The Production of Interleukin 2 as a Measure of Reactivity in Mixed Lymphocyte Culture

Interleukin 2 (IL2) produced in vitro in mixed lymphocyte cultures was measured by induction of growth in cells dependent on IL2 for proliferation. The amount of IL2 in early cultures (24 and 48 hours) clearly differentiated the degree of HLA-D locus identity between various individuals. Very low amounts of IL2 were produced in cultures between HLA-D identical subjects. The use of IL2 measurement offers a method in the early culture phase for predicting the T cell proliferation which is dependent on the presence of IL2.