A New Determinant, Defined by PLT, Coded for in the HLA Region and Apparently Independent of the HLA‐D and DR Loci

Abstract
A PLT [primed lymphocyte testing-derived] cell was raised between a responder cell which carried the HLA-D and HLA-DR specificities Dw3, Dw8; DRw3; DRw8 and a stimulator cell which was most likely homozygous for HLA-Dw3, DRw3. The PLT cell appeared to recognize a determinant (PL3A) which was different from the officially recognized HLA-D and DR determinants, associated with HLA-A1, B8, Dw3 and DRw3 and segregated in 3 informative families with HLA. Another responder-stimulator combination could be selected to raise PLT cells which recognized the same determinant.