HIGH-AFFINITY CYTOTOXIC T-LYMPHOCYTES AFTER NON-HLA-SHARING BLOOD-TRANSFUSION - THE OTHER SIDE OF THE COIN

Previously, we have shown that pretransplantation blood transfusion mo dulates the T cell repertoire to a great extent. Patients receiving a BT from a donor sharing one HLA haplotype with the patient (HLA-sharin g BT) develop CTE nonresponsiveness against cells of the BT donor and show a selective decrease in the usage of T cell receptor V beta famil ies. The present study has focused on the analysis of the T cell reper toire in patients receiving an HLA mismatched (non-HLA-sharing) BT. CT L precursor frequencies were measured against single class I-mismatche d antigens in split-well analysis. In addition, blocking studies of CT L-target cell interaction were performed with anti-CD8 monoclonal anti bodies. The results demonstrate that non-HLA sharing ET immunizes and induces the generation of CD8 independent, high-affinity CTL against i mmunogenic class I-mismatched antigens. Such HLA class I antigens migh t become nonacceptable mismatches in subsequent organ transplantation.