Lecture 1: Anatomy and Phys of Immune Systems

Question 1

all cells of the immune system come from one type of cell which is called_____

Answer 1

hematopoietic stem cells

Question 2

hematopoiesis is….

Answer 2

the process which cells differentiate from a common hematopoietic stem cell

Question 3

where does hematopoiesis occur?

Answer 3

the bone marrow in adults, liver in fetus

Question 4

what cells fall under the myeloid progenitor cell family?

Answer 4

neutrophils, basophils, eosinophils, monocytes, mast cells

Question 5

what cells fall under the lymphoid progenitor cell family?

Answer 5

B and T cells, and Natural killer cells

Question 6

what cells fall under the erythroid progenitor cell family?

Answer 6

erythrocytes and platelets

Question 7

the progenitor cells are located in the _____ and then travel to the _____ to differentiate further.

Answer 7

bone marrow, peripheral tissue

Question 8

how do we get so many different kinds of cells from one stem cell? Where does this differentiation happen?

Answer 8

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

Question 9

what molecule family induces myeloid lineage?

Answer 9

colony stimulating factors, CSFs

Question 10

_______ cells support hematopoietic cell growth and differentiation. what are some examples?

Answer 10

stromal

examples: fibroblasts, adipocytes, endotheial cells, macrophages

Question 11

for neutrophils, describe the:

• classification
• lineage
• nucleus appearance
• lifespan
• function
• mechanism of action

Answer 11

• 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)

Question 12

for Eosinophils, describe the:

classification:

lineage:

appearance:

lifespan:

function:

mechanism of action:

Answer 12

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

Question 13

once eosinophils are activated, they release what?

Answer 13

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

Question 14

for basophils, describe the:

classification:

lineage:

appearance:

lifespan:

function:

mechanism of action:

Answer 14

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

Question 15

for monocytes, describe the

classification:

lineage:

appearance:

lifespan:

function:

mechanism of action:

Answer 15

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

Question 16

for macrophages, describe the

classification:

lineage:

appearance:

lifespan:

function:

mechanism of action:

Answer 16

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

Question 17

macrophages release ______ after activation

Answer 17

cytokines and chemokines which promote inflammation

Question 18

for dendritic cells, describe the

classification:

lineage:

appearance:

lifespan:

function:

mechanism of action:

Answer 18

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

Question 19

after capturing an antigen by phagocytosis, a dendritic cell migrates to the ____ where they____

Answer 19

lymphoid organs, present the antigen to the T cells

Question 20

what is the difference between interstitial dendritic cells and interdigitating dendritic cells?

Answer 20

interstitial dendritic cells are in organs, and interdigitating dendritic cells are in secondary lymphoid tissue and thymus

Question 21

for mast cells, describe the

classification:

lineage:

location in health:

appearance:

lifespan:

function:

mechanism of action:

Answer 21

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

Question 22

in healthy status, mast cells do what?

Answer 22

they act as sentinels with granules so they cant act fast if needed

Question 23

for natural killer cells, descibre

classification:

lineage:

appearance:

location in health:

lifespan:

function:

mechanism of action:

Answer 23

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

Question 24

natural killer cells are known as ______ because _____

Answer 24

null lymphocytes

they have neither B or T markers

Question 25

natrual killer cells wil kill what kinds of cells? they also monitor the expression of \_\_\_\_

Answer 25

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)

Question 26

where do natural killer cells mature?

Answer 26

secondary lymphoid tissue

Question 27

lymphocytes originate in the ____ and then differentiate into ____ or \_\_\_\_

Answer 27

bone marrow B cells T cells

Question 28

T lymphocytes reside in the\_\_\_\_, and membrane T cell receptors are \_\_\_\_

Answer 28

paracortex of lymph node unique to each cell, only recognize 1 antigen

Question 29

activated T cells differentiate into \_\_\_\_\_.

Answer 29

specialized effecor cells, like helper T cells, cytotoxic t cells, regulatory t cells, and memory t cells

Question 30

what is th function of the following cells: helper t cells: cytotoxic t cells regulatory t cells memory t cells

Answer 30

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

Question 31

B cells reside in \_\_\_\_ they interact with ______ to become activated activated B cells mature into\_\_\_\_

Answer 31

follicles in cortex of lymph node, white pulp of spleen antigen T cells plasma cells (produce antibodies), and memory B cells

Question 32

plasma cells produce _____ and reside in \_\_\_. they are key players in the ____ immune system

Answer 32

antibodies tissues or lymphoid organs adaptive

Question 33

primary lymphoid organ examples: this is where lymphocytes \_\_\_\_ secondary lymphoid organ examples: this is where \_\_\_\_

Answer 33

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

Question 34

the bone marrow is the major site of

Answer 34

hematopoiesis

Question 35

B cells mature where?

Answer 35

bone marrow, some in peyers patches, in birds in the bursa of fabricus

Question 36

T cells develop in the ____ but then migrate to the ____ to mature

Answer 36

bone marrow, thymus

Question 37

B cells are found in the \_\_\_\_, T cells in the \_\_\_\_, and macrophages/dendritic cells in the ____ of lymph nodes and spleen

Answer 37

cortec paracortex medulla

Question 38

antigens enter lymph nodes via \_\_\_\_\_\_ naive lymphocytes enter the lymph node via\_\_\_\_

Answer 38

afferent lymphoid vessels high endothelial venules

Question 39

CD4+ T cells turn into\_\_\_ CD8+ T cells turn into\_\_\_

Answer 39

helper T cells (assist B cell differentiation) killer T cells (destroy virally infected cells)

Question 40

what is the main function of the spleen?

Answer 40

filters blood and traps blood borne pathogens (think systemic infection)

Question 41

the red pulp of the spleen is where\_\_\_ the white pulp is where\_\_\_

Answer 41

red blood cells are destroyed and recycles (RBCs are here and macripjages) it is a compartment for white blood cells, lymphocytes

Question 42

the mucusa associated lympohi tissue is associated with

Answer 42

tonsils, intestine (GALT), and branchial associated BALT

Question 43

what is GALT?

Answer 43

gut associated lymphoid tissue, Peyer's patch, usually near the ileum