Which immune cells are primarily involved in the response to viral infections?

The response to viral infections is primarily mediated by T lymphocytes. These cells play a crucial role in recognizing and eliminating cells that are infected with viruses. There are two main subsets of T lymphocytes involved in this process: CD8+ cytotoxic T cells, which directly kill virus-infected cells, and CD4+ helper T cells, which support other immune cells by producing cytokines that enhance the immune response.

While other immune cells, like B lymphocytes, natural killer (NK) cells, and macrophages, participate in the immune response to viral infections, T lymphocytes are fundamental for achieving viral clearance. B lymphocytes primarily produce antibodies, which can neutralize viruses, but they are not directly responsible for killing infected cells. NK cells are important for the initial response to viral infections and can kill infected cells as well but are not the primary players once T cells become activated. Macrophages contribute by phagocytosing infected cells and presenting viral antigens, but the specific targeting and elimination of virally infected cells is most effectively carried out by T lymphocytes. Thus, T lymphocytes are the cornerstone of the adaptive immune response to viruses.