Physiology of Normal White Blood Cells Flashcards
Cytokines
low molecular weight, regulatory proteins/glycoproteins
messenger molecules, secreted by wbcs
assist in regulating the development of immune effector cells
act locally - paracrine signalling
Chemokines
induce directed chemotaxis in local responsive cells
act as attractants for leucocytes, recruit monocytes and neutrophils
e.g. MCP-1 - monocyte chemotactic protein 1
Inflammation
bacteria trigger macrophages to release cytokines and chemokines
vasodilation, migration
components: BVs, phagocytes, plasma proteins
Cell adhesion to endothelium
Initial Contact: P selectin and E selectin on endothelium recognised by oligosaccharides on leucocytes
Tighter adhesion: intercellular adhesion molecules (ICAMs) on endothelium recognised by integrins on leukocytes
Recognition
macrophage mannose receptor: ligand is conserved carbohydrate structure
scavenger receptor: ligand is anionic polymers, acetylated and oxidised LDL
toll like receptor: various ligands
Atherosclerosis - 3 areas of pathogenesis
endothelial cell dysfunction
inflammation
dysregulation of lipid metabolism
Damage of endothelium
production of chemokines and cytokines
recruitment of monocytes
development into foam macrophages/foam cells
Damage to endothelium & Deposition of lipids
potential exposure of collagen
platelet activation and coagulation