ClinLab Block 4 Flashcards
How much blood do males and females have?
M- 5-6L
F- 4-5L
What are the three general functions of blood?
Transportation
Regulation
Protection
What are the three parts of centrifuged blood?
Plasma- 55% water liquid extracellular matrix
REBs- 45%
Buffy coat- WBCs and platelets
What are the percentages of WBCs in blood volume?
Neutrophils: 60-70% Lymphocytes: 20-25% Monocytes: 3-8% Eosinophils: 2-4% Basophils: 0.5-1%
What are the two functions of bone marrow?
Supply peripheral circulation with mature cells
Increase production if hematological conditions warrant
How do cells enter the blood stream?
Define Polychromasia
Sinusoids
Immature cells referred to as reticulocytes and staines w/ supra vital stain
Formed elements do not divide once they leave the red bone marrow with what exception?
Lymphocytes
What is the normal Erythroid/Granulocyte ratio?
What causes the ratio to increase?
1 : 3
Anemia
Define Stem Cell Pools
Stems cells with high self-renewal capacity and committed CFUs
Define Bone Marrow Pools
Cells stored for later release into peripheral circulation
Define Peripheral blood pools
Functional cells and storage forms of platelets and granulocytes (marginating granulocytes)
Define Hematopoieses
Production, development, differentiation, and maturation of ALL blood cells
What are the fates of myeloid and lymphoid stem cells?
M- give rise to RBCs, platelets, monocytes, neutrophils, eosinophils and basophils
L- lymphocytes
Hemopoietic growth factors regulate ? and ?
What stimulates each and where is the factor made?
Differentiation and Proliferation
Epo- RBCs, kidney
Thrombo- platelets, liver
CSFs and Interleukins- WBCs
Where is Erythropoietin and Thrombopoietin synthesized what cell do they exert their effect on?
E- kidney, RBCs
T- liver, platelets
Define Cytokines, Interleukins, and CSFs
Chemical signals responsible for promoting a specific lineage of cell
What is that pathway of events that causes increased production of blood cells?
Receptors: Dec O2 sensing in kidney
Input: inc erythropoietin released in blood
Control Center: proerythroblasts in red bone marrow mature into reticulocytes
Output: Reticulocytes enter circulation
Effector: larger number of RBCs in blood and sensed by kidneys
What stimulates the release of erythropoietin and what happens in the developmental steps?
Hypoxia
Red marrow w/ proerythroblasts who eject nucleus and become reticulocytes who develop into RBCs in 1-2days
What parts of erythropoietin cell development are erythropoietin or iron dependent?
Fe- Erytheroblasts and Reticulocytes
Eryth- everything before and including erythroblasts
What is Hgb composed of?
2 alpha and 2 beta chains
Oxygen affinity to Hgb A primarily depends on what three factors?
Temp
pH
2,3-BPG concentration
Difference between Ferrous and Ferric Iron
Which process is required for Fe metabolism?
Ous- 2+ reduced
Ic- 3+ oxidized
Redox change
How is Fe transported in the blood?
As Hgb, can not be exchanged
Transferrin bound
What makes up the Heme structure and what is it called?
If Fe is added to it what does it become?
C H N
Protoporphyrin IX
Fe2 added= Ferroprotoporphyrin
What types of Hgb are formed in a yolk sac?
What are the four types of Hgb chains that can be formed in fetus and adults?
Epsilon and Zeta
A B G D
Normal Hgb has _ globin chains
What makes up Hgb F and where is it seen?
4
A2G2- predominant formed during liver/marrow erythropoiesis in fetus
All adult normal Hgb is formed as ?
Tetramers
HbA- A2B2
HbA2- A2D2
HbF- A2G2
What are the two hemoglobinopathies listed
Thalassemia: Underproduction of normal globin proteins/lack of synthesis of chains resulting frommutated genes
Qualitative Disorders: Sickle cell dz resulting from point mutation of glutamic acid to valin in globin gene
How long do RBCs live for and where are they broken down?
120 days
Spleen and liver
RBCs that are broken down end up in what three things with what end fates?
Globins aa- reused
Fe- reused
Non-iron heme- urobilin in urine or brown stercobilin in feces
RBCs broken down in the liver release Fe3+ to be carried by transferring to ? to be combined with ?
Red bone marrow
Fe3 + Globin + B12 + Erythopoietin
What are the 4 functions of the spleen?
Filtration- spherocytes
Reservoir- 1/3 of platelets/granulocytes
Immune role- opsonizing Abs/processing Ags from encapsulated organs
Hematopoietic role
What are the three zones of the spleen and their functions?
Red pulp- RBC filter
White pulp- lymphocyte processing
Marginal zone- storage of lymphocytes and platelets
Define Spherocytes and where they’re made
Produced in spleen if RBC membranes are less deformable or if Ab coated
Spleen can produce what 3 cells if necessary?
WBCs
RBCs
Platelets
What type of lab result/finding signals PTs had a splenectomy?
Abnormal RBCs called inclusions present in peripheral circulation
What are the Granular and Agranular Leukocytes?
Granular- myleopoiesis/ granulocytopoiesis- neutrophils, eosinophils, basophils
Agranular- lymphocytes, except NK and Monocytes
How long do WBCs live for?
What is the exception?
Hrs to days
Lymphocytes live for months to years
Monocytes live for months
What WBC process is a normal response to invaders?
Which WBC process is never beneficial?
Leukocytosis
Leukopenia
Constituents and function of Neutrophil
Myeloperoxidase
Lysozyme
Defensins
Phagocytic and Microbicidal
Constituents and function of Eosinophils
Major Basic Protein
Histaminase
Helminth killing
Modulation of immediate hypersensitivity
Constituents and function of Basophils
Histamine
Immediate hypersensitivity
Constituents and function of Monocytes
Lysozyme
Phagocytic (macrophages) Ag presentation (dentrites)
Constituents and function of T-lymphocytes
Perforin
Granzye (only CD8)
Helper/suppressor (CD4)
Cytotoxic (CD8)
Constituents and function of NK Lymphocytes
Perforin
Granzyme
Cytotoxic
Which two WBCs are active phagocytes?
Neutrophils and Phagocytes, attracted by chemotaxis
What WBC responds most quickly to tissue damage?
What function do they carry out?
Neutrophils
Use lysozymes, strong oxidants and defensins to destroy bacteria
What WBC is the second to arrive to the site of tissue damage?
Monocytes are slower than neutrophils but arrive in larger numbers and destroy more microbes, enlarge and differentiate into macrophages
What WBC responsds to the sites of inflammation?
What chemicals are released?
Basophils
Heparin, histamine and serotonin to intensify inflammatory reaction
Define Emigration and what name it was formerly known by
WBCs leaving the blood stream by sticking to and squeezing between endothelial cells
Formerly known as diapedesis
What WBC are the “major” soldiers of the immune system?
Lymphocytes
What are the 3 types of lymphoctes and their functions?
B Cells- destroy bacteria and inactivate toxins, form plasma cells to produce Abs
T Cells- attack viruses, fungi, transplanted and cancer cells
NK Cells- attack infectious microbes and tumor cells
What does a Normal Plasma Cells come from?
What do plasma cells make?
Evolves from B Lymphocyte
Immunoglobulins
What is each immunoglobulin made of?
4 polypeptide chains
2 heavy chains- G A M E D
2 L chains- K L
What do myeloid stem cells develop into?
Megakaryocytes- splinter and are wrapped in plasma membrane to help stop blood loss via platelet plug formation but only live for 10 days
What are the 3 types of anticoagulants primarily used in the hematology lab?
EDTA
Heparin
Sodium Citrate
Characteristics of the EDTA tube
Lavender top
Chelating agent for Ca
Most frequent use for CBC
Excessive causes RBC shrinkage
What are the characteristics of the Green Tube
Heparin, used as an in vivo anticoagulant therapy
Binds to antithrombin 3 to catalyze the inhibition of thrombin
Define the Osmolality Fragility test?
Blood drawn in green tubes to detects whether RBCs are more likely to break down
Used to detect hereditary spherocytosis and thalassemia
What are light blue blood tubes used for?
Sodium Citrate precipitates calcium to an unstable form
Used in in coagulation studies- PT, aPTT, TT
What is measured in a CBC?
RBC count w/ morphology Hbg Hct WBC count w/ differential Platelet estimate RBC indices- MCV, MCH, MCHC, RDW (RDW technically not an RBC index)
What is one of the most common lab tests ordered?
CBC- performed by lab techs to provide info on PTs blood
What is the Rule of 3?
RBC x 3= Hgb
Hgb x 3= Hct
What causes Leukocytosis
Infections Leukemia Pregnancy Neoplasms Pneumonia Inflammation Necrosis
What causes Leukopenia
Marrow failure Radiation Chemo HIV Viral disorders
Define Total Red Blood Cell count
Count of the number of circulating red blood cells in 1mm3 of peripheral venous blood
Define Hemoglobin
Index of the oxygen carrying capacity of the blood
Define Hematocrit
% of total blood volume that is made up of RBCs