Human leukocyte antigens A and B Loci genotyping by reference strand-mediated conformation analysis in hematopoietic stem cell transplantation donor selection.

Research has been carried out to evaluate the reference strand-mediated conformation analysis (RSCA) typing method on human leukocyte antigen (HLA)-A and -B loci matching in donor selection for hematopoietic stem cell transplantation (HSCT). Twenty standard DNA samples from the RSCA program of the 13th International Histocompatibiliy Working Group, and 124 DNA samples extracted from peripheral blood cells of 39 patients and 85 related potential donors were typed both by RSCA and polymerase chain reaction sequence-specific primer (PCR-SSP) for their HLA-A and -B genes. The ambiguous results were further confirmed by sequence-based typing (SBT). HLA-A and -B genotypes assigned by RSCA correlated well with PCR-SSP and the repetitive rate of RSCA was 100%. In our study, 33/84 (39%) and 67/90 (72.8%) RSCA genotyping results of HLA-A and -B loci could be typed to allelic level, respectively. RSCA can detect mismatches that are not routinely identified by the PCR-SSP method and can detect the chimerism status after patients have gone through HLA-mismatched HSCT. Eight ambiguous samples were confirmed by SBT and the results indicated that RSCA was more accurate than low-resolution PCR-SSP and its database should be improved. RSCA is reproducible, has a high resolution, is able to detect chimerism follow-up after HLA-mismatched HSCT, and is a useful approach for donor selection with some insufficiencies to be improved.