Collagen cross-reactive antigen of Sarcocystis cruzi

Collagen cross-reactive antigenic substance(s) in Sarcocystis cruzi cysts were examined with immunologic techniques using anti-bovine collagen type-specific, but non-species-specific, antibodies. By immunoperoxidase test, anti-bovine collagen type-specific, but non-species-specific, antibodies. By immunoperoxidase test, anti-bovine type IV collagen antibody showed higher reactivity 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 extract, which exhibited specific reactivity to anti-bovine type IV collagen antibody, was detected. The band had a molecular weight of approximately 66 kDa. These results suggest that sarcocysts of S. cruzi may be comprised of bovine collagen type IV cross-reactive antigenic substances.