Which of the following are examples of effector cells?

• A. Memory T cells
• B. Macrophages
• C. Active T helper cells and Plasma cells
• D. Regulatory T cells

Answer: (C)

Effector cells are specialized immune cells that actively carry out responses to eliminate pathogens. Active T helper cells and plasma cells play crucial roles in this process.

Active T helper cells (also known as CD4+ T cells) are involved in orchestrating the immune response by activating other immune cells, such as B cells and cytotoxic T cells, enhancing the overall immune response. They release various cytokines that help regulate and direct immune reactions.

Plasma cells, on the other hand, are differentiated B cells that produce antibodies. These antibodies bind to specific antigens on pathogens, marking them for destruction by other components of the immune system and neutralizing their effects.

In contrast, memory T cells and regulatory T cells serve different functions. Memory T cells remain in the body after infection has resolved, ready to provide a faster and stronger response upon subsequent exposures to the same pathogen, but they do not actively combat pathogens during the initial immune response. Regulatory T cells play a vital role in maintaining immune tolerance and preventing autoimmune responses by inhibiting other immune cells, rather than acting directly against pathogens. Macrophages, while important for the immune response and capable of responding to pathogens, are not classified as effector cells in the same context as active T helper cells and