What is the primary role of humoral immunity?

The primary role of humoral immunity is to produce antibodies. This aspect of the immune system involves B cells, which are a type of lymphocyte that can differentiate into plasma cells, responsible for synthesizing and secreting antibodies into the bloodstream. These antibodies are critical for identifying and neutralizing pathogens such as bacteria and viruses. They work by binding to specific antigens on the surface of pathogens, marking them for destruction by other immune cells, or preventing them from entering and infecting host cells.

Humoral immunity is particularly effective against extracellular pathogens, those that reside outside of human cells, as opposed to intracellular pathogens like certain viruses. While T cells play a crucial role in cell-mediated immunity and cytotoxic activity, humoral immunity focuses primarily on the production of antibodies that target pathogens in the body fluids (or "humors"). This distinction is important in understanding the overall cooperation between different immune system branches in providing a comprehensive defense against infections.