Lecture 1: Anatomy and Phys of Immune Systems Flashcards
all cells of the immune system come from one type of cell which is called_____
hematopoietic stem cells
hematopoiesis is….
the process which cells differentiate from a common hematopoietic stem cell
where does hematopoiesis occur?
the bone marrow in adults, liver in fetus
what cells fall under the myeloid progenitor cell family?
neutrophils, basophils, eosinophils, monocytes, mast cells
what cells fall under the lymphoid progenitor cell family?
B and T cells, and Natural killer cells
what cells fall under the erythroid progenitor cell family?
erythrocytes and platelets
the progenitor cells are located in the _____ and then travel to the _____ to differentiate further.
bone marrow, peripheral tissue
how do we get so many different kinds of cells from one stem cell? Where does this differentiation happen?
different mixes of growth factors and cytokines will cause the differentiation of different types of cells. this mix of things occurs in the bone marrow
what molecule family induces myeloid lineage?
colony stimulating factors, CSFs
_______ cells support hematopoietic cell growth and differentiation. what are some examples?
stromal
examples: fibroblasts, adipocytes, endotheial cells, macrophages
for neutrophils, describe the:
- classification
- lineage
- nucleus appearance
- lifespan
- function
- mechanism of action
- classification: granulocyte
- lineage: myeloid
- nucleus appearance: multilobed
- lifespan: 48-72 hours, short
- function: antimicrobial in acute bacteria infection
- mechanism of action: phagocytosis and degranulation of antimicrobial peptides and toxic metabolites, NET formation (extracellular traps for bacteria)
for Eosinophils, describe the:
classification:
lineage:
appearance:
lifespan:
function:
mechanism of action:
classification: granulocyte
lineage: myeloid
appearance: bi-lobed, granules, red
lifespan: days to weeks
function: antiparasitic effectors, especially helminth infection
mechanism of action: powerful degranulation, limited phagocytosis
once eosinophils are activated, they release what?
preformed and stored toxic molecules, such as:
major basic protein (MBP)
eosinophilic cationic protein
eosinophil derived neurotoxin
these cause severe tissue damage and alter the skin/membrane of a nematode
for basophils, describe the:
classification:
lineage:
appearance:
lifespan:
function:
mechanism of action:
classification: granulocyte
lineage: myeloid
appearance: bi-lobed, blue-purple cytoplasm
lifespan: days
function: mediator of inflammation
mechanism of action: degranulation, synthesis and release of inflammatory mediators
for monocytes, describe the
classification:
lineage:
appearance:
lifespan:
function:
mechanism of action:
classification: mononuclear phagocyte
lineage: myeloid
appearance: large indented nucleus, pale blue-grey cytoplasm
lifespan: days
function: precursors to macrophages and dendritic cells
mechanism of action: antimicrobial function in the blood, still undifferentiated
for macrophages, describe the
classification:
lineage:
appearance:
lifespan:
function:
mechanism of action:
classification: mononuclear phagocytic cell
lineage: myeloid
appearance: rounded nucleus, clear cytoplasm, irregular cell shape
lifespan: months
function: phagocytosis, antimicrobial activity, some antigen presentation, tissue remodelling
mechanism of action: detection of threat, release inflammatory mediators, phagocytosis, endocytosis
macrophages release ______ after activation
cytokines and chemokines which promote inflammation
for dendritic cells, describe the
classification:
lineage:
appearance:
lifespan:
function:
mechanism of action:
classification: sentinel cell/anigen presenting cell
lineage: myeloid
appearance: round nucleus, clear cytoplasm, branched projections
lifespan: months
function: antigen presentation
mechanism of action: release of inflammatory mediators and endocytosis
after capturing an antigen by phagocytosis, a dendritic cell migrates to the ____ where they____
lymphoid organs, present the antigen to the T cells
what is the difference between interstitial dendritic cells and interdigitating dendritic cells?
interstitial dendritic cells are in organs, and interdigitating dendritic cells are in secondary lymphoid tissue and thymus
for mast cells, describe the
classification:
lineage:
location in health:
appearance:
lifespan:
function:
mechanism of action:
classification: NA
lineage: myeloid
location in health: connective tissue and lamina propria of the mucousa
appearance: round nucleus, cytoplasm packed with granules
lifespan: weeks to months
function: mediator of inflammation and allergy
mechanism of action: release of inflammatory mediators via degranulation or synthesis of lipid mediators and cytokines
in healthy status, mast cells do what?
they act as sentinels with granules so they cant act fast if needed
for natural killer cells, descibre
classification:
lineage:
appearance:
location in health:
lifespan:
function:
mechanism of action:
classification: lymphocyte
lineage: lymphoid
appearance: round nucelus
location in health: blood, spleen
lifespan: weeks to months
function: destruction of virally infected of abnormal host cells
mechanism of action: release of cytotoxic granules
natural killer cells are known as ______ because _____
null lymphocytes
they have neither B or T markers
natrual killer cells wil kill what kinds of cells?
they also monitor the expression of ____
tumour cells or virally infected cells
MHC complex, cells with low or altered MHC will be killed (apoptosis induced or release of enzymes that punch holes in the cell membrane)
where do natural killer cells mature?
secondary lymphoid tissue
lymphocytes originate in the ____ and then differentiate into ____ or ____
bone marrow
B cells
T cells
T lymphocytes reside in the____, and membrane T cell receptors are ____
paracortex of lymph node
unique to each cell, only recognize 1 antigen
activated T cells differentiate into _____.
specialized effecor cells, like helper T cells, cytotoxic t cells, regulatory t cells, and memory t cells
what is th function of the following cells:
helper t cells:
cytotoxic t cells
regulatory t cells
memory t cells
helper t cells: activate B cells and macrophages
cytotoxic t cells: kill virus-infected cell and cancer cells, like NKCs but more powerful?
regulatory t cells: diminish activation and imflammation
memory t cells: keep antigen presentation for years so recognition is faster the second time
B cells reside in ____
they interact with ______ to become activated
activated B cells mature into____
follicles in cortex of lymph node, white pulp of spleen
antigen T cells
plasma cells (produce antibodies), and memory B cells
plasma cells produce _____ and reside in ___. they are key players in the ____ immune system
antibodies
tissues or lymphoid organs
adaptive
primary lymphoid organ examples:
this is where lymphocytes ____
secondary lymphoid organ examples:
this is where ____
thymus, bone marrow, bursa of fabricus (birds)
develop and mature
lymph nodes, spleen, mucosa associated lymphoid tissue (MALT)
antigens are trapped and mature lymphocytes interact
the bone marrow is the major site of
hematopoiesis
B cells mature where?
bone marrow, some in peyers patches, in birds in the bursa of fabricus
T cells develop in the ____ but then migrate to the ____ to mature
bone marrow, thymus
B cells are found in the ____, T cells in the ____, and macrophages/dendritic cells in the ____ of lymph nodes and spleen
cortec
paracortex
medulla
antigens enter lymph nodes via ______
naive lymphocytes enter the lymph node via____
afferent lymphoid vessels
high endothelial venules
CD4+ T cells turn into___
CD8+ T cells turn into___
helper T cells (assist B cell differentiation)
killer T cells (destroy virally infected cells)
what is the main function of the spleen?
filters blood and traps blood borne pathogens (think systemic infection)
the red pulp of the spleen is where___
the white pulp is where___
red blood cells are destroyed and recycles (RBCs are here and macripjages)
it is a compartment for white blood cells, lymphocytes
the mucusa associated lympohi tissue is associated with
tonsils, intestine (GALT), and branchial associated BALT
what is GALT?
gut associated lymphoid tissue, Peyer’s patch, usually near the ileum
