Blood Histology Flashcards
What is the function of blood? (3)
- delivery of nutrients and oxygen, transport of wastes and CO2
- delivery of hormones, regulatory substances, immune system cells
- maintenance of homeostasis: buffer, coagulation, thermoregulation
volume of RBCs in a blood sample
packed cell volume (PCV)
39-50% male
35-35% female
leukocytes and platelets in a centrifuge
buffy coat
- liquid extracellular material
- 90% H2O
- solvent for solutes (proteins and nutrients/electrolytes)
plasma
extracellular fluid component of blood that is present after coagulation process is complete, lacks clotting factors
serum
dervied from blood plasma, its electrolyte composition reflects that of blood plasma from which it is derived
interstitial fluid
- type of globulin
- functional immune system molecule
γ-globulin
- type of globulin
- maintain osmotic pressure within vascular walls, carrier proteins, coagulation factors
α-globulin and β-globulin
- main protein constituent (50%), made in liver
- exerts conc gradient between blood and extracellular fluid
- colloid osmotic pressure, pressure on vessel walls
- carrier protein for thyroxine, bilirubin, and barbiturates
albumin
- largest plasma protein, made in liver
- insoluble form is fibrin
- chains polymerize forming long fibers
- fibers become cross-linked and form an impermeable net, prevents blood loss
fibrinogen
- anucleate, devoid of organelles
- disc shaped, stain uniformly (eosin), area of central palor
- histologic ruler
- biconcave disc, flexible, increases SA 20-30% vs being spherical
- bind O2 and deliver to tissues, bind CO2 and remove from tissues
- lifespan: 120 days, ~1% removed each day from spleen, BM, liver
erythrocytes
dimeric, springy protein that forms a wheel-like meshwork and attach to membrane-bound hubs
spectrin
What is spectrin-actin skeleton connected to cell membrane by?
- ankyrin band 4.2 and band 3
- protein 4.1 and glycophorin A (GP)
- immature erythrocytes released from BM
- slighly less than 1% of circulating RBCs
- anucleate, but have mito, ribo, golgi elements, syn hemoglobin
- hallmark: RNA stains slightly basophillic (blue)
- enter circulation: lose polyribosomes and mature to erythrocytes within 48 hr
reticulocytes
- decreased hemoglobin levels
- most in the reduction of RBCs due to: hemorrhage, hemolytic _____, insufficient dietary intake of Fe, vitamin B12, or folic acid
- clinical sx: weakness, fatigue, frequent HAs, difficulty conc, dizziness, palor
anemia
- single point mutation (Glu > Val) β-globin chain of hemoglobin A (HbA) > sickle hemoglobin (HgS)
- erythrocytes become sickle-shaped at decreased O2 sat
- sickled RBCs = more fragile, vessel obstruction, break down ~20 days
- severe hemolytic anemia (HTC 18-30%) a/w reticulocytosis and hyperbilirubinemia
sickle-cell anemia
- inherited disorder caused by intrinsic defects in RBC cell membrane
- mutations in ANK1 are responsible for ~50% of cases
- apparent on smears as small, dark staining, and lacking central pallor
- sx: reticulocytosis, mild jaundice, splenomegaly
hereditary spherocytosis
- yellow appearance of sclera of eye and skin
- can be caused by destruction of circulating erythrocytes
- characteristic in many hemolytic anemias: inherited RBC defects, pathogen microbes, animal venoms, chemicals, drugs
- can occur in newborns because of inefficiency of liver
jaundice
Never
Let
Monkies
Eat Bananas
neutrophils (50-70%)
lymphocytes (20-40%)
monocytes (2-8%)
eosinophils (1-4%)
basophils (0.5-1%)
What is the peripheral blood leukocyte count influenced by? (4)
- cell number in precursor and storage pop (BM, thymus, circ, tissue)
- rate of release of cells from storage into circ
- proportion of cells adhering to vessel walls (marginal pool)
- rate of extravasation (blood into tissue)
- most numerous circulating WBC (50-70%)
- hallmark: segmented “multi-lobed” nucleus, general lack of cytoplasmic staining
- polymorphonuclear (PMN)
- function in acute inflammation and tissue injury
- pus :)
neutrophils
- type of neutrophil granule
- main active components: myeloperoxidase, neutrophil defensins
- actions: kill and degradation of engulfed microbes
primary granules
- type of neutrophil granule
- main active components: lysozyme, gelatinase, collagenase, lactoferrin, cathelicidins, transobalamin I
- actions: anti-microbial substances and tissue breakdown
specific secondary granules
- type of neutrophil granule
- main active components: gelatinase, adhesion molecules
- actions: matrix tissue breakdown (gel), fused into cell membrane (adh)
tertiary granules
- type of neutrophil granule
- main active components: membrane proteins; enzymes, alk phos, etc
- actions: bind to endothelium (prot), tissue breakdown (enzymes)
secretory granules
immature neutrophils with banded nucleus, caused by left shift
band cells
- similar size to neutrophils
- bi-lobed nucleus
- hallmark: abundance of large, acidophilic granules staining intensely pink/red
- 1-4% of circ WBCs
- granule histaminase: moderates effects of inflammatory vasoactive mediators
- phagocytose antigen-ab complexes
- increased counts occur w/ allergies and parastic worms
- mediate chronic inflammation (lung tissue in asthmatics)
eosinophils
- hallmark: specific granules that stain intensely purple/blue
- nucleus usually obscurred by granules
- same size as neutrophils
- least numerous <1% of WBCs
- release vasoactive agents (heparin, histamine) and supplment mast function
- severe vascular disturbances a/w type 1 hypersensitivty rxns and anaphylaxis (binds antigen-IgE complex of plasma cells, triggers exocytosis of granules)
basophils
- 2-8% of circulating WBC
- hallmark: intensely staining, spherical nucleus w/ thin, pale blue rim of cytoplasm
- main functional cells of immune system
- non terminally deferentiated T cells, B cells > plasma, NK cells
lymphocytes
- largest of WBCs
- 2-8% of circulating WBCs
- hallmark: indented, heart-shaped nucleus w/ paler cytoplasm, contains small, azurophilic granules
- precursor cell of macrophages: osteoclasts, Kupffer cells (liver), microglia (brain); macrophages (connective tissue, LNs, spleen, BM)
- differentiate in reponse to inflammation: monocyte leaves vasculature > macrophage > phagocytosis
monocytes
- derived from megakaryocyte: large polyploid cell in bone marrow
- small bits of cytoplasm are broken off, circulate as discoid structures w/ life span of ~10 days
- hallmark: small, membrane bound, cytoplasmic fragments
- contain granules that release platelet-specific proteins, function in controlling blood loss, hemostasis
- bind to, coat, and plug damaged vessel walls and help activate blood clotting cascade
thrombocytes