Which cells are activated by helper T-cells during an immune response to present antigens?

Helper T-cells play a crucial role in the adaptive immune response by activating other immune cells through the recognition of antigens presented by antigen-presenting cells (APCs). One of the primary functions of helper T-cells is to stimulate activated B-cells. When a B-cell encounters its specific antigen and presents it on its surface using major histocompatibility complex (MHC) class II molecules, the helper T-cell recognizes this interaction through its T-cell receptor (TCR).

This interaction is further enhanced when the helper T-cell secretes cytokines, which promote B-cell activation, proliferation, and differentiation into plasma cells capable of producing antibodies. The presence of antibodies is crucial for neutralizing pathogens and marking them for destruction.

While cytotoxic T-cells are also important in the immune response, they are primarily involved in directly killing infected or cancerous cells, not in the initial activation phase by helper T-cells. Red blood cells do not play a role in the immune response as they lack a nucleus and do not present antigens. Monocytes, although important in phagocytosing pathogens and eventually differentiating into macrophages or dendritic cells, are not the primary cells activated by helper T-cells in the context of presenting ant