ACTUAL QUESTIONS AND DEFINITIVE SOLUTIONS
Which two types of antibodies can activate complement?
Igm and igg
What happens when igm binds microbes to allow for
complement activation?
It changes shape
Which complement protein will bind to igm?
C1q
Opsonization (and the complement protein involved)
C3b; coats microbes to allow them to be easily recognized by
phagocytes, c3b has a binding side for phagocyte receptors
Which enzyme is responsible for cleaving c3b into c5b and
c5a?
C5 convertase
,Spontaneous pathway complement activation
The microbial surface itself activates complement
What kind of molecule do lectins bind to?
Sugars
Adaptive immune cells are also called
Lymphocytes
Which kind of lymphocyte is involved in humoral immunity
B cell
Which kind of lymphocyte is involved in cell-mediated
immunity
T cells
What kind of cell produce antibodies
B cells
,Humoral immunity is the principle defense mechanism against
what type of infections
Extracellular microbes
What are the 4 major functions of antibodies
Neutralization, opsonization, complement activation, direct
killing through antibody-dependent cellular cytotoxicity (adcc)
Neutralization
When antibodies bind to antigens (e.g. Virus, toxin) and block
them from binding to cellular receptors and making us sick
Antibody dependent cellular cytotoxicity
Antibodies will bind to cell surface proteins on infected cells to
recruit natural killer cells that will kill the cell
Fab region of antibody
The variable portion of the antibody that contains the antigen
binding site (2 arms)
Fc region of antibody
, The constant portion of the antibody that may bind to immune
cell receptors on macrophages, neutrophils, and mast cells
(during opsonization)
Igg antibody (structure and function)
A monomer; most common ig; "workhorse" of humoral
immunity
Igd antibody (structure and function)
A monomer; function unknown
Ige antibody (structure and function)
A monomer; involved in allergy and response to helminths
(worms)
Iga antibody (structure and function)
A dimer (4 binding sites) joined by j chains; protease-resistant;
functions in the gut
Igm antibody (structure and function)
A pentamer (10 binding sites) joined by j chains; low affinity but
high avidity