Experimental cryoglobulinaemia: Production and properties of streptococcus-induced rabbit cryoglobulins

Cryoglobulin production in rabbits immunized with streptococcal vaccines began about 3 weeks after immunization began and maximum yields from fresh immune sera ranged from <0.1 mg/ml to >6 mg/ml in individual rabbits. The cryoglobulins contained IgM and IgG, antiglobulin that was mainly IgM, IgG homogeneous antibodies to streptococci, and DNA. It is postulated that cryoglobulins are formed in two stages: alteration of IgG followed by antigen—antibody precipitation with antiglobulin.