A small allelic variant in donor class I MHC is sufficient to induce alloantibodies following transfusion of standard or pathogen-reduced platelets in mice.

Minor allelic variants in both the class I and class II MHC are capable of inducing an alloresponse to transfusion. The Kbm1 PRP induced alloantibodies even with pathogen reduction and did not show signs of inducing the partial tolerance to subsequent transfusions observed with a larger MHC mismatch.