1. Robust spike-specific CD4+ and CD8+ T cell responses in SARS-CoV-2 vaccinated hematopoietic cell transplantation recipients: a prospective, cohort study.
- Author
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Federico, Lorenzo, Tvedt, Tor Henrik Anderson, Gainullin, Murat, Osen, Julie Røkke, Chaban, Viktoriia, Lund, Katrine Persgård, Tietze, Lisa, Tran, Trung The, Lund-Johansen, Fridtjof, Kared, Hassen, Lind, Andreas, Vaage, John Torgils, Stratford, Richard, Tennøe, Simen, Malone, Brandon, Clancy, Trevor, Myhre, Anders Eivind Leren, Gedde-Dahl, Tobias, and Munthe, Ludvig André
- Subjects
HEMATOPOIETIC stem cell transplantation ,T cells ,COVID-19 ,SARS-CoV-2 ,VACCINE effectiveness ,BCG vaccines ,T cell receptors - Abstract
Poor overall survival of hematopoietic stem cell transplantation (HSCT) recipients who developed COVID-19 underlies the importance of SARS-CoV-2 vaccination. Previous studies of vaccine efficacy have reported weak humoral responses but conflicting results on T cell immunity. Here, we have examined the relationship between humoral and T cell response in 48 HSCT recipients who received two doses of Moderna's mRNA-1273 or Pfizer/BioNTech's BNT162b2 vaccines. Nearly all HSCT patients had robust T cell immunity regardless of protective humoral responses, with 18/48 (37%, IQR 8.679-5601 BAU/mL) displaying protective IgG anti-receptor binding domain (RBD) levels (>2000 BAU/mL). Flow cytometry analysis of activation induced markers (AIMs) revealed that 90% and 74% of HSCT patients showed reactivity towards immunodominant spike peptides in CD8
+ and CD4+ T cells, respectively. The response rate increased to 90% for CD4+ T cells as well when we challenged the cells with a complete set of overlapping peptides spanning the entire spike protein. T cell response was detectable as early as 3 months after transplant, but only CD4+ T cell reactivity correlated with IgG anti-RBD level and time after transplantation. Boosting increased seroconversion rate, while only one patient developed COVID-19 requiring hospitalization. Our data suggest that HSCT recipients with poor serological responses were protected from severe COVID-19 by vaccine-induced T cell responses. [ABSTRACT FROM AUTHOR]- Published
- 2023