[The use of proteases for enhancing the sensitivity of reactions to detect group isohemagglutinins in the forensic medical study of blood stains].

Group a and b isohemagglutinins are much better detected in blood stains by enzyme-treated, but not native red cells. This is specially true for antibodies of poorly dissolved strains, whose group antibodies can be detected virtually only by enzyme-treated red cells in papain extracts possessing the highest immunological activity. Two sensitive methods for the detection of isohemagglutinins have been developed: extract titration and modified Lattes' method, permitting a reliable detection of group antibodies in old blood stains, undetectable by routine methods.