IMMUNO 440 Lecture Notes - Lecture 1: Pattern Recognition Receptor, Pathogen-Associated Molecular Pattern, Antimicrobial Peptides
Document Summary
Chemical barriers include stomach acidity, secreted anti-microbial peptides. Cellular barriers include macrophages, neutrophils: activation of innate immune response occurs within minutes of pathogen recognition, rapid, does not generate immunologic memory, dependent upon germline encoded receptors recognizing structures common to many pathogens. Infections occur when pathogens evade/overwhelm innate defenses: results in localized infection, replication allows for potential dissemination. Steps of infections and protection: adherence to epithelium normal flora; local chemical factors; phagocytes (especially in lung) Local infection of tissues complement, cytokines, chemokines, phagocytes, nk cells; activation of macrophages, dendritic cells migrate to lymph nodes to initiate adaptive immunity: adaptive immunity infection cleared by specific antibody; t-cell dependent macrophage activation and cytotoxic t cells. Epithelial cell surfaces: first line of defense against infection: form tight junctions, barrier includes: Urogenital tract: pathogens most commonly cross epithelium by: May/may not lead to epithelial barrier damage and invasion: secrete mucus to prevent pathogen adherence (internal epithelium, pulmonary epithelium ciliated to expel pathogens f.
