Use of the enzyme method for antibody identification

Enzyme methods for red blood cell antibody testing may have two goals: detection of weak antibodies by increasing the strength of the reactions and differentiation of the antibodies in an antibody mixture by abolishing the reaction of antibodies against enzyme-labile antigens. We analyzed the phenotype listing sheets of all lots of one year (expiration date in 2002) of 8 products (5 manufacturers) (together 130 worksheets). The aim was to find out how often some antibodies could only be detected after enzyme treatment, when there is an additional antibody against one of the following enzyme-labile antigens in the patient's serum: Fya, Fyb, M, N, S and s. If there is one of these antibodies against an enzyme-labile antigen, an additional antibody against one of the following enzyme-stable antigens D, C, E, c, e, CW, K, Kpa, Jsa, Jka, Jkb, Lea, Leb, P1, Lua cannot be detected on average in 20% of the panels. Moreover, in a further 37% of the panels there is no red blood cell suspension carrying the Kpa, in 44% none carrying the Jsa and in 19% no one carrying the Lua antigen. On the other hand, an antibody against one of the high-incidence antigens k, Kpb, Jsb or Lub can be detected in each of the 130 panels, also if there is an additional antibody directed against one of the above-mentioned enzyme-labile antigens. As also nowadays in some antibody identification panels antibodies against some enzyme-stable antigens might be covered by antibodies against enzyme-labile antigens, the enzyme method can be a helpful completion in antibody differentiation in some sera with multiple antibodies.