Time filter

Source Type

Dunn P.P.J.,Tissue Typing Laboratory | Hammond L.,Tissue Typing Laboratory | Coates E.,Welsh Transplantation and Immunogenetics Laboratory | Street J.,Welsh Transplantation and Immunogenetics Laboratory | And 2 more authors.
Human Immunology | Year: 2011

A Welsh Bone Marrow Donor Registry donor was serologically typed, using both alloantisera and monoclonal antibodies, as human leukocyte antigen (HLA)-A2, A-, but typed by polymerase chain reaction sequence-specific priming as HLA-A*01, A*02. Full gene sequencing of the A*01 separated allele indicated an apparently normal A*01:01:01:01 apart from a silent change at nucleotide 705 in exon 4, codon 211 (alanine: normally GCG but GCA in this donor). Sequence analysis of the amplified A*01 allele in cDNA synthesized from RNA indicated that exons 1, 2, 3, and 5 had typical A*01:01 sequences. However, exon 4 was truncated in this allele (87 nucleotides shorter), beginning just after the single nucleotide polymorphism (SNP) identified in genomic DNA sequencing. The nucleotide sequence up to, and 1 nucleotide after, the SNP is homologous with the 3' end of human leukocyte antigen (HLA)-A intron 3 and thus resembles a splice site. However, a small amount of "normal" HLA-A1 was detected on the surface of cells from an Epstein-Barr virus transformed B-cell line (BCL), but not on peripheral blood mononuclear cells, by flow cytometry. Additionally, a trace amount of "normal sized" A*01 was amplified from cDNA. We suggest that in this A*01 variant allele (A*01:01:38L) intron 3 is largely spliced out with a part of exon 4; exon 4 is still in-frame but the protein is smaller than the wild type. This is likely to affect folding and assembly of the "wild type" mature protein on the cell surface, thus explaining the apparent null phenotype when assayed by conventional serology. However, a small amount of A1 protein is made from correctly spliced A*01 mRNA and is detectable on BCLs using flow cytometry. © 2011 American Society for Histocompatibility and Immunogenetics.


Darke C.,Welsh Transplantation and Immunogenetics Laboratory | Corbin S.A.,Welsh Transplantation and Immunogenetics Laboratory
International Journal of Immunogenetics | Year: 2014

Hypersensitivity reactions to the drug abacavir are strongly associated with possession of HLA-B*57:01. Hence, patients with HIV/AIDS who may be prescribed abacavir should be tested for this HLA allele and the drug withheld from those that possess B*57:01. The UK National External Quality Assessment Service for Histocompatibility and Immunogenetics has operated a scheme for B*57:01 testing since 2008 which, in 2013, involved 47 participants from 12 countries. A total of 24 B*57:01-positive, 2 B*57:03-positive and 22 B*57-negative blood samples (including 2 B*58 samples) were distributed to between 28 and 47 laboratories each year over 6 years. Participants, who were unaware of the samples' HLA types, tested and reported on their B*57/B*57:01 status. A total of 1868 reports were assessed over the 6 years. Of the 880 reports on B*57:01 samples, 93.4% were correctly assigned as B*57:01, 2.8% were assigned as groups of B*57 alleles including B*57:01, and 3.3% were reported as B*57 positive only. Over the 6 years, there were four (0.46%) false B*57:01 negative reports. All the B*57:03-positive and B*57-negative samples, involving 72 and 916 assignments, respectively, were essentially reported as B*57:01 negative. Thus, there were no false B57:01 positive assignments. The reporting of B*57:01 status over the last 3 years of the scheme was 99.8% sensitive and 100% specific. Over the last year, it was 100% sensitive and 100% specific. © 2014 John Wiley & Sons Ltd.


Bengtsson M.,Uppsala University | Street J.,Welsh Transplantation and Immunogenetics Laboratory | Johnson J.,Welsh Transplantation and Immunogenetics Laboratory | Harvey C.,Welsh Transplantation and Immunogenetics Laboratory | And 2 more authors.
Tissue Antigens | Year: 2014

HLA-A*03:162N differs from A*03:01:01:01 by an exon 4, 664-665insCATG causing E198A and A199X. © 2013 John Wiley & Sons A/S.


Street J.,Welsh Transplantation and Immunogenetics Laboratory | Bengtsson M.,Uppsala University | Johnson J.,Welsh Transplantation and Immunogenetics Laboratory | Harvey C.,Welsh Transplantation and Immunogenetics Laboratory | Darke C.,Welsh Transplantation and Immunogenetics Laboratory
Tissue Antigens | Year: 2014

HLA-B*27:05:25 differs from B*27:05:02 by a single synonymous nucleotide substitution (192C>T) at codon 40 in exon 2. © 2014 John Wiley & Sons A/S.


Street J.,Welsh Transplantation and Immunogenetics Laboratory | Johnson J.,Welsh Transplantation and Immunogenetics Laboratory | Pepperall J.,Welsh Transplantation and Immunogenetics Laboratory | Darke C.,Welsh Transplantation and Immunogenetics Laboratory
Tissue Antigens | Year: 2014

HLA-A*01:139 differs from A*01:01:01:01 by one nucleotide (383G>C) resulting in an amino acid change of glycine104alanine. © 2013 John Wiley & Sons A/S.


Lemin A.J.,Welsh Transplantation and Immunogenetics Laboratory | Darke C.,Welsh Transplantation and Immunogenetics Laboratory
International Journal of Immunogenetics | Year: 2014

Two hundred and fifty-four normal blood donors, from a largely UK European population, were sequence-based typed for HLA-A, HLA-B, HLA-C, HLA-DRB1, HLA-DQA1 and HLA-DQB1. The fit to Hardy-Weinberg expectations was good for all loci (all P values >0.5). Fifteen DQA1 alleles were identified to the second field. DQA1 carriage, allele and DQA1-DQB1 and DRB1-DQA1-DQB1 haplotype frequencies, linkage disequilibria and related values are presented. © 2014 John Wiley & Sons Ltd.


Darke C.,Welsh Transplantation and Immunogenetics Laboratory | Coates E.,Welsh Transplantation and Immunogenetics Laboratory
Cytometry Part B - Clinical Cytometry | Year: 2010

Background: Flow cytometry-based methods are widely used to detect the ankylosing spondylitis-associated HLA-B27/B2708 antigens. However, the generally used "HLA-B27" monoclonal antibodies (moabs) cross-react with many HLA specificities, including the common HLA-B7 antigen. Thus, using two "B27" moabs is highly recommended. Methods: The assay used two "HLA-B27" reagents, FITC and PE conjugated, respectively and a PE-Cy5 anti-CD3 antibody. Assay verification used 51 reference subjects possessing B*2705, B*2702, and B*2708 and a range of cross-reactive HLA antigens. A total of 1,006 consecutive patients' samples, referred for "HLA-B27 typing", were assayed alongside our standard flow cytometry method. A further 12 low frequency HLA-B*27 specificities were tested. Samples reacting with one "B27" moab only were B*27 allele typed by PCR using sequence-specific primers. Results: All patient B27/B2708 positives (28.3%) were identified by our one-tube method which detected B*2705, B*2702, B*2708, and 8/12 other B*27 specificities. It was unaffected by HLA-B7 and other cross-reactive antigens but required a minor adjustment, a reduction in the volume of one of the "B27" moabs used, to avoid detecting a minority of HLA-B57 subjects. Conclusions: Our one-tube B27/B2708 assay is simple, robust, uses two "B27" moabs for typing precision and security, does not suffer from interference by HLA-B7 or other cross-reactive antigens and has the obvious advantage of using a single tube per typing. © 2009 Clinical Cytometry Society.


Street J.,Welsh Transplantation and Immunogenetics Laboratory | Johnson J.,Welsh Transplantation and Immunogenetics Laboratory | Pepperall J.,Welsh Transplantation and Immunogenetics Laboratory | Darke C.,Welsh Transplantation and Immunogenetics Laboratory
Tissue Antigens | Year: 2013

HLA-A*26:92 differs from A*26:01:01 by seven bases in exon 2 resulting in six amino acid substitutions. © 2013 John Wiley & Sons A/S.


Street J.,Welsh Transplantation and Immunogenetics Laboratory | Harvey C.,Welsh Transplantation and Immunogenetics Laboratory | Cook E.,Welsh Transplantation and Immunogenetics Laboratory | Johnson J.,Welsh Transplantation and Immunogenetics Laboratory | Darke C.,Welsh Transplantation and Immunogenetics Laboratory
Tissue Antigens | Year: 2015

Three novel HLA-DQB1 alleles were found after sequence-based typing of 3558 random UK European routine blood donors. © 2015 John Wiley & Sons A/S.


Street J.,Welsh Transplantation and Immunogenetics Laboratory | Climer T.,Welsh Transplantation and Immunogenetics Laboratory | Johnson J.,Welsh Transplantation and Immunogenetics Laboratory | Pepperall J.,Welsh Transplantation and Immunogenetics Laboratory | Darke C.,Welsh Transplantation and Immunogenetics Laboratory
Tissue Antigens | Year: 2015

HLA-A*26:103 differs from A*26:01:01 by one base (559C>G) in exon 3 resulting in an amino acid substitution of R163G. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Loading Welsh Transplantation and Immunogenetics Laboratory collaborators
Loading Welsh Transplantation and Immunogenetics Laboratory collaborators