Differential Leukocytes Flashcards
NUCLEUS composition of neutrophils
3 to 5 lobes separated by filaments
CYTOPLASM color of neutrophils
Pink to tan with violet or lilac granules
Most common WBC in normal peripheral blood
Neutrophils
First phagocytes to reach infection sites
Neutrophils, followed by monocytes
Neutrophil movement
Zigzag pattern, becomes straight line in presence of chemotactic attractant
Progenitor shared by neutrophils and monocytes
GMP (Granulocyte monocyte progenitor)
Major cytokine for neutrophil production
G-CSF (granulocyte colony stimulating factor)
Neutrophil half-life in blood
Approximately 7 hours
Major functions of neutrophils
1) Phagocytosis and destruction of foreign material, 2) Generation of NETs, 3) Secretory function (source of cytokines and transcobalamin I)
NETs structure
Extracellular threadlike structures made of chains of nucleosomes from unfolded nuclear chromatin (DNA)
NETs composition
Contain enzymes from neutrophil granules
NETs function
Trap and kill gram-positive and gram-negative bacteria, as well as fungi
NETs production timing
Produced when neutrophils die as a result of antibacterial activity
Unique form of neutrophil cell death that results in the release of NETs
NETosis
Order of formation of neutrophil granules
Primary, Secondary, Tertiary, Secretory
Order of degranulation of neutrophil granules
Secretory, Tertiary, Secondary, Primary
Size of neutrophil granules (largest to smallest)
Primary, Secondary, Tertiary, Secretory
Primary (Azyrophilic) Granules contents
Myeloperoxidase (MPO), Acid β-glycerophosphatase, Lysozyme, Cathepsins, Defensins, Elastase, Proteinase-3
Primary (Azyrophilic) Granules formation stage
Promyelocyte stage
Primary (Azyrophilic) Granules release order
Last to be released (exocytosis)
Myeloperoxidase function
Bactericidal, fungicidal, and viricidal properties
Myeloperoxidase detection method
Flow cytometry and cytochemical staining
Lysozyme function
Antimicrobial enzyme (muramidase)
Secondary (Specific) Granules contents
β2-microglobulin, Collagenase, Gelatinase, Lactoferrin, Neutrophil gelatinase-associated lipocalin, Transcobalamin I, Lysozyme
Secondary (Specific) Granules formation stage
Myelocyte and metamyelocyte stages
Secondary (Specific) Granules release order
Third to be released
Lactoferrin function
Iron-binding protein, competes with bacteria for iron
Tertiary (Gelatinase) Granules contents
Gelatinase, Collagenase, Lysozyme, Acetyltransferase, β2-microglobulin
Tertiary (Gelatinase) Granules formation stage
Metamyelocyte and band stages
Tertiary (Gelatinase) Granules release order
Second to be released
Secretory Granules contents
CD11b/CD18, Vesicle-associated membrane-2, CD10, CD13, CD14, CD16, Cytochrome b558, Complement 1q receptor, Alkaline phosphatase, Complement receptor-1
Secretory Granules formation stage
Band and segmented neutrophil stages
Secretory Granules release order
First to be released (fuse to plasma membrane)
Alkaline phosphatase activity in WBCs
Only neutrophils have alkaline phosphatase activity
CD11b/CD18 function in neutrophils
Contributes to tight stationary binding between neutrophils and endothelial cells
Neutrophil pools in the bone marrow
Stem cell pool, Mitotic (Proliferation) pool, Storage (Maturation) pool
Mitotic (Proliferation) pool components
CMP (CFU-GEMMs), GMP, Myeloblast, Promyelocyte, Myelocyte (last mitotic stage)
Storage (Maturation) pool components
Metamyelocyte, Band, Segmented neutrophils
Hematopoietic stem cell marker
CD34
Peripheral blood neutrophil pools and their ratio
Circulating Neutrophil Pool (CNP) and Marginal Neutrophil Pool (MNP), 50:50 ratio
Location of Circulating Neutrophil Pool (CNP)
Found in plasma
Location of Marginal Neutrophil Pool (MNP)
Found adhering to blood vessels
Nucleus characteristics of eosinophils
Dark purple, usually has two lobes
Cytoplasm characteristics of eosinophils
Filled with large, spherical granules of uniform size that stain bright orange
Most specific cytokine for eosinophil lineage
IL-5
Functions of IL-5 in eosinophil lineage
Promotes terminal maturation, functional activation, and prevention of apoptosis