Human leukocyte antigen (HLA) typing is used to match patients and donors for bone marrow or cord blood transplants. HLA are proteins -- or markers -- found on most cells in your body. Your immune system uses these markers to recognize which cells belong in your body and which do not.

There are many HLA markers. Half are inherited from your mother and half from your father, so each brother and sister who shares the same parents as you has a 25% chance (1 in 4) of being a close HLA match. Extended family members are not likely to be close HLA matches. But about 70% (7 out of 10) of patients who need a transplant won’t have a fully matched donor in their family.

The traditional serological cytotoxicity method, flow cytometry, and solid-phase method are the three primary approaches for detecting HLA antibodies. Magnetic beads are utilized to segregate B lymphocytes from blood or spleen for HLA class II typing. HLA class I typing can be done with the remaining leucocytes.