What is HLA Typing? Why is Important Before Cord Blood Stem Cell Transplantation?

Earlier umbilical cord along with the cord blood used to be considered as a medical waste. But, since cord blood has been known to be rich with Haematopoietic stem cells, cord blood stem cell transplantation has come up as an effective treatment procedure with life-saving benefits.

However, the effectiveness can truly be felt when the receiver finds a perfect match from the donor of the stem cells for the transplantation. And to find a perfect or a near perfect match, before a stem cell transplant, HLA typing or matching has a major role to play.

What is HLA Typing?

HLA which stands for Human Leucocyte Antigen typing is basically a kind of genetic testing used to identify the variations in a person’s immune system. These are essentially protein markers found in many of the cells of the body. Mainly located in the white blood cells, the immune system of the human body with the help of these protein markers differentiate the cells that belong to the body from those that do not belong to the body. When two people have the same type, that can be considered as a “good match”, further indicating that, the transplantation can be carried out safely.

What Are Best Chances of Finding a Match?

Children inherit their HLAs from their parents. If there are two children in a family, both the siblings are supposed to receive the same type. But there is also a chance that, the two children, from the same family may not share the same HLA type.

Basically, there are many HLA markers and each has a name, segregated in letters and in the combination of letters and numbers, also known as haplotype or “half set of proteins”. That said, each child will receive half set of HLAs from the mother and the other half from the father.

But, since some HLA types are less common, getting a perfect match can be difficult. So, there’s a chance of finding 25% (1 in 4) close match between the siblings. In fact, there is 70% chance of finding a match within the extended family.

Research also has it that, a minimum of 6 HLA markers should match with the donor. A close match surely is a requirement, for a successful transplant outcome. And through a thorough testing the best match could be found.

 A near perfect match could also be found from certain racial and ethnic groups.

Why is HLA Typing or Matching Important Before a Stem Cell Transplant?  

When there is a need for stem cell transplantation, the doctor looks for the best possible donor or Cord Blood Unit for the patient and carry out the HLA Typing or Matching process, so that the body’s immune system does not reject the donor cells as a foreign body and develops complications like Graft-Versus_Host-Diseases. HLA typing or matching determines that the patient or the person receiving the stem cell transplantation for a condition can use the stem cells with safety, thus helping the donor cells to grow and make new blood cells.

Overall, ensuring a successful stem transplant.