Induction of Tk polyagglutination by Bacteroides fragilis culture supernatants. Associated modifications of A B H and I i antigens.

Tk transformed red blood cells were obtained in vitro by treatment with supernatants from cultures of three different Bacteroides fragilis strains. The reactions of these cells with AB sera show that Tk is different from other known types of polyagglutination. Beside the already known modifications of A B H antigens, we found that Tk activated cells have an important modification of I and i antigens: both are reduced, and can even be completely destroyed.