Inhibition of adjuvant arthritis by protein antigens. I. Inhibitory capacities and dose relationships of different proteins.

The addition of 10 mg of ovalbumin (HEA), bovine γ-globulin (BGG) or rat γ-globulin (RGG) to a mycobacterial wax D adjuvant emulsion inoculated intracutaneously reduced the induction of adjuvant arthritis from a 95 per cent incidence in control rats to 18.5, 26.6 and 33 per cent, respectively. There was notably less protection from bovine plasma albumin, rat serum albumin or heat denatured rat serum albumin. With a 5-mg dose of HEA arthritis was reduced to 37.5 per cent. Lower dosages were not protective. Little or no protection resulted from pre-treatments with HEA or BGG intramuscularly, with BGG in incomplete adjuvant intracutaneously or from the latter given separately but concurrently with wax D adjuvant. The inhibitory effects of the various proteins may be attributed to their adsorption by wax D in vitro before inoculation. Alternatively the protein may compete as an immunogen with an immunogenic moiety of the wax D.