Cells of Immune System Flashcards
where do the cells of the immune system circulate
bloodstream
where do the cells of immune syst migrate
into tissues to detect foreign antigens
where do cells of immune syst accumulate
in specialised organs - develop and differentiate
what do all cells f immune syst derive form
haemopoetic stem cell
what can happen to haemopoetic stem cell
diff to
- common lymphoid precursor
- megakaryocyte
- granulocyte
- mast cell
- monocyte
what happens to a common lymphoid precursor
to T b or NK
what are the cells in the secondary lymphoid tissues
macrophage interdigitating and dendritic –> ANTIGEN PRESENTING CELLS
what happens to mgakaryocytehs
break to platelets used to clot blood
where are B cells from
bone marrow
where are T cells from
thymus
how many lymphocytes in blood
2 x 10(^6)/ml
what are lymphocytes involved in
recognition and effector functions toward antigens
what does the myeloid lineage of leucocytes compose of
granulocytes
monocytes
how many granulocytes in blood
9 x 10(^6)/ml
how long do granulocytes last
short lived (2-3 days)
what are the granulocytes and quantity
neutrophils (60-70%)
eosinophils (2-5%)
basophils (0.2%)
what are granulocytes involved in
effector functions toward antigens
how many monocytes in blood
1 x 10(^5)/ml
what are monocytes involved in
recognition and effector functions
remove particulate matter e.g. microbes or aged RBC
how are mast cells related to basophils
overlap in function, distinction of how they arise and where situated
where are mast cells found
in tissue whilst basophils in blood
what do granules of a neutrophil contain
lysosomes
secondary granules with lactoferrin and lysozyme
what are lysosomes
acid hydrolyses, myeloperoxidase, lysozyme, defensins
what is the nucleus like in a neutrophil
multi lobular
what do neutrophils do
adhere to endo cells lining blood vessels and squeeze between them to leave circulation and enter tissues - DIAPEDESIS
what are neutrophils predominant role
phagocytosis and destruction of pathogens
what does lysozyme do
break down cell walls
what does lactoferrin do
holds iron which can be used by cell later, microbes may need iron to grow
what si the nucleus like of eosinophils
bilobed nucleus
what does the crystalloid core of granule contain
major basic protein - potent toxin for helminth worms
cationic protein
derived neurotoxin
what happens when granules activated
opened
killing of large pathogens
how many basophils in circualtion
in very small nums
what triggers basophils
allergens to release the contents of their granules –> allergic response
what kind of nucleus does basophils have
segmented nucleus
large cytoplasmic granules
what do basophils contain
histamine and leukotrienes = allergic reaction
what is the nucleus like in a monocyte
takes up majority of cell cyto horseshoe shaped
what do lysosomes in monocyte contain
peroxidase and acid hydrolyses - imp for killing phagocytose microorganisms
where are kupffer cells found
in liver
where are mesangial cells found
kidney
where are alveolar macrophages found
lungs
where are microglial cells found
brain
where are sinus macrophages found
spleen, lymph nodes
where are serosal macrophages found
peritoneal cavity
how long do cells of mononuclear phagocyte system last
long lived (month or years)
what is major function of cells of mononuclear phagocyte system
disposal of microbes and dead body cells through phagocytosis
what are the accessory cells
platelets
antigen presenting cells
mast cells
endothelial cells
how many platelets in blood
5 x 10(^9).ml
what are platelets involved in
blood clotting and inflam
what do antigen presenting cells do
present antigen to T cells
what do mast cells do
structurally and functionally similar to basophils - in CT and close to mucosal surfaces
what do endothelial cells do
receptors recognise certain lymphocytes - control lymphocyte traffic and distribution
what do APC’s produce
cytokines and present antigens to t cells
what is key role of lymphocytes
role in cellular and humoral immunity
circulate body
where lymphocytes found
blood, lymph and specialised tissues
how long do lymphocytes last
long lived - memory cells
what does removal of lymphocytes result in
inability to produce antibody
inability to carry out cellular immunity
what does the spleen protect against
blood bourne antigens
what lymphoid organs react to antigens in lymph entering via skin/mucosal surface
lymph node
mesenteric lymph node
what lymphoid organs recat to antigens entering via mucosal surfaces
waldezyers ring
lymphoid nodules
peyeres patches
urogenital lymphoid tissue
what is differentiation controlled by
specific growth factors
what do the common lymphoid precursors diff to
25% - bone marrow B cells
60% - thymus T cells
15% - NK cells
what are monoclonal antibodies used for
study cells surfaces
what are cell markers sp to
one antigenic determinant
what do cell markers who when studying immune system
cluster of differentiation
what are CD marker on helper T cells
CD3
CD4
what are CD markers on cytotoxic T cells
CD3
CD8
what are CD markers on B cells
CD19
CD20
what are CD markers on NK cells
CD16
what is on all T cell surfaces of CD harder
CD3
why is specificity acquired in 1 lymphoid organs
education to distinguish self/non-self
when do B and T cells no function
when not activated
when does activation of Ba nd T cells occur
on meeting antigen binding to ti by antigen receptor
what do b cells diff to
plasma cells
have a lot of rER factories for making lg
what do t cells diff to
activated Tc no rER have granules containing proteins involved in killing
activated Th develop ability to prod GF’s or lymphokines
what does clonal expression produce
more activated cells and memory cells
gives more rapid, effective response
what are the secondary lymphoid organs
lymph nodes
spleen
MALT
what happens in secondary lymphoid organs
immune response occurs here
lymphocytes and APC brought together
what roles of pahogocytic cells derived cels from monocytes
phagocytosis
conc of antigen
processing and present antigen to t cells
secretion GF’s and cytokines
for an immune response need
cooperation between B, T, and APC
what does a immune response require
cell to cell contact
secretion of cytokines
