1. Intro to Immune Syst Flashcards
cells of the immune system in humans are produced form what?
stem cells present in the bone
Inside the bone, there are _______ that secrete molecules to permit modulation of the cells produced from the hematopoetic stem cells.
osteoclasts, blood vessels, and stromal cells
what cells give rise to all of the cells of the immune system?
hematopoietic stem cells
the hematopoetic stem cells after division can produce plutipotent (multipotential) cells that can give rise to what two lineages?
myeloid or lymphoid
what cells come from the lymphoid progenitor cells?
NK cells, T lymphocytes, B lymphocytes
what cells come from the myeloid progenitor cells?
RBCs, neutrophils, basophils, eosinophils, platelets, macrophages/monocytes, mast cells, dendritic cells
what do hematopoietic stem cells divide into?
self renewing cell and mature cell (differentiated)
asymmetric after division
granules in both eosinophils and basophils are _____ in nature.
pro-inflammatory
basophils vs eosinophils re: infection type
basophils: immediate response (allergens)
eosinophils: parasitic infections
what are PMNs?
neutrophils
what do neutrophils do?
phagocytize
what are the communication cells between the myeloid lineage and lymphoid lineage?
dendritic cells
name the macrophage of these specific tissues:
- CNS
- liver
- lung
- bone
- microglial cells
- kupffer cells
- alveolar macrophages
- osteoclasts
B cells vs T cells - which secretes Abs?
B cells
what do helper T cells secrete?
cytokines
T cells secrete cytokines through the function of what?
receptors (need a receptor for a cytokine to work)
what are PRRs?
pattern recognition receptors
part of the innate immune system and what recognize microbes
multiple types:
- surface TLRs (sense cell wall characteristics like bacterial cell wall molecules, flagellin, etc)
- Endosomal TLRs (sense microbial nucleic acids/RNA in endosomes in an infected cell)
- cytoplasmic sensors (send bacterial peptidoglycans)
what do PRRs recognize?
pathogen-associated molecular patterns (PAMPs)
microbial associated molecular patterns (MAMPs)
Danger associated molecular patterns (DAMPs)
the result of a cell of the innate immune system recognizing a microbe is what?
production of IL-1, an activator of inflammation
____ is synthesized an expressed on endothelial surfaces so that neutrophils and monocytes can enter the interstitium.
e-selectin
what needs to be present for neutrophils and monocytes to enter the tissue via e-selectin?
IL1 and TNF
if the infection is not cleared by innate immune system, what triggers the adaptive response?
dendritic cells
dendritic cells bind microbes via receptors, and internalize and process peptides. the peptides are then expressed with what?
MHC (MHC class II) and the cell beocmes an antigen-presenting cell (APC)
in the presence of _____, APCs lose their adhesiveness (no longer stuck in epithelium) and begin to migrate.
IL-1 and TNF
migrating dendritic cells also increase expression of CCR7, which does what?
causes trafficking to the nearest lymph node
what happens to APCs as they travel to the nearest lymph node?
activation (upregulate molecs = COSTIMULATORY MOLECULES important in activating other cells once they get to the lymph node)
where in the lymph node do APCs first go?
T-cell zone
what do T cells need to be activated?
binding of APC AND costimulator molecules (B7 on APC binds CD28 on T cell)
How do T and B cells generate diversity?
gene rearrangement
V, D, J genes to make heavy chain
V and J for light chain
how do you differentiate between immune cells?
surface markers and Ab stains
what marker do all T cells have?
CD3+
what marker do all B cells have?
MHC II, CD19
what marker do all NK cells have?
Fc
which cells neutralize microbes, phagocytize, and activate complement?
B cells
what cells active macrophages, cause inflammation, and activate (proliferate and differentiate) T and B cells?
helper T cells
what do cytotoxic T cells do?
kill infected cells
what do regulatory T cells do?
suppress immune response
what do NK cells do?
kill infected cells
What do Th1 cells do?
make cytokines to help macrophages and CD8 responders
what do Th2 cells do?
make Abs to facilitate neutralization and stimulate other cells
what do Th17 cells do?
activate acute inflammation
what causes differentiation of CD4+ cells?
microenvironment at time of differentiation
how do we keep from responding to ourselves (re:immune response)?
tolerance
central: thymus/bone
- apoptosis
- change in receptors (receptor editing in B cells)
- Development of regulatory T lymphocytes (helper T cells only)
peripheral:
- anergy
- apoptosis
- suppression
what are the two major categories of malfunction of innate immunity?
innate immunity cells don’t work
or can have perfect cells that can’t get to the site of action (chemokin attractants not working properly)
are innate or adaptive immunity receptor specificity inherited in the genome?
innate only
are innate or adaptive immunity receptors expressed by all cells of a particular type (eg macrophages)?
innate
do innate or adaptive immunity receptors trigger immediate response?
innate
do innate or adaptive immunity receptors recognize broad classes of pathogen?
innate
do innate or adaptive immunity receptors interact witha range of molecular structures of a given type?
innate
are innate or adaptive immunity receptors encoded in multiple gene segments?
adaptive
do innate or adaptive immunity receptors require gene rearrangement?
adaptive
are innate or adaptive immunity receptors clonally distributed?
adaptive
are innate or adaptive immunity receptors able to discriminate between even closely related molecular structures?
adaptive
