T cell responses to SARS-CoV-2.

This chapter provides a comprehensive analysis of T cell responses in COVID-19, focusing on T cell differentiation, specificity, and functional characteristics during SARS-CoV-2 infection. The differentiation of T cells in COVID-19 is explored, highlighting the key factors that influence T cell fate and effector functions. The immunology of the spike protein, a critical component of SARS-CoV-2, is discussed in detail, emphasizing its role in driving T-cell responses. The cellular immune responses against SARS-CoV-2 during acute infection are examined, including the specificity, phenotype, and functional attributes of SARS-CoV-2-specific T-cell responses. Furthermore, the chapter explores T-cell cross-recognition against other human coronaviruses (HCoVs) and the mechanisms of immune regulation mediated by spike proteins. This includes the induction of regulation through the innate immune system, the activation of self-spike protein-cross-reactive regulatory T cells, and the impact of self-tolerance on the regulation of spike proteins. The chapter investigates T cell responses to self-spike proteins and their implications in disease. The role of spike proteins as immunological targets in the context of COVID-19 is examined, shedding light on potential therapeutic interventions and clinical trials in autoimmune diseases. In conclusion, this chapter provides a comprehensive understanding of T cell responses in COVID-19, highlighting their differentiation, immune regulation, and clinical implications. This knowledge contributes to the development of targeted immunotherapies, vaccine strategies, and diagnostic approaches for COVID-19 and other related diseases.