HLA‐D Region Products Are Expressed in Endothelial Cells Detection by Primed Lymphocyte Typing

Abstract

The mixed lymphocyte endothelial cell culture was studied by the primed lymphocyte typing (PLT) technique. By comparing the HLA-D/DR specificity of the secondary response when using either peripheral blood mononuclear cells (PBM) or endothelial cells from umbilical cords for priming or restimulation of lymphocytes, it was found that PBM from newborns would induce a clear-cut specificity for HLA-DIDR when used for priming as well as for restimulation. N o HLA-DIDR specificity was seen, however, when endothelial cells were used for restimulation of lymphocytes primed to HLA-DIDR on PBM. On the other hand, lymphocytes primed to endothelial cells showed significant, albeit not very strong specificity for HLA-D/DR when restimulated with PBM. Our experiments suggest that HLA-D region products are present on endothelial cells, and thus confirm and extend serological studies using anti DR antisera.

HLA‐A, B, C; ‐DR; ‐MT, ‐MB, and SB antigens on unstimulated human endothelial cells

“…Expression of class I and class I1 MHC antigens on the endothelium might be therefore important in determining the immunogenicity of the transplanted organs. Attempts to use endothelial cells of umbilical cord origin have yielded inconclusive results, especially in regard to the expression of class I1 histocompatibility antigens (Hirschberg et al 1979, Moen et al 1980, Pober et al 1983). Experiments were therefore performed to investigate the expression of HLA-DR and other class I1 MHC antigens on endothelial cells in comparison with monocytes, B and T lymphocytes isolated from the same source, the umbilical cord.…”