Adaptive Immunity Flashcards
What immune activation has three pathways, two of which are classical and alternative pathways?
complement system
Which adaptive immune cells produce antibodies?
b-cells
What induces the classical pathway of the complement system to begin?
antibodies that were created by the b-cells
What induces the alternative pathway of the complement system to begin?
spontaneously activated by the lack of inhibitors on the cell surface
What is the protein called when the alternative and classical pathways converge?
C3
What does C3 do?
cleaves proteins
coat the pathogen (opsonization)
stimulate inflammation
What cells release histamine?
MAST cells and basophils
What is the MAC (membrane attack complex) in the complement pathway?
a plug formed by multiple proteins that goes into the cell membrane of the bacterial cell and causes destruction of the cell
What does the liver do during a fever and why?
stores iron and zinc to keep it away from microorganisms because microorganisms can use the minerals to help them reproduce.
What are the two ‘arms” of the adaptive immune system?
humoral
cellular
What type of cells are part of the humoral (antibody-mediated) adaptive immune response?
b-cells
What type of cells are part of the cellular (cell-mediated) adaptive immune response?
t-cells
Are the antibodies created by the b-cells looking for a specific antigen?
yes
What type of adaptive immunity effects extracellular fluid?
humoral
what type of adaptive immunity effects intracellular tissue?
cellular
Do T-lymphocytes act directly by killing infected cells?
yes
What is a substance that mobilizes adaptive defenses and provokes an immune response?
antigen
Small molecule that is not immunogenic by itself but becomes immunogenic when it attaches to body proteins?
hapten
Can an antigen have multiple antigen binding sites?
yes
Can an antigen have multiple antibodies?
yes
Complex on the surface of every cell that lets immune cells know that the cell is one of our own.
MHC (major histocompatibilty complex) Proteins
Any cell that puts up an MHC protein complex with an antigen on it is called what?
APC (antigen-presenting cell)
How do antigen presenting cells (APC) link innate and adaptive immunity?
macrophage will gobble up invader and place a portion of it on the surface of the cell that will alert adaptive immune system of its presence.
where do all blood cells originate?
red bone marrow
Where do t-cells mature?
thymus
where do b-cells mature?
bone marrow
After t-cells and b-cells are formed, where do they migrate to?
primary lymphatic organs - thymus and bone marrow
What is immunocompetetent?
matured to recognize self antigens
after t-cells and b-cells mature, where do they go where they also may encounter antigens?
secondary lymphoid organs - lymphoid, spleen
what happens to t and b cells once they come in contact with an antigen?
they become activated, proliferate and differentiate
what are immunocompetent but not yet activated lymphocytes referred to as?
naive
what does self-tolerance refer to in b and t lymphocytes?
we are unresponsive to our own antigens. b and t cells are immunocompetent
What is the difference between positive selection and negative selection in T- cells?
positive selection: t cells recognize self MHC proteins. If they cannot identify MHC, they are destroyed.
negative selection: t cells recognize self MHC and they do not bind to self antigens displayed on MHC. Shows tolerance for self-antigens. If they bind to self antigens, they get destroyed.
What is the difference between positive selection and negative selection in b- cells?
successfully make antigen receptors on its surfact that can bind to MHCs
self-reactive ones die off
What does it mean once b and t naive cells encounter their antigens and they are selected? What is this called?
clonal selection
B and T cells that are immunocompetent but not yet exposed to an antigen that seed th esecondary lymphoid organs. What are they termed?
naive
After lymphocytes activate, proliferate, and becomes clones, what do they clone into and what do those clones do?
effector cells that fight the infection
memory cells that are able to respond next time we are exposed to the anitgen
What are the three major types of antigen-presenting cells (APCs)
dendritic
macrophage
b cells
Which type of APC phagocytizes pathogens and presents antigens to t cells? And is considered the most effective antigen presenting cell?
dendritic
which APC is widepsread in lymphoid organs and presents antigens to t cells?
macrophage
Which lymphocytes are phagocytes that present antigens to helper t cells?
b lymphocytes
Do T helper cells help activate B and T lymphocytes?
yes
What do b cells become once they become activated?
plasma cells
what cells actually produce antibodies once b cells are activated?
plasma cells
do all b cells become plasma cells or do some become memory cells?
some become memory cells
How long does it take for antibodies to respond to an infection at first exposure vs a second exposure when memory cells are activated?
first exposure 3-6 days
memory exposure - hours
What are two types of active humoral immunity on how we acquire the immunity?
naturally acquired
artificially acquired
what does it mean when we naturally acquire immunity?
we are actually exposed to a bacteria or virus
what does it mean to have artificially acquired immunity? are memory cells made?
vaccinated
yes
What is passive humoral immunity?
we are given the antibodies pre made
we have bypassed activation
b cells are not challenged by antigens
immunological memory does not occur
protection ends when antibodies degrade
where do naturally acquired passive antibodies come from?
mom via placenta or milk
how do we get artificially acquired passive humoral immunity?
injection of a serum that contains antibodies (gamma globulins/immunoglobulins (IG))
used in somethign like a snake bite because the venom would kill us so quickly.
Review this
What are two other names for antibodies?
immunoglobulins (IG)
globulins
Where are IGs found?
plasma of the blood
What are the 5 primary classes of IGs?
IgM
IgA
IgD
IgG
IgE
What is this part of the antigen called?
antigen binding site
What is this part of the antigen called?
heavy/long chains
What is this part of the antigen called?
light chains (smaller)
What is this part of the antigen called?
What does it determine?
What is it attached to?
stem/constant region
class if Ig
B cell
how many protein chains in an antigen?
4
Which antibody is made of 5 antibodies
first released upon infection
agglutinates (globs antigens all together)
IgM
Which antibody is made of 2 antibodies (monomer or dimer)
secretory
IgA
Which antibody is a monomer that functions as a b cell receptor?
IgD
Which antibody is a monomer that is the most abundant in the plasma
Late primary and secondary response
activates complement by classic pathway (antigen-antibody complex)
IgG
what is the antigen-antibody complex
activate complement by classic pathway
Which antibody is a monomer important with allergies and parisitic infections
causes mast cells and basophils to release histamine
IgE
what can antigen-antibody complexes do?
surround bacteria and neutralizes it
agglutination (globs infected cells together, inactivates them, makes them easier to phagocytize)
precipitation (attaches to small insoluble antigens, makes them soluble and then they precipitate out of solution)
activate classic compliment
What type of antigens are cellular immunity t cells fighting aginst?
intracellular antigens
Do t-cells directly kill the cells as oppose to developing antibodies?
yes
Two types of T Cells and what do they become?
CD4 - T-helper
CD8 - cytotoxic TC cells
What are the two MHC proteins important to T cell activation
Class I MHC proteins
Class II MHC proteins
Which class MHC protein is in all of our nucleated body cells
Class I
Which class MHC protein is in all of our antigen presenting cells (APC - dendritic, macrophages, b cells)
Class 2
Which class of MHC Proteins put out an endogenous antigen (self-antigen) or nonself antigen and binds to CD8 cells to tell it to kill the cell if it puts out a nonself antigen?
MHC Class I
Which class of MHC proteins find an antigen outside of the cell and engulf them and present an exondenous antigen to CD4 cells.
MHC Class II
What cells help activate T and B cells, induce T and B cell proliferation, their cytokines recruit other immune cells, confirms infections found by other cells
TH cells
Can the immune system exist without TH cells?
No
What are interleukins
stimulated by TH cells to signal B and T cell activation
Roles of cytotoxic TC cells
targets virus infected cellw with intracellular bacteria or parasites
can destroy all infected or abnormal cells
How do the TC cells destroy all abnormal or infected cells?
create perforins that create a pore in the cell, which releases a granzyme into the infected cell that induces apotosis (cell suicide)
