PB0151 - Automated genotyped matching of platelets to prevent alloimmunisation

Sunday, July 10, 2022

6:30 PM – 7:30 PM

Location: Exhibition

Presentation Format: In-Person

Presenting Author(s)

NG

Nicholas Gleadall, PhD

Research Associate
University of Cambridge & NHS Blood and Transplant
Cambridge, England, United Kingdom

Co-Author(s)

RF

Renester Fenton

Clinical Nurse Specialist
Barts Health NHS Trust, Royal London Hospital
London, England, United Kingdom
DH

Daniel P. Hart

Consultant Haematologist
Royal London Hospital Haemophilia Centre, Royal London Hospital, Barts Health NHS Trust
London, England, United Kingdom
PW

Pascal Winter

Transfusion Practitioner
Department of Haematology, Barts Health NHS Trust, London, United Kingdom
London, England, United Kingdom
KL

Kurtis Lee

Haematology Scientific Lead
Haematology Laboratory, Royal London Hospital, Barts Health NHS Trust
London, England, United Kingdom
CB

Catherine Booth

Consultant Haematologist
Department of Haematology, Barts Health NHS Trust, London, United Kingdom and NHS Blood and Transplant, United Kingdom
London, England, United Kingdom
LW

Lindsay Walker

BGC Project Co-ordinator
Department of Haematology, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
Cambridge, England, United Kingdom
SS

Simon J. Stanworth, DPhil FRCP FRCPath

Professor
Oxford University Hospitals/NHS Blood and Transplant
Oxford, England, United Kingdom
BG

Blood transfusion Genomics Consortium

The Blood transfusion Genomics Consortium
Cambridge University Hospitals, Cambridge Biomedical Campus, Cambridge, UK.
Cambridge, England, United Kingdom
WO

Willem H. Ouwehand

Group Coordinator and Principal Investigator
University of Cambridge
Cambridge, England, United Kingdom
WA

William Astle

Senior Lecturer
University of Cambridge
Cambridge, England, United Kingdom
Suthesh Sivapalaratnam, MD, PhD, MRCP, FRCPath

Senior Clinical Lecturer
Barts Health NHS Trust
London, England, United Kingdom

Background: Immunisation against HLA antigens results in adverse healthcare outcomes and significantly increased costs for inherited platelet disorder (IPD) and haemato-oncology patients requiring platelet transfusions. In a single tertiary London centre two of 17 patients with Glanzmann Thrombasthenia or Bernard Soulier Syndrome are refractory to random platelets because of HLA-antibodies. Sourcing HLA-matched platelets for these patients is not possible and costly treatments with activated recombinant-Factor VII are required. These immunisations are avoidable with a sufficiently HLA-typed donor pool.

Aims: To apply population-scale genotyping for provision of HLA-matched platelets.

Methods: The Blood transfusion Genomics Consortium (BGC) has developed an affordable genotyping array capable of typing all red cell, platelet (HPA) and HLA antigens at two-field resolution. Validation has been performed using DNA samples from 14,000 donors from 7 BGC-participating blood services. HPA and HLA types were inferred from the data using the bloodTyper and HLA:IMPUTE02 algorithms.

Results: Genotyping demonstrated concordance of 99.03% at two-field resolution with clinically validated HLA typing results (Fig.1). Using the dense genotyping data for the donors in this study, we were able to identify 8 and 114 exact HLA matched donors for the two IPD patients with HLA-antibodies, where through standard care none could be identified due to a lack of HLA-typing data.

Conclusion(s): We present an affordable array-based genotyping platform which has immediate value in increasing the availability and match quality of HLA-matched platelet concentrates for IPD and Haemato-Oncology patients. Currently, regulatory approval is sought and the technology has been introduced in several national blood services. In the near future full HLA and HPA antigen types will become available for millions of donors worldwide, providing the opportunity to implement a policy of genomics-based precision platelet matching.