T-Cell Immune Responses to SARS-CoV-2 Infection and Vaccination.

Area of Science:

• Immunology
• Virology
• Vaccinology

Background:

• The immune system combats SARS-CoV-2 through innate and adaptive responses.
• Immunological memory, established by the adaptive immune system, is fundamental to vaccine effectiveness.
• T cells play a critical role in mediating protective immunity against viral infections.

Purpose of the Study:

• To review current knowledge on the immune response to SARS-CoV-2 infection and vaccination.
• To focus on the role of T cells in establishing protective immunity.
• To discuss T-cell responses to variants and hybrid immunity.

Main Methods:

• Review of existing literature on SARS-CoV-2 immunology.
• Analysis of T-cell responses (CD4+ and CD8+) in COVID-19 patients and vaccine recipients.
• Discussion of T-cell cross-reactivity and responses to viral variants.

Main Results:

• Both infection and vaccination induce SARS-CoV-2-specific CD4+ and CD8+ T cells.
• Cross-reactive T cells are observed in patients with varying COVID-19 severity.
• Vaccine-induced T cells target viral Spike protein.

Conclusions:

• T cells are pivotal for protective immunity against SARS-CoV-2.
• Understanding T-cell responses is essential for optimizing COVID-19 vaccines.
• Strategies to enhance vaccine efficacy by modulating T-cell responses warrant further investigation.