Figure 1.

Uptake of antigenic particles by immune phagocytes. (A) Dendritic cells (DC), macrophages (MF), and neutrophils (NE) of the immune system encounter particles with different physical properties (size, shape, rigidity, surface roughness). NE can release extracellular traps (NETs) for capturing large pathogens such as hyphal fungi. Macrophages can undergo reprogramming into pro-inflammatory (M1) or anti-inflammatory (M2) phenotypes. (B) Particles >0.5 µm are ingested by phagocytosis; smaller particles by endocytosis which can be clathrin or caveolin-mediated. The F-actin cytoskeleton is important for membrane wrapping at the phagocytic cup. Fusion with lysosomes containing lytic enzymes is the final step in endo/phagosomal maturation.