35. Intro to immunity part 4 Flashcards
tell me about the adaptive/acquired immmune response eg. time, cells etc.
slower response (days)
immunological memory
specific
B cells and T cells (Th and Tc)
where do B cells mature
bone marrow
what type of adaptive immune response are B cells important in
humoral immune response
what do B cells produce
antibodies
primary lymphoid tissue is what and what is it the site of
thymus and bone marrow
It is the site of leukocyte development
Secondary lymphoid tissue is what and what is it the site of
spleen, lymph nodes and MALT
site where adaptive immune response initiated
antibodies/immunoglobulins are produced by which cells
B cells and plasma cells
do antibodies bind specifically
yes
what are the 2 types of chains on an antibody
heavy and light
unlike B cells, T cells can only recognise …… antigens
peptide
what are the 2 types of chain on a T cell antigen receptor
alpha and beta
T cells can ONLY recognise peptide antigens presented to their TCRs by what molecules
MHC molecules
Major Histocompatibility Complex (MHC) molecules
Also referred to as …..
HLA (Human Leucocyte Antigens)
what are the 2 major classes of MHC
I and II
Class I MHC present to which T cells
CD8+T cells
Class II MHC present to which T cells
CD4+ T cells
where do T cells mature
Thymus
what are Naive T cells
never been activated
can macrophages present to Naive T cells
NO
- Naive T Cells and B Cells use the process of Transendothelial Migration to enter Lymph Nodes from where
High Endothelial Venules (HEV
TNFa stimulates Dendritic Cells to digest ingested proteins and display small peptides derived from these on their cell surface in complex aka what, to go an present to T cells
MHC-I and MHC-II molecules
Once activated, B cells clonally proliferate and differentiate into two different types of effector cells:
Plasma cells and memory B cells
after B cells are activated and proliferate into Plasma cells and memory B cells. what do those two do
- Plasma cells - produce and secrete soluble, antigen-specific antibodies
- Memory B cells - long lived cells that continue to circulate around the body
B cells need to receive how many signals to become fully activated and clonally proliferate in response to protein antigens
2
B cells need to receive two signals to become fully activated and clonally proliferate in response to protein antigens. what are the 2 signals
- Antigen
- ‘Helping’ signal (co-stimulation)
i think from a Th cell
I’m putting this in for extra info on the differentiation into plasma cells
B cells -> plasma cells -> antigen specific antibodies -> go to bind to pathogen
initially what low affinity antibody is secreted and then after B cells mutate they switch to high affinity antibody….?
IgM to IgG
what is it called when you change the antibody
class switching
B cells present MCH II to present to Tfh Cells. what are Tfc cells and what is their main function
T follicular helper cells which stimulate the B cells germinal centre to start to proliferate, differentiate and secrete antibodies
T follicular helper cells are a subset of what
CD4+ helper T cells
on an antibody, what is the top section comprised of
constant and variable regions
on an antibody, what is the bottom section comprised of
contains only constant regions
the constant regions on an antibody determines what
the class and mediates the immune interactions
the variable regions on an antibody determines what
the unique regions for binding specific antigens
the top part of the antibody structure is called
Fab
the bottom part of the antibody is called the
Fc
name the types of chains on an antibody and where
heavy and light - heavy is the bottom part and the inside bottom part of the top part. the light chain is the outside bottom part of the top part
which Ig is pentameric
IgM
what does IgM do
present in plasma and secretory fluids and cause Agglutination (Immune complex formation)and complement system activation - classical pathway
which class presents to CD8+
MCH I
which class presents to CD4+
MCH II
what is the most abundant antibody in the plasma
IgG
what Ig is second most abundent in the plasma
IgA
what antibody is the second to respond in an immune response
IgG
what is the function of IgG
dominant type during secondary response and foetal immunity (placental transfer), complement activation, NK cell activation, neutalisation
which antibody is in mucus and breast milk
IgA
describe the function of IgA
monomer in serum
dimer in secretory fluid
neonatal defense
in breast milk, mucus and tears
what does IgD do
monomer
B cell activation
describe the properties of IgE
monomer
least abundent
produced in allergic response
what antibody is produced in response to allergy
IgE
which antibodies are involved in opsinisation
IgG and IgM
CD4+ TH1 cells secrete
IL-2 and IFNy (cytokines)
macrophages secrete what IL
IL1
TH2 cells secrete what
IL 4,5 and 6 whic promotes B cell rolifertation
name a cytotoxic T cell
CD8+
what do CD8+ T cells do
activated by MHC I
kill virally infected cells
which cells kill protozoa
eosinophils
