D6STNFa microsatellite locus correlates with CTLp frequency in unrelated bone marrow donor-recipient pairs

The use of unrelated donors for bone marrow transplantation is associated with an increased morbidity and mortality when compared with HLA identical siblings, primarily due to an increased rate of graft-versus-host-disease. HLA matching for donors and recipients is the most important factor influencing the outcome of BMT. However, unrelated donor selection generally relies on matching only for HLA antigens without considering potential incompatibility for other MHC loci. Cellular assays have been developed to predict incompatibility that cannot be detected by current typing methods. The CTLp frequencies correlate with the degree of incompatibility of patient/donor and the clinical grade of GVHD. Since the CTLp assay is expensive and time consuming, an alternative is wanted. We studied the means of matching for microsatellites in determining MHC identity and possible correlation with CTLp frequencies. Therefore, 26 recipient/donor pairs were analysed for eleven microsatellite loci within and around the MHC region. Our study provides evidence that the D6STNFa locus correlates with CTLp frequency. The D6STNFa locus provides an additional marker that may help to improve the matching of unrelated donors and bone marrow recipients.