USEFULNESS OF FREQUENCY-ANALYSIS OF CYTOTOXIC T-LYMPHOCYTES PRECURSORS (CTL-P) FOR SELECTION OF HLA MATCHED UNRELATED MARROW DONORS

A child with Sanfilippo syndrome and 5 potential unrelated marrow dono rs were typed serologically, tested in mixed lymphocyte reaction and t yped by restriction fragment length polymorphism analysis in attempt t o find a suitable donor. All donors were found to be identical with th e recipient, however these studies were not conclusive in identifying the best match donor. Therefore, recipient-donor pairs were examined b y HLA-DR oligotyping. In addition we have studied the potential of cyt otoxic T-lymphocytes precursors (CTL-p) analysis as a means of selecti on for matched unrelated donors, Low frequencies (1/10(5)) of pretrans plant CTL-p correlated with oligotyping identity in all donor-recipien t pairs evaluated. In one case oligotyping disclosed a previously unre cognized HLA-DRB1 disparity, This resulted in high frequencies of CTL- p (1/35,000), Based on this experience we can argue that CTL-p analysi s may be used as an additional tool for selection of compatible unrela ted marrow donors.