Human B‐Blast Specific Target Determinants in CML:

Abstract

The B [bone marrow-derived] blast specific target determinant phenotype defined by cytotoxic lymphocytes and the HLA-DR phenotype was tested for correlation in 2 panel studies. CTL [cytotoxic thymus-derived lymphocyte] reagents with B blast specificity were selected from CTL 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. CTL educated between HLA non-identical unrelated donors giving cytotoxicity against specific T as well as B blast targets were 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 CTL. HLA-DR associated B blast specific target determinants can be identified by CTL, indicating that the HLA system codes for these determinants through gene products of a locus were closely linked to or identical with the HLA-DR locus.