What is the main role of macrophages in the immune system?

Macrophages play a crucial role in the immune system primarily by engulfing and digesting pathogens and cellular debris through a process known as phagocytosis. These large white blood cells are essential for both innate and adaptive immunity. When macrophages encounter pathogens such as bacteria or viruses, they surround and ingest these invaders, breaking them down with enzymes. This action not only helps to clear infections but also serves to present antigens from the pathogens to other immune cells, thus initiating a more tailored immune response.

Moreover, macrophages are important in tissue homeostasis and repair, as they help remove dead cells and promote healing. Their ability to recognize and respond to a wide variety of pathogens makes them vital players in the body's first line of defense against infections.