Heat-labile IgG2a antibodies affect cure of Trypanosoma musculi infection in C57BL/6 mice.
Immune plasma (IP) obtained from mice cured of Trypanosoma musculi infection is able to mediate trypanosome clearance both in vivo and in vitro. A protein A-derived immunoglobulin fraction of IP containing primarily IgG2a and IgG3 shares this curative activity. Additional purification of IP with the use of anti-IgG2a and anti-IgG3 coupled to Sepharose beads demonstrates that the curative activity of IP resides solely in the IgG2a fraction; IP depleted of IgG2a is no longer able to effect T. musculi removal. Furthermore, this curative IgG2a is labile to heat treatment for 30 min at 56 degrees C. Enzyme-linked immunosorbent assays show that trypanosome-specific IgG2a builds up gradually over the course of infection, and temporarily drops slightly at the time of parasite clearance.
D000818:Animals; D006358:Hot Temperature; D007074:Immunoglobulin G / Q000276:immunology*; D007132:Immunoglobulin Isotypes; D051379:Mice; D008810:Mice, Inbred C57BL / Q000276:immunology; D013997:Time Factors; D014345:Trypanosoma / Q000276:immunology*; D014352:Trypanosomiasis / Q000276:immunology*
D007074:Immunoglobulin G; D007132:Immunoglobulin Isotypes