AUTHOR=Gainullin Murat , Federico Lorenzo , Røkke Osen Julie , Chaban Viktoriia , Kared Hassen , Alirezaylavasani Amin , Lund-Johansen Fridtjof , Wildendahl Gull , Jacobsen Jon-Aksel , Sarwar Anjum Hina , Stratford Richard , Tennøe Simen , Malone Brandon , Clancy Trevor , Vaage John T. , Henriksen Kathleen , Wüsthoff Linda , Munthe Ludvig A. TITLE=People who use drugs show no increase in pre-existing T-cell cross-reactivity toward SARS-CoV-2 but develop a normal polyfunctional T-cell response after standard mRNA vaccination JOURNAL=Frontiers in Immunology VOLUME=14 YEAR=2024 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2023.1235210 DOI=10.3389/fimmu.2023.1235210 ISSN=1664-3224 ABSTRACT=

People who use drugs (PWUD) are at a high risk of contracting and developing severe coronavirus disease 2019 (COVID-19) and other infectious diseases due to their lifestyle, comorbidities, and the detrimental effects of opioids on cellular immunity. However, there is limited research on vaccine responses in PWUD, particularly regarding the role that T cells play in the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we show that before vaccination, PWUD did not exhibit an increased frequency of preexisting cross-reactive T cells to SARS-CoV-2 and that, despite the inhibitory effects that opioids have on T-cell immunity, standard vaccination can elicit robust polyfunctional CD4+ and CD8+ T-cell responses that were similar to those found in controls. Our findings indicate that vaccination stimulates an effective immune response in PWUD and highlight targeted vaccination as an essential public health instrument for the control of COVID-19 and other infectious diseases in this group of high-risk patients.