Low incidence of de novo HLA antibodies after COVID‐19 vaccination: A cohort study of patients awaiting kidney transplantation

Abstract

AbstractBackgroundAntibodies against human leukocyte antigen (anti‐HLA Abs) are associated with an increased risk of allograft loss. Herein, we report the prospective follow‐up for anti‐HLA Abs formation in 103 patients with end‐stage kidney disease on the waiting list for transplantation who underwent COVID‐19 vaccination.Patients and methodsSera were tested before and after vaccination using Luminex technology. The cohort comprised of 62 males and 41 females with a mean age of 56 ± 14 years. The patients received BNT162b2 (80.4%), mRNA‐1273 (18.5%), AZD1222 (0.40%), or ChAdOx1‐S (0.80%) vaccine. Patients were tested before and within 119 ± 50, 95 ± 46 and 25 ± 26 days after the first, second, and third dose of the vaccine, respectively.ResultsNo significant change in calculated panel reactive antibody (cPRA) after vaccination was seen. Although 98.1% of patients had no change in anti‐HLA Abs profile or cPRA after vaccination, two patients (1.9%) developed de novo anti‐HLA Abs against class I or II HLA antigens. In those two patients, the cPRA changed from 0% and 63% at baseline to 9% and 90% after vaccination, respectively. Both patients received the BNT162b2 mRNA‐based vaccine. The earliest detected anti‐HLA Abs was 18 days after the first dose.ConclusionIn rare cases, new anti‐HLA antibodies were observed after COVID‐19 vaccination, with potential implications for transplantation. The low incidence of this phenomenon is outweighed by the clinical benefits of vaccination. image