PHYSL210A Lecture Notes - Lecture 13: Opsonin, Phagolysosome, Gram-Negative Bacteria
1 May 2019
School
Department
Course
Professor
Document Summary
Pattern recognition receptors: found in macrophages, some neutrophils and epithelial cells. Macrophages recognise some common patterns not found in self cells (lipopolysaccharide for gram negative and peptidoglycan for gram positive) Opsonisation: bacteria engulfs the bacteria, to increase efficiency of macrophages, the host body produces opsonin and put it on the surface of the bacteria. Wbc produces receptors on its surface that recognises these opsonin. Enhance the process of phagocytosis, by inviting more wbc to the site of infection. Opsonin: produced by host cell, speed up phagocytosis. Two types of opsonin: antibody and complement protein. Antibodies are made in the lymphoid tissue and complement proteins are made in the liver and found inactivated in the plasma. Bacteria enter body space and, on the surface, the opsonin are added. Macrophages are attracted to the site of infection. They have receptors that recognise complement proteins and antibody molecules, and engulfment takes place. Steps pf phagocytosis: macrophages extends out pseudopodia and engulf the bacteria.
