title: Pathogenesis of Yersinia-triggered reactive arthritis: immunological, microbiological and clinical aspects.
abstract: When a patient develops reactive arthritis after Yersinia enteritis, the following conditions are often fulfilled: the patient is HLA-B27-positive; however, some B27-negative individuals develop severe arthritis and some positives do not, in the initial phase, the diarrhea is milder, the anti-Yersinia antibody response of IgG class is more vigorous and persists longer, the anti-Yersinia antibody response of IgA class is more vigorous and persists much longer, the anti-Yersinia antibodies of IgA1 and IgA2 subclass, those with J-chain and, especially, those with secretory piece are produced more vigorously, indicating local immunostimulation close to the intestinal epithelium, in the early phase, Yersinia-IgM immune complexes are found in the circulation, and the lymphocyte transformation response against not only Yersinia but also against other gram-negative enteric bacteria is weaker. When all these aspects are considered together a strong suspicion arises that the patients who are destined to develop reactive arthritis fail in their first line of defense against the invading organism when contracting a Yersinia enteritis. This may lead to persistence of the microorganism within the body, e.g., in the intestinal epithelium or in the mesenteric lymphoid tissues, maintaining a stimulus for a prolonged--apparently futile and perhaps harmful--antibody production. Finally, the initiating and decisive factor should not be forgotten: the Yersinia. Why and how it triggers the process is at present one of the enigmas of the pathogenesis of reactive arthritis.
mesh_terms: D000907:Antibodies, Bacterial / Q000096:biosynthesis; D000917:Antibody Formation; D000918:Antibody Specificity; D000936:Antigen-Antibody Complex; D000942:Antigens, Bacterial / Q000276:immunology; D001168:Arthritis / Q000209:etiology* / Q000276:immunology / Q000382:microbiology; D003429:Cross Reactions; D004751:Enteritis / Q000150:complications* / Q000276:immunology / Q000382:microbiology; D006680:HLA Antigens / Q000276:immunology; D015796:HLA-B27 Antigen; D006801:Humans; D007111:Immunity, Cellular; D007070:Immunoglobulin A / Q000096:biosynthesis; D007071:Immunoglobulin A, Secretory / Q000096:biosynthesis; D007074:Immunoglobulin G / Q000096:biosynthesis; D007144:Immunoglobulin J-Chains / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000096:biosynthesis; D007711:Klebsiella pneumoniae / Q000276:immunology; D008213:Lymphocyte Activation; D008970:Molecular Weight; D012703:Serotyping; D013601:T-Lymphocytes / Q000276:immunology; D015009:Yersinia Infections / Q000150:complications* / Q000276:immunology; D015008:Yersinia enterocolitica / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D000936:Antigen-Antibody Complex; D000942:Antigens, Bacterial; D006680:HLA Antigens; D015796:HLA-B27 Antigen; D007070:Immunoglobulin A; D007071:Immunoglobulin A, Secretory; D007074:Immunoglobulin G; D007144:Immunoglobulin J-Chains; D007075:Immunoglobulin M