1-16 The Immune Response Flashcards
Lag/inductive/latent phase
period of time before antibody can be detected after initial exposure
Logarithmic/exponential phase
period when antibody production begins resulting in an exponential increase in antibody concentration
Steady state phase
peak antibody concentration is reached
decay/decline phase
antibody concentration falls followed by period of time where trace amount of antibody can be detected
what is the secondary response?
after initial exposure to antigen, resulting immune response remains primed to respond to that antigen
secondary response differs from primary response:
shorter lag higher rates of antibody synthesis higher peak of antibody titer longer persistence of antibody predominance of IgG class molecules higher affinity of antibody Requires less antigen to illicit response (more sesnsitive)
Toxin
molecule made by anything living
toxoid
Toxoid - take that toxin, make it non-toxic but still has same sequence/structure so that injection will cause an immune response and antibodies that will target the toxin.
why can’t you become immune to tetanus naturally?
The amount of tetanus toxin needed to form the immune response would kill you. Can’t become immune to tetanus toxin via the toxin itself.
descibe the tetanus vaccine
normally the toxin gets into cells, splits apart, and the active enzyme (A) reaches inhibitory neurons and causes extreme muscle contraction
tetanus + formaldehyde - A-B structure unable to break apart. B can no longer deliver A.
why do small botox injections work?
small enough to work but not small enough to cause “immunity” like a vaccine. this is why you can get multiple botox shots over time.
problem with not immunizing for tetanus?
someone comes into hospital after exposure, giving an immunization then will take 5-7 days to have an effect, too long of a period for the primary response to help them
antibodies initially produced will start out with ___ affinity that will be mosty Ig_
low affinity. will be mostly IgM. At some point, class switch to IgG and also higher affinity
What dictates the secondary response?
IgG. After second exposue, small IgM response will be the same, but IgG will be magnitudes greater
What do b-cells do? How do they work?
they make antibodies of a range of specificities
Clonal expansion
when right antigen comes into contact with a b-cell, the b-cell it begins to divide
how does affinity increase?
There may be several types of B-Cells that recongize different parts of the antigen moecule, some with high and some with low affinity.
Initially with concentration is high, all the different clones are active. As concentration drops due to immune response pulling the antigen into phagocytes, only the most sensitive b-cells will continue to “See” the antigen and continue to divide/make antibodies.
what paths might a b-cell take?
Some turn into plasma cell which can make large amount of antibody. Some stay as small lymphocytes and become memory cells in spleen/lymph nodes so then once secondary immune response occurs, the plasma cells may be gone that were making IgM and IgG for that molecule. Instead of having lots of b-cells that haven’t been selected for in any way. We start with lots of memory cells that make IgG.
primary vs secondary is based primary on what cell type?
memory b-cells
why do we still get a small IgM response after several exposures?
becuase we make so many b-cells every day that there will always be b-cells seeing the antigen for the “first time” and responding as such.
what happens when you remove the thymus neonatally?
B-Cells are fine but there is no immune response or a small IgM.
t-cell must see things for b-cells to do things.
how do T-Cell and B-Cells interact?
through multiple levels of secretion and multiple levels of cell contact. signals being sent both ways.
describe the control against autoimmune responses
t-cells are able to recongize self vs non-self., B-cells cannot do this
Class switch is dependant on? (class switch of what??)
T-Cells
