BIOC39H3 Lecture 10: Copy of BIOC39 - Lecture 10 Notes
Document Summary
Mechanisms of evasion and subversion of the immune system by pathogens. Subversion of the immune system: genetic variation, mutation and recombination, hiding: pathogens can hide from the immune system, sabotaging immune defense mechanisms. Genetic variating within a species can prevent long-term immunity: pathogens can invade the immune system by genetic variation of the surface structures of the pathogen, streptococcus pneumoniae is a very good example of this. It has capsular polysaccharides, in which there are multiple different strains of this pathogens. This antibody response is targeting various different epitopes on that h: person p the green antibody is providing the protection by binding at the site of the h that binds to the host cell protein. Original antigenic sin allows viral escape: original antigenic sin: phenomenon whereby first viral strain to infect constrains future response to other strains. Only memory b cells participate in the secondary immune response. This virus can then have rapid transmissibility and spread across the globe.