Complement system Flashcards
Charles Bordet and P. Harlech experiment
they tested serums ability to neutralize a pathogen at 37 degrees and 57 degrees and noticed that at 37 degrees the pathogens would get lysed while at 57 they would only get agglutinated, leading to the conclusion that there was something else involved
General idea about complement system and main function
Effector of innate and adaptive immune system, main function is cell lysis through pore formation, other functions include being chemical signals
Name all functions of complement system
Cell lysis, cellular activation and anaphylaxis, immunocomplex deactivation in Liver and spleen, Opsonization, B cell activation, promotion of phagocytosis, chemotaxis and inflammation
C4B2b complex is also known as
C3 convertase
What does it do in the spleen and liver
Deactivate immunocomplexes moving through the blood
How many C9 subunits used in pore formation
10-16 c9 units penetrate membrane forming a pore leading to lysis of pathogen
Steps in pore formation
C5 cleaved by c5 convertase , C6 and C7 join followed by C8 triggering C9 pore assembly
Name for pore complex
MAC=Membrane attack complex
What are MASPs and where are they involved
Proteolytic enymes involved in first step of the lectin complement pathway
complement peptide that carries out opsonization
C3d final product of C3 degradation, C3b
what stabilizes C3bBb complex in alternative pathway
Properdin
What triggers Alternative pathway
Membrane lipid carbs on bacteria and fungi
What complex is the C5 convertase in classical pathway, and the C3 convertase?
C5 convertase–4b2a3b and C3-convertase
what two factors mediate B cell activation by the complement system
CR2 receptors interacting with C3d bound to pathogen and interaction of B cell IgM with antigen on pathogen
how do anaphylatoxins indirectly aid in adaptive immune response
Recruit myeloid cells, promote phagocytosis etc. by increasing immune flow they indirectly increase the speed of antigen presentation
