Phagocytes are key immune cells that recognize, internalize, and kill fungi.
Phagocytes, primarily macrophages and neutrophils, play a crucial role in defending the body against fungal infections. This process involves several steps:
-
Recognition: Phagocytes possess receptors that recognize specific molecules on the surface of fungi. These molecules can include components of the fungal cell wall, such as beta-glucans and chitin.
-
Internalization (Phagocytosis): Upon recognition, the phagocyte engulfs the fungus, forming a vesicle called a phagosome.
-
Killing within the Phagosome: The phagosome then fuses with lysosomes, organelles containing various enzymes and toxic substances. This fusion creates a phagolysosome. Within the phagolysosome, fungi are killed and degraded by:
- Enzymes: Lysozymes, proteases, and other enzymes break down fungal cell walls and internal structures.
- Reactive Oxygen Species (ROS): These toxic oxygen-containing molecules, such as superoxide and hydrogen peroxide, damage fungal cells.
- Nitric Oxide (NO): Another toxic molecule that can kill fungi.
- Antimicrobial Peptides: Defensins and other peptides disrupt fungal membranes.
In essence, the phagosome provides a contained environment where phagocytes can effectively kill and digest fungi, preventing the spread of infection.
