Lecture notes Cells and Immunity Innate and Adaptive Immunity (BI2BC45)

21.01.20


L9 – Innate and Adaptive Immunity


Lecture:
 1st line of defense
o Commensal bacteria (normal)
 Compete with pathogens
 Change Ph
 Consume nutrients and secrete antimicrobial substances
o Skin
 Collagen
 Sweat w/salt, lysozymes and sebum
o Mucous membrane
 Epithelium and connective tissue
 Goblet cells make mucous
 Pathogens find it hard to penetrate the mucous
 Cilia that sweep the mucous and trapped
 pathogens / particles along
 Innate immunity
o 0-4 hours (initial)
o 4-96 hours (calling in other cells)
o Cells (phagocytes)
 Fast and non-specific
 Cell types
 Macrophages (sensing of pathogens)
o Every tissue (fixed or wandering) from monocyte
differentiation
o Signal other immune cells
o Phagocytosis (pseudopodia in pinocytosis)
o Egs of fixed macrophages in other tissues
 Osteoclasts
 Microglia
 Kupffer cells
o Recognize of cells: as non self, flagged bacteria (oxidization),
natural killer cells (recognize MHC class I cell if not
destruct)#
 Receptors for molecules that the body does not
present eg Gv-/glucan(yeast)
 Toll like receptors recognize PAMPS for response
 TLR1/2/6 are heterodimers
 Neutrophils (clear up pathogens)
o Circulate in blood for 7-10h prior to migrating into tissues
o Leukocytosis – clinical indicator
o Attracted to site of infection via chemotaxis factors secreted
by macrophages