PROTECTIVE ACTIVITY OF BORRELIA DUTTONII-SPECIFIC IMMUNOGLOBULIN SUBCLASSES IN MICE

To analyse the immune response of mice to Borrelia duttonii infection, BALB/c mice were inoculated intraperitoneally with B. duttonii strain 406K, and the titres of B. duttonii-specific immunoglobulins - IgM, I gG1, IgG2a, IgG2b and IgG3 - were determined by ELISA, IgM antibodies appeared first, followed by IgG2a and IgG3, and then IgG1 and IgG2b, T he protective activity of individual classes and subclasses of B. dutt onii-specific immunoglobulins was then determined by passive immunisat ion of BALB/c mice,vith immunoglobulin preparations purified by affini ty chromatography. The mice were then challenged by intraperitoneal in oculation of B. duttonii, The study demonstrated that B. duttonii-spec ific IgM and IgG3 protected against the development of spirochaetaemia and death after borrelial infection, whereas B. duttonii-specific IgG 1, IgG2a and IgG2b had low protective activities.