BIOL 4190 : Final Review
Document Summary
Cellular pathogenesis: attaches to ciliated columnar epithelial cells in the sinuses and airways, primary infection, tracheobronchial tree, nasopharynx, destroys cilia, which contributes to secondary bacterial infections. Cytokine storm: systemic inflammatory response syndrome *sirs, explains devastating nature, overreaction of the immune system, causing damage to the body, h5n1. Virus particle: enveloped, hemagglutinin (h) antigen glycoprotein spikes on surface, neuraminidase (n) antigen spikes, m2 ion channel protein, 8 segments of (-) ssrna. Influenza a life cycle: virus h binds to sialic acid present on glycoproteins of ciliated cells lining the sinuses and airways, endocytosis. Inside endosome, low ph from 7 to 5, causes conformational change. H protein: must be cleaved by cellular proteases for the virus to be infectious. Influenza exploits host nuclear-splicing machinery to splice viral mrna segments 7 and 8. Ns1 prevents nuclear export of cellular pre-mrnas, facilitating cap-snatching. Influenza a suppresses the interferon system in host cells.
