Cellular Immunity

Cellular immunity, also known as cell-mediated immunity, is a vital component of the immune system responsible for defending the body against intracellular pathogens, abnormal cells, and various threats. Key players in cellular immunity are T lymphocytes (T cells), which are crucial for orchestrating and executing immune responses. Cellular immunity involves the recognition of antigens presented by infected or abnormal cells. Antigen-presenting cells, such as macrophages and dendritic cells, process and present antigens to T cells. This interaction activates cytotoxic T cells, which directly attack and destroy infected or abnormal cells. Helper T cells play a regulatory role by coordinating immune responses and enhancing the activity of other immune cells. Major histocompatibility complex (MHC) molecules facilitate the presentation of antigens to T cells, ensuring specificity in the immune response. Cytokines, signaling proteins released by immune cells, modulate cellular immunity, influencing the activation, proliferation, and function of T cells. Cellular immunity is crucial for eliminating viruses, intracellular bacteria, and cancer cells. Dysfunction in cellular immunity can lead to increased susceptibility to infections and the development of certain cancers. Understanding cellular immunity is essential for vaccine development, immunotherapy, and managing various immune-related disorders.