Human B-blast specific target determinants in CML: a panel study.

The B blast specific target determinant phenotype defined by cytotoxic lymphocytes and the HLA-DR phenotype was tested for correlation in two panel studies. First, CTL reagents with B blast specificity were selected from CTLs educated between HLA-A, B, (C) identical unrelated donors giving no cytotoxicity with specific T blasts, resulting in free selection of panel B blasts used as targets. Second, CTLs educated between HLA non-identical unrelated donors giving cytotoxicity against specific T as well a B blast targets could be seen with negative reactions against T blasts but positive reactions against B blasts of selected panel members giving, in this set up, a free selection of donors cocultured for education of CTLs. These panel studies showed that HLA-DR associated B blast specific target determinants can be identified by CTLs, indicating that the HLA system codes for these determinants either through gene products of a locus closely linked to or identical with the HLA-DR locus.