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Hematology and oncology ` hematology and oncology—anatomy Hematology and oncology ` hematology and oncology—anatomy SectIon III 407

Erythrocytes Carry O to tissues and CO to lungs. Anucleate Eryth = red; cyte = cell.
2
2
A and lack organelles; biconcave A , with large Erythrocytosis = polycythemia =  Hct.
surface area-to-volume ratio for rapid gas Anisocytosis = varying sizes.
exchange. Life span of 120 days. Source of Poikilocytosis = varying shapes.
energy is glucose (90% used in glycolysis, 10%
used in HMP shunt). Membranes contain Reticulocyte = immature RBC; reflects
Cl /HCO antiporter, which allow RBCs to erythroid proliferation.
−
−
3
−
export HCO and transport CO from the Bluish color (polychromasia) on Wright-Giemsa
2
3
periphery to the lungs for elimination. stain of reticulocytes represents residual
ribosomal RNA.
Thrombocytes Involved in 1° hemostasis. Small cytoplasmic Thrombocytopenia or  platelet function results
(platelets) fragments A derived from megakaryocytes. in petechiae.
A Life span of 8–10 days. When activated by vWF receptor: GpIb.
endothelial injury, aggregate with other Fibrinogen receptor: GpIIb/IIIa.
platelets and interact with fibrinogen to form Thrombopoietin stimulates megakaryocyte
platelet plug. Contain dense granules (Ca , proliferation.
2+
ADP, Serotonin, Histamine; CASH) and α Alfa granules contain vWF, fibrinogen,
granules (vWF, fibrinogen, fibronectin, platelet fibronectin, platelet factor four.
factor 4). Approximately ⁄3 of platelet pool is
1
stored in the spleen.

Monocytes Found in blood, differentiate into macrophages Mono = one (nucleus); cyte = cell.

A in tissues.
Large, kidney-shaped nucleus A . Extensive
“frosted glass” cytoplasm.

Macrophages Phagocytose bacteria, cellular debris, and Macro = large; phage = eater.
A senescent RBCs. Long life in tissues. Macrophage naming varies by specific tissue
Differentiate from circulating blood type (eg, Kupffer cells in liver, histiocytes in
monocytes A . Activated by γ-interferon. connective tissue, Langerhans cells in skin,
Can function as antigen-presenting cell via osteoclasts in bone, microglial cells in brain).
MHC II. Important cellular component of Lipid A from bacterial LPS binds CD14 on
granulomas (eg, TB, sarcoidosis). macrophages to initiate septic shock.

FAS1_2019_10-HemaOncol.indd 407 11/7/19 5:04 PM