Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Cytomegalovirus (CMV) is a globally ubiquitous pathogen with a seroprevalence of approximately 50% in the UK. CMV infection induces expansion of immunosenescent T cell and NK cell populations with these cells demonstrating lower responsiveness to activation and reduced functionality upon infection and vaccination. In this study, we found that CMV+ participants had normal T cell responses after single dose or homologous vaccination with the viral vector ChAdOx1. In contrast, CMV seropositivity was associated with a loss of T cell IFN-γ secretion following heterologous ChAd-MVA viral vector vaccination. Analysis of participants receiving a single dose of ChAdOx1 demonstrates that T cells from CMV+ donors have a more terminally differentiated profile of CD57+PD1+ CD4+ T cells and CD8+ T cells expressing less IL-2Rα (CD25), and fewer polyfunctional CD4+ T cells 14 days post-vaccination. NK cells from CMV-seropositive individuals also have a reduced activation profile. Overall, our data suggest that although CMV infection enhances immunosenescence of T and NK populations, it does not affect antigen-specific T cell IFN-γ secretion or antibody IgG production after vaccination with the current ChAdOx1 nCoV-19 vaccination regimen in the UK.

Original publication

DOI

10.1172/jci.insight.154187

Type

Journal article

Journal

JCI Insight

Publication Date

22/02/2022

Keywords

COVID-19, NK cells, T cells, Vaccines