Metabolic impairments in peripheral blood mononuclear cells after BNT162b2 vaccination in liver transplantation adolescents

The mRNA vaccine BNT162b2 was approved to prevent COVID-19 disease in adolescents. Currently, there are no data on cellular metabolism in adolescents receiving liver transplantation (LT) before and after SARS-CoV-2 vaccination. This study aimed to investigate the effects of the BNT162b2 mRNA vaccine on cellular metabolism in LT adolescents compared to healthy adolescents. The bioenergetics study was performed using the PBMCs of 15 LT adolescents and 15 healthy adolescents aged between 12 and 18 years. All participants received 30 µg of BNT162b2 on days 0 and 21. Blood samples were collected at 3 time points: before vaccination (day 0), on day 21 and on day 35 after the first dose. Mitochondrial respiration and glycolysis in the frozen PBMCs were measured by using a Seahorse XFp analyzer. The results showed that LT adolescents had a lower oxygen consumption rate (OCR) during mitochondrial respiration than healthy adolescents at all time points. Additionally, LT adolescents exhibited reduced glycolysis, as indicated by a lower extracellular acidification rate (ECAR), throughout the study period. These findings suggest that impairments in mitochondrial and glycolytic metabolism observed in PBMCs from LT adolescents after BNT162b2 vaccination may contribute to the early suppression of the immune response. Future studies should evaluate which immune cells are critical for metabolic dysfunctions.