Anti-HLA Immunization in Patients After Lung Transplantation: A Comparative Study Before and During the Pandemic

Anti-human leukocyte antigen (anti-HLA) sensitization in lung transplant recipients (LTRs) can significantly impact graft survival and patient outcomes. The global pandemic, induced by the SARS-CoV-2 virus, brought about numerous challenges in the medical sphere, including potential alterations in HLA immunization patterns among LTRs. A retrospective analysis of LTRs group transplanted from July 2018 to 1 March 2020 (pre-pandemic) was compared with patients transplanted from 1 March 2020 to December 2022 (during the pandemic). Totally 92 patients were controlled. Patients were also divided into 2 groups: vaccinated and non-vaccinated. The results of cytotoxic crossmatch, results of anti-HLA antibody testing, presence of DSA before and after transplantation, and early and late graft function were compared between groups. In the pandemic and vaccinated groups, an increase was observed in the number of positive crossmatch tests performed with a pool of B lymphocytes. However, the presence of dithiothreitol abolished the positive reaction in 90% of cases. We also observed an increased percentage of patients immunized based on the results of solid phase tests both in the pandemic group and in the group of patients who received vaccination against the SARS-CoV-2 virus. It might be that the pandemic/vaccination has influenced the prevalence of anti-HLA immunization in LTRs. Further studies are essential to establish causative factors and develop targeted interventions for this population of patients.