The USA guidelines for cord blood selection recommend a minimum 4/6 (HLA-A, -B antigen, -DRB1 allele/ARD) match as asuitable option for some patients. Some of the WMDA member organisations have implemented to run a routine HLA-A, -B antigen, -DRB1 allele/ARD cord search with up to two mismatches as a default. Therefore, WMDA is implementing this option as well in Search & Match Service.
A, B Antigen, DRB1 ARD level CBU searches are now available in the sandbox environment (https://sandbox-search.wmda.info/).
It was built to function in the same way as was implemented in legacy Search & Match. This means that:
- Allele matching is used to calculate overall and locus-specific match probabilities.
- Match class (e.g. 5/6, 4/6) is based on Antigen level matching at the A* and B* locus whereas regular matching at antigen recognition domain (ARD) level is used for DRB1.
After confirming it works correctly we will make it available in the production environment (https://searchmatch.wmda.info/)
Please help us in testing this feature. Please contact us at support@wmda.info if you have any questions.
Known behaviour.
As mentioned, CBUs are assigned the right match class (6/6 vs 5/6 vs 4/6) in A, B Antigen, DRB1 ARD level CBU searches. We are aware of a small issue. In some cases we may not indicate that a locus has a mismatch where there is one. This is only the case in A, B Antigen, DRB1 ARD level CBU searches and not in regular searches. We are working on a fix for this.