LD typing and the lack of involvement of SD antigens in the priming process.

Peripheral blood lymphocytes with known HLA-SD were typed for LD determinants using a panel of primed cells prepared from SD identical lymphocytes. Then these lymphocytes (with known SD and LD) were primed by x-irradiated cells from the same SD and LD group and their secondary reactions were evaluated. Disparity in SD antigens of responder and stimulator cells did not produce primed cells and lymphocytes were primed only for LD differences. This finding allows LD typing using primed cells from a panel of randomly selected lymphocytes regardless of their HLA-SD.