Cell-mediated immunity is primarily mediated by which cell type?

Cell-mediated immunity is primarily mediated by which cell type?

• A. B cells
• B. T-helper cells
• C. Plasma cells
• D. Dendritic cells

Answer: (B)

Cell-mediated immunity is driven by T lymphocytes. Helper T cells play a central coordinating role by recognizing antigen with MHC class II on antigen-presenting cells and releasing cytokines such as IL-2 and IFN-γ that activate cytotoxic T cells and macrophages. This orchestration enables the targeted killing of infected or abnormal cells, which is the hallmark of the cell-mediated response. B cells and their plasma cell descendants handle antibody production (humoral immunity), while dendritic cells primarily act as antigen-presenting cells to activate T cells rather than executing the effector response themselves.

Cell-mediated immunity is driven by T lymphocytes. Helper T cells play a central coordinating role by recognizing antigen with MHC class II on antigen-presenting cells and releasing cytokines such as IL-2 and IFN-γ that activate cytotoxic T cells and macrophages. This orchestration enables the targeted killing of infected or abnormal cells, which is the hallmark of the cell-mediated response. B cells and their plasma cell descendants handle antibody production (humoral immunity), while dendritic cells primarily act as antigen-presenting cells to activate T cells rather than executing the effector response themselves.