Module 2: Normal Leukocytes (Monocytes/macrophages) Flashcards Preview

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Flashcards in Module 2: Normal Leukocytes (Monocytes/macrophages) Deck (20):
1

where do monocytes develop

bone marrow

2

stages of monocyte development (3)

monoblast
promonocyte
monocyte

3

monocytosis

increased monocyte count

4

monoblast characteristics

nucleus round, oval, slightly folded, fine thread-like red-purple chromatin, up to 5 nucleoli
Cytoplasm basophilic with grey coloration, no granules

5

promonocyte characteristics

nucleus folded, convoluted with red-purple chromatin, 0-5 nucleoli
cytoplasm is abundant, blue-grey, often has pseudopods and vacuoles

6

monocyte characteristics

nucleus indented, lacy chromatin
Cytoplasm abundant with very fine granules (frosted appearance) pseudopods and vacuoles common

7

normal rel%

2-9% in adults
higher in newborns and young infants

8

how long do monocytes circulate before moving to tissue

36hrs

9

monocyte

immature cell in blood circulation

10

macrophage

mature cell in tissue
Produce more lysozyme, increase in size
May be fixed or motile

11

Mononuclear phagocyte system (MPS)

another term for reticuloendothelial system (RE cells)
common name: macrophages

12

functions of macrophages (4)

phagocytic response to foreign antigens
immune recognition
iron metabolism
preservation of a youthful and healthy population of blood cells

13

Phagocytic response to foreign antigens

responds chemotactivally to inflammation, phagocytose and kill ingested microorganisms
Neutrophils provide first wave, then macrophages phagocytose dead neutrophils and body tissue

14

activation by cytokines from CD4 T cells (often INF-y)

activated macrophage gets bigger, stickier, aggressive
form folds in membrane to catch more antigens
secretes monokines (IL-1)

15

If any antigens survive lysozyme fusion

the organism is isolated and impounded inside Langhans giant cell granulomas
Formed by fusing together of many macrophages
"walls off" the harmful substance
often occurs in TB

16

How is activation of macrophages suppressed

secretion of prostaglandin E2 (PGE 2) from T4 cells and from macrophages themselves

17

Immune recognition

macrophages act as antigen presenting cells (APC) where they bind, engulf, digest, make antigen immunogenic and then present the processed antigen in association with HLA-D antigens on its membrane surface to T4 (CD4) and B lymphs for recognition

18

IL-1

Interleukin 1
best known monokine
essential in activation of CD4T cells by foreign antigens
stimulates hepatocytes to secrete acute phase proteins
stimulates GM-CSF production by other macrophages
Acts as endogenous pyrogen in inflammatory response

19

Secretory effector cells (functions of mono/macro secretions)

removal of old blood cells
stimulation of self-defense against tumor cells
modulation of immune function
regulation of hematopoiesis
stimulation of inflammatory reactions
removal of infection organisms by phagocytosis

20

Iron metabolism/ preserving healthy blood

removal of dead, defective, aged blood/tissue cells, denatured plasma proteins, lipids, activated coagulation factors and antigen-antibody complexes
SPLEEN AND LIVER SINUSOIDS
phagocytose and digest cells, retaining useful components