The very first trial of stem cell transplantation (SCT) was carried in nuclear workers exposed to radiation. Later, this procedure developed into a successful treatment option that can cure patients affected with haematological malignancies and disorders (1). In case of a matching donor, the success rate of SCTs can be as high as 90% when conditions are detected in early stages (1).
Globally, more than 50,000 transplants are carried out annually and then the number is increasing each year (1). SCTs offer hope to patients who are in the advanced stage of the disease or are suffering from conditions that are non-responsive to the treatment.
SCTs are primarily of two types (1):
- Allogeneic SCT: The patient uses stem cells from a donor. A donor can be a family member or not related to the recipient.
- Autologous SCT: The patients use their own stem cells.
The success of these transplants depends on various factors including patient’s overall health, disease stage, and availability of a compatible/matching donor. This is where the role of human leukocyte antigens (HLA) becomes critical.
The degree of HLA match between the donor and the recipient is an important factor in deciding the outcome of the transplantation. Let us understand what HLA is and its importance in detail.
Human leukocyte antigens are proteins that are expressed on almost all cells. They are primarily responsible for the immune response of the body and help in differentiating our own cells from foreign bodies (2). Interestingly, each individual has a unique set of antigens which are inherited from the parents—50% from the mother and 50% from the father (2).
- HLA & Stem cell transplantation
HLA matching/typing is used to match donors and recipients and is much more complex than blood typing. Principally, 8 HLA types or markers are important for SCTs. Detailed testing is required for finding the best match (3).
- For a bone marrow transplant, a match of all 8 markers (100%) is required.
- For a cord blood transplant, a match of at least 6 of 8 (75%) markers is required.
A close HLA match between a donor and recipient is critical for a successful transplant because of the following reasons (4):
- Improves the chances of a successful transplant.
- Promotes engraftment (growth & development of healthy blood cells).
- Reduces the risk of complications including graft-versus-host disease (GVHD).
Challenges of finding a match in India
Sometimes, it is difficult to find a match because of the following reasons (1, 4).
- Siblings from the same parents have a 25% chance (1 in 4) of being a close HLA match.
- Extended family members are highly unlikely to be a close match.
- About 70% of patients who need a transplant do not have a matched family donor.
Moreover, ethnicity and racial background is also an important factor. A few HLA markers are more common than the others or are found more often in certain ethnicities (1, 4). Therefore, a person’s best chance of finding a match is more likely to be with a donor of similar ethnic background.
Challenges of finding a match in India are undeniable due to the following reasons:
- Because of the diverse Indian population, the chance of finding a genetically matched donor may range from 1 in 10,000 to 1 in 2,000,000.
- High donor dropout rates.
- Public bank limitations
- In a public bank, the probability of finding a matching donor is <10%.
- Low inventory (repository contains approx. 6500 units only)
- Lack of funds for the functioning of the registry.
How LifeCell Community Banking Helps
Lifecell Community Banking works on the concept of sharing preserved stem cells exclusively amongst its community members to find matching donor stem cells. With over 50,000 qualified & consented cord blood units available for allogeneic SCT (8 times of all public banks in India), there is 97% chance of finding a matching unit for an Indian patient.
LifeCell, India’s best matchmaker, is now offering StemMatch, a one-of-its-kind exclusive service to enrolled stem cell banking customers.
With this test, you can now readily know the exact number of 6/8, 7/8 & 8/8 matching stem cell units available for your cord blood sample in the LifeCell registry, the largest repository of Indian origin stem cells. All it takes is 3 simple steps!
- Sign up
- Sample collection: Cord blood for the child and peripheral blood for the adults
- Comprehensive results shared in 20 days
You can now avail following value-added offerings!
- Any member of the family can avail it.
- Reduced testing & matching time for expedited stem cell transplantation process.
- Affordable pricing for trusted customers @ INR 9,999 per person
- Updated status based on new samples added in or retrieved from the registry with no additional cost
Would you like to know more, call 1800 266 5533 or SMS ‘LIFECELL’ to 53456
- Haematopoietic Stem Cell Transplantation HSCtx. World Health Organization. Available from: https://www.who.int/transplantation/hsctx/en/#:~:text=Stem%20cell%20transplantation%20can%20be,or%20from%20the%20peripheral%20blood.
- Berger A. HLA typing. Bmj. 2001 Jan 27;322(7280):218.
- What is HLA type and how is it used?. Parent's Guide to Cord Blood Foundation. Available from: https://parentsguidecordblood.org/en/faqs/what-is-hla-type-and-how-is-it-used
- HLA basics. BeTheMatch. Available from: https://bethematch.org/transplant-basics/matching-patients-with-donors/how-donors-and-patients-are-matched/hla-basics/