BIOL 224 - Phagocytosis

Chemotaxis

Chemotaxis

release of bacterial byproducts attract phagocytes which extend pseudopods to catch the pathogen

Adhesion

pseudopods attach to PAMP

Ingestion

pseudopods retract and uptake pathogen; plasma membrane surrounds pathogen in an internalized vacuole is called a phagosome

Maturation

phagosome matures while trafficking through the cell and fuses with lysosomes into a phagolysosome

Lysis

lysosomes kill the pathogen with degradative enzymes including lysozyme, hydrolases, reactive oxygen metabolites (H2O2), nitric oxide, and superoxide anions

Elimination

phagolysosome fuses with the plasma membrane, releases debris and displays pathogens’ feature on their surface (important for activation of the adaptive immune system)

Phagocytosis

capturing, engulfing and digesting of foreign particles by phagocytes (e.g. macrophage, dendritic cells, neutrophil)