borne Infectious Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, CO 80522, USA
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Grab DJ, Givens C, Kennedy R. Fibronectin-binding activity in Borrelia burgdorferi1. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1407:135-45. [PMID: 9685613 DOI: 10.1016/s0925-4439(98)00038-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Recently, the term MSCRAMM (microbial surface components recognizing adhesive matrix molecules), has been introduced to describe microbial molecules that recognize extracellular matrix (ECM) [1]. Here we present evidence for the presence of fibronectin-binding molecules in Borrelia burgdorferi and several other Borrelia species. Immunofluorescence studies show that plasma fibronectin is bound uniformly over the cell surface of free swimming B. burgdorferi. In addition, the spirochetes are able to bind to plasma fibronectin-coated microwell plates, an interaction that is inhibited by anti-fibronectin antibody as well as exogenous plasma fibronectin. Taken together, the data suggest that fibronectin binds to the surface of the spirochete. On Western blot-like assays, B. burgdorferi and some B. afzelii strains express a major fibronectin-binding protein (Fn-BA) with an approximate molecular mass of 52 kDa. In addition, several other major Fn-BAs were found in B. hermsii (26, 31, 33, 39, 46, 54 and 58 kDa) and B. turicatae (39, 41, 45, 50, 56, 59 and 66 kDa). Preliminary evidence suggests that fibronectin (and Fn-BA) may play a role as a molecular bridge between the spirochete and other components of the extracellular matrix.
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Affiliation(s)
- D J Grab
- Department of Parasitology, Tulane Regional Primate Research Center, Covington, LA, USA.
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Sigal L. Lyme borreliosis (Lyme disease): interactions of Borrelia burgdorferi sensu lato with human (and other mammalian) hosts. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0020-2452(98)80013-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Brorson O, Brorson SH. In vitro conversion of Borrelia burgdorferi to cystic forms in spinal fluid, and transformation to mobile spirochetes by incubation in BSK-H medium. Infection 1998; 26:144-50. [PMID: 9646104 DOI: 10.1007/bf02771839] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The purpose of this study was to examine the structural alterations of Borrelia burgdorferi when exposed to spinal fluid. Normal, mobile spirochetes were inoculated into spinal fluid, and the spirochetes were converted to cysts (spheroplast L-forms) after 1-24 h. When these cystic forms were transferred to a rich BSK-H medium, the cysts were converted back to normal, mobile spirochetes after incubation for 9 to 17 days. The cultures were examined by dark field microscopy (DFM), interference contrast microscopy (ICM) and transmission electron microscopy (TEM). When neuroborreliosis is suspected, it is necessary to realize that B. burgdorferi can be present in a cystic form, and these cysts have to be recognized by microscopy. This study may also explain why cultivation of spinal fluid often is negative with respect to B. burgdorferi.
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Affiliation(s)
- O Brorson
- Dept. of Microbiology, Vestfold Sentralsykehus, Tønsberg
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15
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Abstract
The immunopathogenesis of Lyme disease is complicated and requires a thorough understanding of the interaction among the causative organism, Borrelia burgdorferi, its tick vector, and its mammalian hosts. In vitro, animal and human studies have shown that the organism is capable of adapting to and utilizing elements from its environment to establish infection and persist despite a inducing a strong immune response. Indeed, the immune response may be responsible for many of the symptoms associated with Lyme disease. It appears that humoral immunity plays the greatest role in clearance of the organism. Cytokines released by Th 1 or Th 2 subsets of CD4+ cells have been shown to play an important role in determining outcome of the disease in animal models possibly through their effects on immunoglobulin class switching. In the small percentage of patients who have treatment resistant chronic Lyme disease, autoimmune mechanisms may play a role in persistent disease.
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Affiliation(s)
- L T Hu
- Tupper Research Institute, Division of Geographic Medicine and Infectious Diseases, New England Medical Center, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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Sun Q, Smith GM, Zahradka C, McGavin MJ. Identification of D motif epitopes in Staphylococcus aureus fibronectin-binding protein for the production of antibody inhibitors of fibronectin binding. Infect Immun 1997; 65:537-43. [PMID: 9009310 PMCID: PMC176093 DOI: 10.1128/iai.65.2.537-543.1997] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
A fibronectin-binding protein (FnBP) adhesin of Staphylococcus aureus possesses three 37- or 38-amino-acid motifs (D1, D2, and D3) that can each bind fibronectin (Fn) with low affinity and that in tandem comprise D1-3, a high-affinity Fn-binding domain. To identify epitopes for the generation of adhesion-blocking antibodies, rabbits were immunized with recombinant D1-3 or with a glutathione S-transferase fusion protein, GSTD1-3. Affinity-purified antibodies from the D1-3 immunization were poor inhibitors of Fn binding to S. aureus and recognized several different epitopes, with a preference for clusters of acidic amino acids that do not contribute to Fn binding. Antibodies generated with GSTD1-3 as an immunogen were more effective inhibitors, but concentrations in excess of 20 microg x ml-1 did not promote more than 50% inhibition. These antibodies were highly specific for amino acids 21 to 34 of D1 (D1(21-34)), which contain a sequence that is essential for Fn binding and are identical to D2 at 12 of 14 residues. Neither antibody preparation recognized D3(20-33) of the D3 motif, where the only homology to D1(21-34) and D2(21-34) comprises a sequence motif, GG(X3,4)(I/V)DF, that is critical to Fn binding. However, antibodies specific for both D1(21-34) and D3(20-33) could be obtained by using synthetic peptides corresponding to these sequences as immunogens. F(ab')2 fragments derived from these antibodies each caused 40 to 50% inhibition of Fn binding to S. aureus, and their ability to bind to purified FnBP was eliminated by competing Fn. However, mixtures of the two F(ab')2 preparations did not provide additive or synergistic inhibition of Fn binding. Therefore, inhibition of Fn binding to S. aureus requires antibodies specific for D1(21-34) and D3(20-33), but a mixture of antibodies specific for both sequences did not provide complete inhibition.
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Affiliation(s)
- Q Sun
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Canada
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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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