Low CD3+ and CD4+ T cell levels predict need for ventilatory support and in-hospital mortality in patients with COVID-19: a retrospective cohort study. - Martínez EL; Moreno-Pérez Ó; Otero-Rodríguez S; García-Sevila R; Marco-de-la-Calle F; Sánchez-Martínez R; Merino-de-Lucas E; Ramos-Rincón JM (Frontiers in medicine, 2026)