HLA-B35 is associated with red cell alloimmunization in sickle cell disease

Area of Science:

• Immunogenetics
• Hematology

Background:

• Sickle cell disease (SCD) patients often require red blood cell (RBC) transfusions.
• RBC transfusions can lead to alloimmunization, complicating future transfusions.
• Human Leukocyte Antigen (HLA) compatibility is crucial for transfusion success.

Purpose of the Study:

• To investigate the association between specific HLA antigens and the development of RBC alloantibodies in transfusion-dependent SCD patients.
• To identify HLA markers that predict alloimmunization risk in SCD.

Main Methods:

• HLA-A, -B, -C, and -DR antigen typing was performed on 33 SCD patients.
• Patients were categorized into responders (developed alloantibodies) and non-responders (did not develop alloantibodies) post-transfusion.
• Statistical analysis, including chi-squared test and relative risk calculation, was used.

Main Results:

• A significantly higher frequency of HLA-B35 was observed in SCD patients who developed RBC alloantibodies (67%) compared to non-responders (25%).
• The relative risk indicated that SCD patients with HLA-B35 are six times more likely to form RBC alloantibodies after transfusion.
• No significant association was found between HLA-DR antigens and RBC alloantibody formation.

Conclusions:

• The HLA-B35 antigen is a significant risk factor for RBC alloimmunization in sickle cell disease patients receiving transfusions.
• HLA-B35 typing may aid in personalized transfusion strategies to minimize alloantibody formation in SCD.
• Further research is warranted to explore the mechanisms underlying this association.