HUMAN CORD-BLOOD CONTAINS AN IGM ANTIBODY TO THE 41KD FLAGELLAR ANTIGEN OF BORRELIA-BURGDORFERI

Natural antibodies are the IgM products of fetal and neonatal B cells. These are germline encoded low affinity antibodies with multiple spec ificities to self and exogenous antigens. Lyme borreliosis is the dise ase resulting from infection with the spirochete, Borrelia burgdorferi . The humoral response to this organism is brisk, directed at multiple proteins, and persistant. Antibody to the 41kd flagellar antigen is f ound early in disease, but may also be found in non-exposed individual s. These properties suggest that the anti-41kd antibody may be a natur al antibody. We report here the finding of an IgM anti-41kd reactivity in 29% of cord blood samples from patients in an area non-endemic for Lyme disease. The results are consistent with the hypothesis that ant ibody to flagellin may be a germline encoded natural antibody, and cou ld be important in the immunopathogenesis of Lyme arthritis and other arthritides.