Overall Strategies Defense against complement Subversion of phagocytosis Subversion of immune responses BIOL 533 Lecture 8
BIOL 533 2 Lecture 8 Overall Strategies • Defense against complement • Subversion of phagocytosis • Subversion of immune responses
General Aspects Pathogen finds itself in hostile territory Host fights back and usually--but not always--wins o Host's defenses are interrelated and so are organisms countermeasures BIOL 533 Lecture 8
BIOL 533 3 Lecture 8 General Aspects • Pathogen finds itself in hostile territory – Host fights back and usually—but not always—wins • Host’s defenses are interrelated and so are organism’s countermeasures
General Aspects Given organism sometimes has numerous different virulence factors Does not have to harm tissue to be called virulence factor, although many do Have to determine precise role of each factor if a large number are involved Not always sure in vitro situation is same as in disease state BIOL 533 Lecture 8
BIOL 533 4 Lecture 8 General Aspects – Given organism sometimes has numerous different virulence factors • Does not have to harm tissue to be called virulence factor, although many do • Have to determine precise role of each factor if a large number are involved – Not always sure in vitro situation is same as in disease state
E Defense Against Complement Overall strategies Inhibit complement activation Mask activating substances paul IgA antibodies Cover up target of complement membrane attack complex BIOL 533 Lecture 8
BIOL 533 5 Lecture 8 Defense Against Complement • Overall strategies – Inhibit complement activation • Mask activating substances – Capsule – IgA antibodies – Cover up target of complement membrane attack complex
E Defense Against Complement Overall strategies, continued Appropriate inhibitor to activation to surface Inactivate complement chemotaxin C5a BIOL 533 Lecture 8
BIOL 533 6 Lecture 8 Defense Against Complement • Overall strategies, continued – Appropriate inhibitor to activation to surface – Inactivate complement chemotaxin C5a