COLLAGEN CROSS-REACTIVE ANTIGEN OF SARCOCYSTIS-CRUZI

Collagen cross-reactive antigenic substance(s) in Sarcocystis cruzi cy sts were examined with immunologic techniques using anti-bovine collag en type-specific, but non-species-specific, antibodies, By immunoperox idase test, anti-bovine type IV collagen antibody showed higher reacti vity to the cysts than other antibodies tested. Cyst wall rupture was induced by collagenase treatment and digestion was inhibited with EDTA supplementation. With immunoblotting analysis, one band of the cyst e xtract, which exhibited specific reactivity to anti-bovine type IV col lagen antibody, was detected. The band had a molecular weight of appro ximately 66 kDa. These results suggest that sarcocysts of S. cruzi may be comprised of bovine collagen type IV cross-reactive antigenic subs tances.