COVID-19, a significant global health threat, appears to be an immune-related disease. Failure of effective immune responses in initial stages of infection may contribute to development of cytokine storm and systemic inflammation with organ damage, leading to poor clinical outcomes. Disease severity and the emergence of new SARS-CoV-2 variants highlight the need for new preventative and therapeutic strategies to protect the immunocompromised population. Available data indicate that these people may benefit from adoptive transfer of allogeneic SARS-CoV-2-specific T cells isolated from convalescent individuals. This review first provides an insight into the mechanism of cytokine storm development, as it is directly related to the exhaustion of T cell population, essential for viral clearance and long-term antiviral immunity. Next, we describe virus-specific T lymphocytes as a promising and efficient approach for the treatment and prevention of severe COVID-19. Furthermore, other potential cell-based therapies, including natural killer cells, regulatory T cells and mesenchymal stem cells are mentioned. Additionally, we discuss fast and effective ways of producing clinical-grade antigen-specific T cells which can be cryopreserved and serve as an effective "off-the-shelf" approach for rapid treatment of SARS-CoV-2 infection in case of sudden patient deterioration.

Department of Laboratory Medicine Faculty of Health Care and Social Work Trnava University Univerzitne Namestie 1 918 43 Trnava Slovakia

Department of Oncology Faculty of Medicine and Dentistry Palacky University Olomouc University Hospital Olomouc Hnevotinska 976 3 77900 Olomouc Czech Republic

GAMMA ZA s r o Kollarova 8 911 01 Trencin Slovakia

Lambda Life a s Levocska 3617 3 851 01 Bratislava Slovakia

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