Impaired Cytotoxic CD8 <sup>+</sup> T Cell Response in Elderly COVID-19 Patients
Jaana Westmeier, Krystallenia Paniskaki, Zehra Karaköse, Tanja Werner, Kathrin Sutter, Sebastian Dolff, Marvin Overbeck, Andreas Limmer, Jia Liu, Xin Zheng, Thorsten Brenner, Marc Moritz Berger, Oliver Witzke, Mirko Trilling, Mengji Lu, Dongliang Yang, Nina Babel, Timm H. Westhoff, Ulf Dittmer, Gennadiy Zelinskyy
Abstract
Cytotoxic T cells are responsible for the elimination of infected cells and are key players in the control of viruses. CD8 + T cells with an effector phenotype express cytotoxic molecules and are able to perform target cell killing. COVID-19 patients with a mild disease course were analyzed for the differentiation status and cytotoxic profile of CD8 + T cells. SARS-CoV-2 infection induced a vigorous cytotoxic CD8 + T cell response. However, this cytotoxic profile of T cells was not detected in COVID-19 patients over the age of 80 years. Thus, the absence of a cytotoxic response in elderly patients might be a possible reason for the more frequent severity of COVID-19 in this age group than in younger patients.