P1623: ROLE OF HLA GENES IN DEVELOPMENT OF HLA-ALLOIMMUNIZATION IN BLOOD RECIPIENTS

Abstract

Background: The main adverse effects of HLA-alloimmunization are transfusion failure and the need for additional platelet transfusions, febrile reactions, and the threat of fatal bleeding. The individual prediction of the risk of alloimmunization remains an unresolved problem. It seems relevant to study the relationship between the HLA genotype and the probability of alloimmunization of recipients as a result of blood transfusions. Aims: Assess the genetic predisposition of recipients to the development of HLA alloimmunization. Methods: Immunohematological and genetic studies were performed in 61 patients (22 men and 39 women) who received from 6 to 32 transfusions of blood components (median 11) during the previous treatment in a hematology clinic in 2019-2021. All blood components were leukoreduced. Patient age ranged from 3 to 78 years (median 48 years). Acute leukemia was diagnosed in 34 patients, myelodysplastic syndrome - in 10, aplastic anemia - in 8, other blood diseases - in 9. Typing of HLA DRB1, DQA1, DQB1 gene was performed by real-time polymerase chain reaction using equipment and reagents from DNA- technology (Russia). Statistical analysis was performed using the chi-square test. Results: Based on the results of the study of antilymphocyte antibodies, patients were divided into two groups: HLA-nonimmunized (n=31) and HLA-immunized (n=30). The Panel Reactive Antibody in 3 out of 30 alloimmunized patients was 25-49%, in 12 - 50-74%, in 15 patients - 75-100%. When analyzing the results of immunogenetic examination, statistical differences were established in the frequency of detection of HLA-alleles and haplotypes in the genotypes of HLA-alloimmunized and nonimmunized recipients (Table). Table. - Frequency of detection of HLA-DRB1-DQA1-DQB1 haplotypes in HLA-alloimmunized and HLA-non-alloimmunized patients HLA-DRB1-DQA1-DQB1 haplotypes Frequency of detection of HLA haplotypes p HLA-nonalloimmunized patients, n=31 HLA- alloimmunized patients, n=30 абс. % абс. DRB1*15-DQA1*01:02-DQB1*06:02-8 14 45.2 7 23.3 0.12 DRB1*01-DQA1*01:01-DQB1*05:01 12 38.7 9 30 0.65 DRB1*03-DQA1*05:01-DQB1*02:01 2 6.5 8 26.7 0.07 DRB1*04-DQA1*03:01-DQB1*03:02 1 3.2 9 30 0.01 DRB1*07-DQA1*02:01-DQB1*02:01 4 12.9 6 20 0.69 DRB1*13-DQA1*01:03-DQB1*06:02-8 3 9.7 7 23.3 0.27 DRB1*16-DQA1*01:02-DQB1*05:02 6 19.4 0 0 0.03 DRB1*11-DQA1*05:01-DQB1*03:01 3 9.7 4 13.3 0.96 Summary/Conclusion: A genetically determined predisposition to the development of HLA-alloimmunization as a result of blood transfusions is associated with the presence of HLA-alleles DRB1*04, DQA1*03:01, DQA1*05:01 and HLA-haplotype DRB1*04-DQA1*03:01-DQB1*03:02 in the genotypes of recipients. The probability of antibody production is reduced in patients with HLA-alleles DRB1*16, DQA1*01:02, DQB1*05:02 and HLA-haplotype DRB1*16-DQA1*01:02-DQB1*05:02.