Identification of the novel HLA-DRB1*15:184 allele by Next-Generation Sequencing

HLA-DRB1*15:184 differs from HLA-DRB1*15:01:01 by a single base substitution in exon 3 at codon 134. This article is protected by copyright. All rights reserved.

Identification of the novel HLA-B*42:28 allele by Next-Generation Sequencing

HLA-B*42:28 differs from HLA-B*42:01:01 by a single base substitution in exon 4 at codon 267.2. This article is protected by copyright. All rights reserved.

BSHI/BTS guidance on crossmatching before deceased donor kidney transplantation

All UK H&I laboratories and transplant units operate under a single national kidney offering policy, but there have been variations in approach regarding when to undertake the pre‐transplant crossmatch test. In order to minimize cold ischaemia times for deceased donor kidney transplantation we sought to find ways to be able to report a crossmatch result as early as possible in the donation process. A panel of experts in transplant surgery, nephrology, specialist nursing in organ donation and H&I (all relevant UK laboratories represented) assessed evidence and opinion concerning five factors that relate to the effectiveness of the crossmatch process, as follows: when the result should be ready for reporting; what level of donor HLA typing is needed; crossmatch sample type and availability; fairness and equity; risks and patient safety. Guidelines aimed at improving practice based on these issues are presented, and we expect that following these will allow H&I laboratories to contribute to reducing CIT in deceased donor kidney transplantation.

HLA-A, -B and -DR antigen frequencies of the London Cord Blood Bank units differ from those found in established bone marrow donor registries

Patients requiring allogeneic stem cell transplantation who do not have an HLA-matched related donor can sometimes obtain an unrelated donor by searching volunteer registries. The majority of donors in the registries are Caucasoid, which results in a lower probability of a non-Caucasoid patient finding a suitable donor. Cord blood is increasingly used as a source of haematopoietic stem cells for allogeneic bone marrow reconstitution and so far the London Cord Blood Bank has banked almost 3000 cord blood units. An analysis of the first 1500 units banked showed that more than 30% of the London Cord Blood Bank units are derived from UK ethnic minorities compared with only 2% of individuals recruited locally for the British Bone Marrow Registry (BBMR). The HLA types found in these cord blood units reflect their ethnic diversity and include: HLA-A34, A36, A80, B75, B61, B53, B78, B81 and B82. The units stored by the London Cord Blood Bank show an HLA profile which differs considerably from that of locally typed adult volunteers for the BBMR panel and this should help to increase the chances of obtaining acceptably HLA-matched donors for patients from ethnic minorities. Bone Marrow Transplantation (2000) 25, 475-481.

HLA-A typing by reference strand-mediated conformation analysis (RSCA) using a capillary-based semi-automated genetic analyser

HLA typing of class I loci by reference strand-mediated conformation analysis (RSCA) using a slab gel genetic analyser has been described. This study adapted the method for use in the capillary based ABI PRISM 310. Control DNA samples were used to create a database of mobility values for 37 HLA-A alleles. The technique was validated by comparing RSCA and sequence-specific oligonucleotide probe (SSOP)/sequence-specific primer amplification (SSP) HLA-A locus typing results from 214 cord blood samples. Of the samples tested, 6.5% required confirmatory typing by SSP, compared with a repeat rate of 10-40% for SSOP. In 200 samples where no SSP was necessary, there was 100% concordance between RSCA and previous results. The ABI PRISM 310 RSCA method defines HLA-A types at medium resolution and is quick and easy to implement.