Class II alloantigen expression on leukemic cells

: Class II antigen expression on leukemic cells has been mainly studied using monoclonal antibodies (Mabs). On the other hand, class II polymorphism has been mainly studied using alloantisera. The present study shows that the reactivity of leukemic cells from different lineages with class II Mabs was not always the same as that obtained with alloantisera and that the reactivity varied depending on the leukemic cell-type studied.