Human Leukocyte Antigen (HLA) matching
HLA are six proteins (three HLA groups, A, B, DR) that appear on the surface of white blood cells and other tissues in the body. These six HLA points determine tissue compatibility between a patient and a donor. The higher the tissue compatibility, the higher are the chances of a transplant to be successful. Although a perfect match is always preferred, studies have shown successful cord blood transplants even when there is a match of only three or four of the six HLA points.