Download Leukocytes

MLAB 1415: HEMATOLOGY
Chapter 7: Leukocytes
Part Two
MONOCYTES
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Monopoiesis - the production and development
of monocytes, macrophages and their precursors.
Monocytes are produced in the bone marrow.
MONOCYTES
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Differentiation & maturation
 Produced from CFU-GM
 Can further differentiate into macrophages in
the tissues
Lifespan
 P.B ~ 8 hours
 Tissue
Regulation
 Production primarily regulated by cytokines
GM-CSF
 IL-3
 M-CSF
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MONOCYTES/MACROPHAGES
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Function
Protect the host from infectious agents or pathogens
via innate and adaptive immune response
 Phagocytosis
 Scavengers
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MATURATION OF THE MONOCYTIC SERIES
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Monoblast
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Size: 12-20µm
Cytoplasm
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Nucleus
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Blue, moderate amount
No granules
Round, oval or slightly folded
Eccentric
Reddish-purple
Chromatin fine and lacy
Vacuoles may be present
1-2 nucleoli
N:C ratio = 4:1
MATURATION OF THE MONOCYTIC SERIES
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Promonocyte (difficult to discern)
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Size: 12-20µm
Cytoplasm
Paler gray-blue and abundant
 “Bleb-like” pseudopods at periphery
 May contain fine red “dust-like” particles, azurophilic
granules
 Vacuoles may be present
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Nucleus
Round with chromatin creases or brain-like folding
 Central
 Reddish-purple with light clumping of chromatin
 0-2 nucleoli
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N:C ratio = 3:1 or 2:1
PROMONOCYTE
MATURATION OF THE MONOCYTIC SERIES
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Mature monocyte
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Normal in circulation: 2-9%
Size: 12-20µm
Cytoplasm
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Nucleus
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Pale gray-blue and abundant
Bleb-like pseudopods at periphery, variable shape
Numerous fine pale red dustlike granule scattered throughout
Vacuoles common
Increased folding or elongated
Central
Purplish with finer clumped chromatin
No nucleoli
N:C ratio = Variable
MONOCYTE
MONOCYTES…THINK….
Fine, Lacy Chromatin
Ground Glass Cytoplasm
MACROPHAGES
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Once the monocyte enters the tissues, it becomes a macrophage
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Size:15-80µm
Cytoplasm
 Gray-blue and abundant
 Ragged edges
 Vacuoles common
Nucleus
 Round with netlike appearance
 Purplish with finer clumped chromatin
 Nucleoli appear
MACROPHAGES IN VARIOUS TISSUES

Macrophage alias’
 Histiocytes
in the loose connective
tissue
 Kupffer cells in the liver
 Osteoclasts in the bone
 Microglial cells in the nervous
system
 Also scattered throughout the body
in all organ tissues (spleen, lung,
abdomen, etc)
MACROPHAGE
REFERENCES
http://winsorb.com/silica-gel.php
 http://image.bloodline.net/stories/storyReader$10
75
 MacKenzie, S., & Lynne, W. J. (2010). Clinical
Laboratory Hematology. Upper Saddle River:
Pearson Education, Inc.
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