7: The complement system Flashcards
what does the complement system consist of?
plasma proteins
where are the plasma proteins in the complement system produced?
the liver
what is the two goals of the complement system?
pathogen destruction and/or opsonization for phagocytosis
what are the 3 complement system pathways?
- classical pathway
- alternative pathway
- mannose-binding lectin pathway (MB Lectin)
c3b complement protein is what and does what?
opsonin, opsonization
how is the classical pathway triggered?
by antibodies bound to foreign antigens
c5a complement protein exerts what effect?
proinflammatory
c5a initiates the formation of a complex of complement proteins (C6,7,8,9) which compose the what?
Membrane attack complex (MAC)
what does the MAC do?
causes lysis of the infected cells
c5a is considered what?
chemokine
how is the alternative pathway initiated?
c3b binding on cell wall of pathogens (PAMPs)
which complement protein will always be activated?
c3
how is the MB lectin pathway initiated?
MB lectin (plasma protein) recognizes terminal mannose residues on microbial glycoproteins and glycolipids
MB lectin pathway is limited to what species?
microbes
how is the classical pathway initiated?
by a complement fixing antibody (IgM, IgG) bind antigen
