Enzymes are particularly useful in detecting antibodies of the Rh system and offer a valuable addition to the range of serological techniques used for antibody identification, especially where it is suspected that there is a mixture of antibodies. Papain destroys certain blood group antigens, notably M, N, S, Fya, Fyb and Xga, a property that may be useful for identification and separation of mixed antibodies.

Enzymes may potentiate agglutination in at least two different ways: by reducing surface charge of red cells and by removing structures, which sterically interfere with the access of antibody molecules.

Lorne Papenzyme-Plus reagent is a ready to use liquid preparation of stabilised papain. The reagent is standardised by serological methods for use in blood group antibody investigations. The reagent is supplied at optimal dilution for use with all the recommended techniques stated below without need for further dilution or addition.