MIC 321 Lecture Notes - Lecture 22: Antigenic Drift, Gene Conversion, Herpes Labialis

• School: University of Miami
• Department: Microbiology and Immunology
• Course: MIC 321
• Professor: Williams Roger

Document Summary

2: antigenic evasion is changing antigens through mutation (drift) and antigenic shift or recombination, also have superantigens and subversion of immune response. 3: most pathogens never successful cause illness, most pathogens have genes dedicated to escaping or subverting our immune system. Ha and/or na encoded by avian flu = no protective immunity: gene conversion = change surface antigens. Gene in expression site excised and replaced by a copy of different but homologous gene: sleeping sickness. Genome encodes more than 1000 vsg (variable surface glycoproteins) Ab response to main vsg but not minority forms. Leads to dramatic cycling in # parasites in infected person b/c of chronic ab production and antigen clearance and then switching vsg: ab production leads to immune complexes and inflammation and neurological damage and coma = sleeping . 10: malaria does this too by switching antigens so no immunity to this new form. Bacteria also use gene conversion: salmonella (food poisoning) and neisseria gonorrhoeae.