Clonal distribution of HLA-restricted antigen-reactive T cells in man.

The [3H]thymidine suicide technique was used to test the hypothesis that the response of immune human T cells from HLA-D/DR heterozygous donors to the soluble protein antigen purified protein derivative (PPD) is clonally expressed and consists of the concurrent proliferation of at least two separable subpopulations of lymphocytes. The results showed that each of the two subpopulations react to one or the other of the HLA-D/DR antigens presented together with PPD by allogeneic monocytes. In addition, using in vitro priming techniques of in vivo sensitized lymphocytes from heterozygous donors, it was possible to generate specific memory cells capable of recognizing the priming soluble protein antigen together with the HLA-D/DR determinant present in the initial sensitizing culture.