Abstract
Allogeneic haematopoietic stem cell transplant (HSCT) recipients remain at high risk of adverse outcomes from coronavirus disease 2019 (COVID-19) and emerging variants. The optimal prophylactic vaccine strategy for this cohort is not defined. T cell-mediated immunity is a critical component of graft-versus-tumour effect and in determining vaccine immunogenicity. Using validated anti-spike (S) immunoglobulin G (IgG) and S-specific interferon-gamma enzyme-linked immunospot (IFNγ-ELIspot) assays we analysed response to a two-dose vaccination schedule (either BNT162b2 or ChAdOx1) in 33 HSCT recipients at ≤2 years from transplant, alongside vaccine-matched healthy controls (HCs). After two vaccines, infection-naïve HSCT recipients had a significantly lower rate of seroconversion compared to infection-naïve HCs (25/32 HSCT vs. 39/39 HCs no responders) and had lower S-specific T-cell responses. The HSCT recipients who received BNT162b2 had a higher rate of seroconversion compared to ChAdOx1 (89% vs. 74%) and significantly higher anti-S IgG titres (p = 0.022). S-specific T-cell responses were seen after one vaccine in HCs and HSCT recipients. However, two vaccines enhanced S-specific T-cell responses in HCs but not in the majority of HSCT recipients. These data demonstrate limited immunogenicity of two-dose vaccination strategies in HSCT recipients, bolstering evidence of the need for additional boosters and/or alternative prophylactic measures in this group.
Keywords: BNT162b2; ChAdOx1; T-cell response; allogeneic bone marrow transplant; coronavirus disease 2019 (COVID-19); haematopoietic stem cell transplant (HSCT); severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2); vaccines.
【저자키워드】 T-cell Response, Coronavirus disease 2019 (COVID-19), Vaccines., BNT162b2, Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), ChAdOx1, allogeneic bone marrow transplant, haematopoietic stem cell transplant (HSCT), 【초록키워드】 COVID-19, coronavirus disease, IgG, Coronavirus disease 2019, Vaccine, Vaccines, T-cell Response, interferon, Prophylactic, severe acute respiratory syndrome Coronavirus, variants, adverse outcomes, Bone marrow, adverse outcome, BNT162b2, Severe acute respiratory syndrome, Cohort, Immunoglobulin G, Seroconversion, Immunoglobulin, Transplant, Allogeneic, T-cell, respiratory, Critical, ChAdOx1, ImmunoSpot, booster, T-cell responses, Cell-mediated immunity, Anti-spike, anti-S IgG, Coronavirus-2, Evidence, Vaccination strategy, vaccine immunogenicity, high risk, HSCT, stem cell, evidence of, prophylactic measures, prophylactic measure, acute respiratory syndrome, acute respiratory syndrome coronavirus, enzyme-linked immunospot, healthy control, These data, IFNγ, acute respiratory syndrome coronavirus-2, titre, responders, recipient, significantly lower, vaccination schedule, Cell, HSCT recipients, defined, analysed, majority, significantly higher, HCs, HSCT recipient, rate of seroconversion, 【제목키워드】 COVID-19 vaccination, Patient, Allogeneic, cellular response, humoral, less, Impaired,