The Functional Heterogeneity of HLA Class II Determinants

Abstract

The original discovery by Navarrete et al. (1) that HLA-DQ and HLA-DR specificities are differentially expressed on leukemic cells and particularly that HLA-DQ is absent from acute myeloid leukemic cells, led us to investigate whether HLA-DQ has a specific unique role in the immune response. If so, the absence of HLA-DQ on the tumor cells may be advantageous for the development of leukemia. This concept was supported by the experiments of Corte et al. (2), which showed that HLA-DQ antibody was able to prevent the in vitro generation of cytotoxic T cells. These findings were subsequently confirmed in our laboratory (3). Previous genetic experiments in the mouse in which recombinant congenic mouse strains were employed also suggested that H-2 E (the functional counterpart of HLA-DQ) is important in the generation of cytotoxic T cells.