Innate Nonspecific Host Defenses (Microbiology)

Recall cards on the innate, nonspecific defenses of the host. Physical defenses: the skin and its layers, cell junctions, mucous membranes and the mucociliary escalator, flushing actions, and competitive exclusion by the resident microbiota. Chemical defenses: sebum and acidity, lysozyme and iron-binding proteins, antimicrobial peptides, acute-phase proteins, the complement system and its three activation pathways, cytokines, interferons, and inflammatory mediators. Cellular defenses: the formed elements of blood, granulocytes and agranulocytes, macrophages and dendritic cells, and natural killer cells. Pathogen recognition and phagocytosis: PAMPs and pattern recognition receptors, the phagosome and phagolysosome, and oxygen-dependent and oxygen-independent killing. And inflammation and fever: the signs of inflammation, pus and granulomas, pyrogens, and the resetting of the hypothalamic thermostat.