what are the five roles of the immune system
kill or control pathogens control disease repair tissue damage organ development maintain organ integrity and function
how many known pathogens are there?
1400
direct mechanisms of tissue damage by pathogens
exotoxin production
endotoxin
direct cytopathic effect
indirect mechanisms of tissue damage by pathogens
immune complexes
anti-host antibody
cell-mediated immunity
what are the challenges that pathogens present the immune system with?
- diversity
- life cycle diversity
- diverse routes of infection
- rapid, targeted response over a broad domain
No single immune response types clears a pathogen? T/F
true
characteristics of recognition mechanisms of innate immunity
rapid response
fixed
limited number of specificities
constant during response
characteristics of recognition mechanisms of adaptive immunity
slow response days to weeks
variable
numerous highly selective specificities
improve during response
with out the innate response there is no adaptive immune system T/F
true
what are the primary lymphoid organs
bone marrow
thymus
what are the secondary lymphoid organs
lymph nodes
spleen
lymphatic system
organ-specific lymph node like tissues (tonsils)
where is the adaptive immune response initiated?
secondary lymphoid organs
where do naive and mature B and T cells reside?
secondary lymphoid organs
what the cells of the adaptive immune system
B cells
T cells
NK cells
what are the cells of the immune system
Macs Dendritic cells PMNs eosinophils basophils mast cells
what cells come from a monocyte
Macs
dendritic cells
what cells are granulocytes
neutrophils
eosinophils
basophils
mast cells
the innate immune cells come from what precursor?
common myeloid precursor
the adaptive immune cells come from what precursor ?
common lymphoid precursor
what cell has an adaptive precursor, but functions as an innate cell
NK cell
what do immune cells use to reach tissues?
cardiovascular and lymphatic systems
what is lymph?
interstitial fluid that drains into the lymphatic system
why does the lymphatic system drain unidirectional
unidirectional due to
- valves
- smooth muscle
- pressure gradient
- drains into venous system
what are the three stages of the generalized response to infection
- immediate innate
- induced innate
- adaptive
immediate innate immune response
0-4 hrs
minor tissue damage
-pathogen is recognized by soluble effector molecules and resident effector cells in infected tissue
induced innate immune response
4 hrs to 4 days
- activation of cells resident in the infected tissue
- inflammation, fever, acute phase response
adaptive immune response
4 days until pathogen defeat
- secondary lymphoid tissue close to infection is alerted of infection
- B and T cells are activated
- death or pathogen elimination is end result
immediate innate system components
barriers (skin)
antimicrobial peptides
complement
the induced innate immune response components(cells)
neutrophils monocytes (Macs and Dendritic) tissue resident cells but require activation -basophils -eosinophils -mast cells and NK cells
neutrophils
can only enter tissue due to an inflammatory response
-suicide cells
what are the three primary antigen presenting cells
dendritic cells
macrophage
B lymphocyte
antigen presentation activates lymphocytes
3 important things about this
- functionally infinite capacity for antigen recognition
- lymphocyte antigen specificity improves over time
- memory T and B cells
what is clonal selection and expansion
during infection lymphocytes with receptors that recognize the pathogen are activated
-proliferation and differentiation of pathogen-activated lymphocytes give effector cells that terminate the infection
what are the two types of T cells
CD 8 T cells cytotoxic cells
CD4 T cells helper cells
B cells
activated B cell forms numerous plasma cells
what cell secretes antibodies?
plasma cells
T/F antibodies are targeted against a single antigen?
True
