Introduction: Organ transplantation's success relies on intricate compatibility assessments involving human leukocyte antigens (HLA) and antibodies. This study aims to explore the underreported role of HLA-DRB3, DRB4, and DRB5 gene products (DR51, DR52, DR53) in kidney transplant practices, particularly in Argentina, where the HLA Typing Kit includes these genes, yet lacks specific legislation dictating which loci should be analyzed and reported in deceased donors for transplantation, introducing uncertainty into the HLA typing process and reports.
Method: The study examined 25 HLA typings and 141 flow cytometry crossmatch (FC-XM) reports over three months to assess the presence of DR51, DR52, and DR53 antigens and their potential impact on organ allocation. Additionally, it considered the use of PCR-SSP (low resolution) for HLA typing, aligned with serology that SINTRA demands, and the limitations of the SAB assay in providing allele-specific information about antibodies.
Results: Among the HLA typings analyzed, each revealed the presence of at least one HLA DR51, DR52, or DR53 antigen, with various combinations observed. Notably, all twenty-five donation processes had the potential to encounter recipients with anti-HLA DR51/52/53 antibodies. In the FC-XM reports, only three resulted in 'T cell negative/B cell positive' outcomes with HLA DR51/52/53 uploaded as unacceptable antigens and present in the donor. Furthermore, the study highlighted discrepancies in antibody detection between PCR-SSP and the SAB assay, underscoring a potential limitation in the study methodology.
Conclusion: This research emphasizes the need for inclusive reporting practices and further research on the clinical impact of anti-HLA DR51/52/53 antibodies in solid organ transplantation. By integrating DRB3, DRB4, and DRB5 data into HLA typing reports, we can leverage existing technology to address potential roles of these antigens in rejection episodes, paving the way for advancements in organ allocation and improved outcomes in kidney transplantation.