Leukocytes - granulocytes

Question 1

Leukocyte are categorized as either

Answer 1

granulocytes or agranulocytes

Question 2

granulocytes

Answer 2

contain primary and secondary cytoplasmic granules

Question 3

how can leukocytes leave the blood stream

Answer 3

margination

pavementing (rolling and adhesion)

diapedesis

Question 4

functions of leukocytes

Answer 4

initiate immune response

defend body against pathogens

chemotaxis (signal WBC to help w/ infection and inflammation)

“true cells” have nucleus and organelles

Question 5

what signals WBC to respond by chemotaxis

Answer 5

cytokines

Question 6

Leukopenia

Answer 6

reduced number of circulating WBCs

can be due to bacterial / viral infection exposure to toxins

causes immune response

leukemia

Question 7

Leukocytosis

Answer 7

elevated WBC count

dehydration, allergy, infection

actively responding to infection producing lots of WBC

Question 8

hematopoietic stem cells

Answer 8

can self-renew

produce 2 committed precursor cells: myeloid stem cell & lymphoid stem cells

Question 9

why is self renewal of hematopoietic stem cells important

Answer 9

preserves the pool of stems cells and is critical for feeding the differentiation/maturation pathways

Question 10

Primary granules

Answer 10

stain blue-purple

azurophilic granules

Question 11

primary granules contain

Answer 11

lysosomal enzymes

Question 12

secondary granules contain

Answer 12

lysozyme

alkaline phosphatases

variable staining

Question 13

types of granulocytes

Answer 13

neutrophils

basophils

eosinophils

Question 14

Neutrophil

Answer 14

most abundant (60-70% of leukocytes)

6-7 hours -> up to 4 days in CT

multi-lobed nucleus

Question 15

Neutrophils act to

Answer 15

elimate opsonized bacteria

limit the extent of an inflammatory reaction in CT

Question 16

enzymes in primary granules

Answer 16

elastase

myeloperozidase

Question 17

enzymes in secondary granules

Answer 17

lysozymes

other proteases

Question 18

specific receptors for integrins (ICAM-1 and ICAM-2) enable what

Answer 18

antibacterial and homing function of neutrophil

Question 19

what WBC is the first to arrive in areas of tissue damage?

Answer 19

neutrophils

Question 20

neutrophils play an important role in

Answer 20

phagocytosis of bacteria and dead cells

Question 21

neutrophils are associated with what kind of inflammation

Answer 21

acute inflammation

Question 22

Neutrophils are the only leukocyte that sometimes have tertiary granules what enzyme do tertiary granules contain

Answer 22

gelatinase (breaks down collagen)

Question 23

Stab cells (band cells)

Answer 23

immature neutrophils

Question 24

respiratory burst

Answer 24

bacterial killing by generating hydrogen peroxide and hypochlorous acid

excessive respiratory burst puts cells in oxidative stress

function of neutrophils

Question 25

Eosinophils

Answer 25

reddish pink-orange granules

2-4% total leukocytes

2 lobe nucleus

circulation 2-6 hours

Tissue lifespan 8-12 hours

Question 26

Function of Eosinophils

Answer 26

play a role in parasitic infections

reducing the severity of allergic reactions

trigger bronchial asthma

Question 27

specific hydrolytic enzymes in eosinophils

Answer 27

histaminase

eosinophil peroxidase (EPO)

lysosomal enzymes

major basic protein (neutralizes heparin ; kills parasites)

Question 28

Eosinophils counteract ______ in hypersensitivity rxns

Answer 28

basophils

Question 29

True or False
Eosinophils have anti-parasitic function

Answer 29

True

Question 30

Eosinophils have affinity for what kind of complexes

Answer 30

Ag-Ab (antigen-antibody) complexes

these are destroyed by major basic protein in eosinophils

Question 31

Basophil

Answer 31

least numerous of the granulocytes

0.5-1% of the total number of leukocytes

blue-violet granules in cytoplasm

can leave circulation

**looks like a mast cell BUT DOES NOT give rise to mast cells

Question 32

Mast Cells

Answer 32

granules rich in histamine and heparin

derived from the myeloid stem cell - part of immune and neuroimmune systems

Question 33

mast cells are important in

Answer 33

allergy / anaphylaxis response

involved in wound healing

angiogenesis

immune tolerance

defense against pathogens

Question 34

Basophils and mast cells develop

Answer 34

from DIFFERENT hematopoietic lineages

Question 35

Specific basophil granules contain

Answer 35

hydrolytic enzymes

heparin sulfate (anticoagulant)

histamine (vasodilation and increase vascular permeability)

Leukotrienes - slow reacting substance of anaphylaxis ; smooth muscle contraction (asthma)

Question 36

basophils are used in

Answer 36

type 1 (immediate) hypersensitivity reactions

ex. asthma, hay fever, some allergic dermatitis

Question 37

anaphylaxis

Answer 37

caused by a severe hypersensitivity reaction

Question 38

True or False
Eosinophils counteract the effects of basophils

Answer 38

True