Robust SARS-CoV-2 T cell responses with common TCRαβ motifs toward COVID-19 vaccines in patients with hematological malignancy impacting B cells

Interim results from a phase I randomized, placebo-controlled trial of novel SARS-CoV-2 beta variant receptor-binding domain recombinant protein and mRNA vaccines as a 4th dose booster

“…Nonetheless, the frequency of activated CD4 + and CD8 + T cells was enhanced following vaccination with either Protein-RBD or mRNA-RBD vaccine, as measured by AIM assay, a method previously used to study overlapping Spike peptide-specific T cell responses following SARS-CoV-2 infection 18 , 19 and vaccination. 20 CD8 + T cell activation was more pronounced for the mRNA vaccine compared to the protein vaccine, which is consistent with other observations that protein-based vaccines have been shown to generate less CD8 + T cell responses compared to their CD4 + counterparts, as is reported for COVID-19 vaccine candidates 23 and inactivated influenza vaccines. 24 …”

“…Cells were washed and stained with CD8-BV605, CD4-BV650, and activation markers (CD137-APC, CD69-PerCPCy5.5, CD134-PE) and cytokines by intracellular staining (ICS), before fixing with 1% paraformaldehyde. 18 , 19 , 20 Cells were acquired on an LSRII Fortessa (Becton Dickinson) and data were analysed using FlowJo v10 (Becton Dickinson). Cellular activation in whole blood measuring the kinetics of antibody-secreting cells (ASCs) and activation of T follicular helper (Tfh)/CD8 + /CD4 + T cell subsets were assessed by directly staining whole blood with antibodies for flow cytometry, essentially as described.…”

Scientific highlights of the 9th ESWI Influenza Conference

“…Transitioning to COVID-19 vaccination research, Kedzierska discussed efforts to define immune responses in high-risk patients and First Nation people [27,49,50]. Indigenous populations globally are disproportionately affected by infectious diseases.…”

Vaccine schedule recommendations and updates for patients with hematologic malignancy post‐hematopoietic cell transplant or CAR T‐cell therapy

“… 67 , 70 , 71 Despite this, there does appear to be a preserved cellular immune response, even in patients treated with B‐cell‐depleting therapy, which has demonstrated prior importance in the severity of COVID‐19 infection. 66 , 72 , 73 , 74 In this context, the recommended primary course of vaccination is with three doses of COVID‐19 vaccine. 67 , 75 , 76 , 77 , 78 , 79 , 80 Seroresponse rates post three doses of vaccine are improved compared to two doses and have been estimated to be in the range of 63%–90% in autologous HCT recipients and 58%–90% in allogeneic HCT recipients.…”

“… 98 In hematology malignancy patients with diseases and treatments impacting B‐cell immunity, in those who received two doses of ChAdOx1 vaccination followed by an mRNA vaccine, even in the absence of seroconversion robust SARS‐CoV‐2‐specific T‐cell immunity was documented. 74 …”