Open AccessCirculating immune complexes in experimental syphilis and their relation to immunological response against Treponema pallidum
Author(s) -
Podwińska Jadwiga
Publication year - 1991
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1991.tb04201.x
Subject(s) - treponema , syphilis , immune system , antibody , immunology , biology , immunoglobulin g , virology , human immunodeficiency virus (hiv)
Summary It was found that circulating immune complexes (CIC) were formed in rabbits at different times after infection with Treponema pallidum . The CIC which appeared at the beginning of the disease were short‐lived (2–6 weeks) but those appearing later than 20 weeks after infection remained for 10–25 weeks. CIC contained both IgM and IgG classes of immunoglobulin. The antibodies present in CIC were found to be specific and nonspecific for T. pallidum . The presence of CIC led to a marked decline of treponemal antibodies in rabbit sera. The cell‐mediated immune response measured by the macrophage migration inhibition (MMI) test at the beginning of the disease (up to 12 weeks) was not decreased. However, when syphilis lasted for more than 14 weeks and when CIC were formed mainly from IgG, a distinct decrease in the ability of lymphocytes to cause MMI was observed. These findings strongly suggest that IgG‐complexes suppress the immunological responsiveness of lymphocytes against T. pallidum which in turn facilitates the multiplication of treponemes in the host.