Mcp Lect 36: Hematology

Front 1

General characteristics of blood

Back 1

General Features of Blood

1. Type of connective tissue
2. Transport
-oxygen and other nutrients
-waste products
-hormones
-heat
-cells
3.Clinical tests
-Hematocrit
-Differential count

Front 2

Formed elements of blood

Back 2

Cellular elements

1. Erythrocytes red blood cells (RBC)


2. Leukocytes white blood cells (WBC)
a. Granulocytes - neutrophils, eosinophils, basophils
b. Agranulocytes - monocytes, lymphocytes

a) Granulocytes contain specific granules in their cytoplasm; have segmented nuclei
1) Neutrophils contain neutrophilic staining granules
2) Eosinophils contain eosinophilic staining granules
3) Basophils contain basophilic staining granules

b) Agranulocytes ("mononuclear cells") lack specific granules (but do contain non specific granules); nuclei tend to be spherical or slightly indented
1) Monocytes immature form of macrophage
2) Lymphocytes central cell of immune response


3. Platelets small packets of cytoplasm which lack nuclei

Front 3

Composition of Plasma

add image - plasma proteins

Back 3

II. COMPOSITION OF PLASMA
1. WATER (90%)

2. SOLUTES (10%)
A. Plasma proteins
-albumin (50-60%), immunoglobulins (gamd), globulins (a/b/g), fibrinogen (7%), complement, lipoprotein
B.. Organic solutes
-glucose, amino acids, organic acids, vitamins, hormones
C.. Inorganic solutes
- electrolytes Na+, K+, Cl ; blood gases; others

**note that the platelets are in between the buffy coat and plasma.
RBC at bottom, plasma has proteins, buffy coat is WBC

Front 4

How do you measure hematocrit?

Back 4

hematocrit = packed cell volumetake blood in small centrifuge tube, centrifuge get packed cells40-50% under normal conditions is cellular componentvaries among individuals gender age

=RBC/TBV

Front 5

How do you measure differential count?

Back 5

DIFFERENTIAL COUNT is the number of each type of leukocyte in the blood

- expressed either as an absolute # / unit volume or as a relative % of total WBC count
– the cellular elements are demonstrated by preparing a blood smear and treating it with an alcohol solution of a Romanovsky-type stain which simultaneously fixes and stains the cells
- Romanovsky-type stains (e.g. Wright's, Giemsa) yield four basic staining patterns:
a) basophilic (blue),
b) azurophilic (purple),
c) eosinophilic (orange) and
d) neutrophilic (salmon pink)

do differential count OLD way; drop of blood on slide back up another slide to drop push forward get a feathered edge (D) get gradation in thickness of the smear where you can see cells not on top of each other and you can do a cell count .. This is somewhere in middle to get an adequate countnow done w machine

Front 6

Romanovsky-type stains

Back 6

- Romanovsky-type stains (e.g. Wright's, Giemsa) yield four basic staining patterns:
a) basophilic (blue),
b) azurophilic (purple),
c) eosinophilic (orange) and
d) neutrophilic (salmon pink)

do differential count OLD way; drop of blood on slide back up another slide to drop push forward get a feathered edge (D) get gradation in thickness of the smear where you can see cells not on top of each other and you can do a cell count .. This is somewhere in middle to get an adequate countnow done w machine

Front 7

Diapedesis

Back 7

Diapedesis - All leukocytes exhibit amoeboid movement and have the ability to migrate through the endothelium (especially capillaries and venules) to enter the extravascular tissues. This process is greatly increased in areas of inflammation (e.g. due to cytokines). Erythrocytes and platelets are normally confined within blood vessels

Front 8

Granulocytes

Back 8

1. Eosinophils
2. Neutrophils
3. Basophils

Front 9

Agranulocytes

Back 9

1. Lymphocyte
2. Monocyte

Front 10

Serum

Back 10

PLASMA - FIBRINOGEN = SERUM

Front 11

Structure of erythrocyte membrane

Back 11

A submembrane "skeleton" maintains the biconcave disc shape and stabilizes the cell against shearing forces - contains spectrin, actin and other proteins; this submembrane lattice is attached to the membrane by ankyrin

*note BAND3 = aniohn transporter channel

b. RBC membrane contains numerous glycolipids, transmembrane glycoproteins (e.g. glycophorin), and anion transport channels (band 3); the carbohydrate portion of these molecules is responsible for ABO blood types and helps prevent agglutination (negative charge)

Front 12

Sugars composing ABO blood types

Back 12

O Antigen: -Lipid-Glucose-Galactose-N-Acetylglucosamine-Galactose-Fucose

A Antigen: N-Acetylgalactosamine (GalNac) glycosidically bonded to O antigen

B Antigen: Galactose glycosidically bonded to the O antigen

Front 13

Anemia

definition and causes

Back 13

Anemia – low concentration of hemoglobin in the circulatory system

Causes
1. Loss of blood – hemorrhage
-Or trauma

2. Insufficient production of RBCs (e.g. low erythropoietin (epo) from diseased kidney)
-Common in people who have kidney disease
-Add epo to dialysis fluids bc kidneys make epo, no longer making epo .. Need epo to stimulare RBC production in bone marrow

3.RBCs with insufficient hemoglobin e.g. iron deficiency
-Common almost universally in pregnant women
-Pregnant women can be given iron supplement

4. Accelerated RBC destruction e.g. sickle cells

Front 14

RBC life cycle

Back 14

Lifecycle of RBCtakes a week to produce, released as reticulocyte, circulate for 120 days, no nucleus no fixing proteins etc, rbc becomes inflexible removed by spleenmost removal takes place outside of vasculature by spleen but also liver and BM<10% us removed intravascularly via phagocytosis

Destruction aged or damaged RBC become less flexible and are removed primarily by the spleen (phagocytosed by macrophages) and also by the liver and bone marrow - macrophages catabolize hemoglobin into Fe and bilirubin.

Front 15

Polycythemia

Back 15

a disease state in which the proportion of blood volume that is occupied by red blood cells increases. Blood volume proportions can be measured as hematocrit level.

It can be due to an increase in the number of red blood cells[1] ("absolute polycythemia") or to a decrease in the volume of plasma ("relative polycythemia")

Front 16

The integrity of an erythrocyte during its lifespan depends upon

Back 16

The integrity of an erythrocyte during its lifespan depends upon the cell membrane, hemoglobin, and metabolic enzymes.

Front 17

Hemoglobin structure and types

Back 17

Hb is an iron containing respiratory pigment:
a. Heme (each Hb molecule has four heme groups) -iron (oxygen binding site) - porphyrin ring
b. Globin
- a tetramer consisting of two pairs of globin chains
- differences in the globin moiety are responsible for the differences between embryonal, fetal (HbF), and adult (HbA, HbA2) hemoglobins
- in normal adults, HbA comprises 97% of the total Hb,
- HbA2 forms 2-3%
- HbF forms less than 1%.

Front 18

Normochromic

Back 18

Normochromic normal Hb concentration

Front 19

Polymorphonuclear lymphocytes

Back 19

Neutrophils

Front 20

RBC life span?

Back 20

120 days

Front 21

RBC energy source?

Back 21

most glucose metabolism via anaerobic glycolysis; provides ATP for maintaining membrane integrity and Hb function

Front 22

Talk about erythrocyte organelles

Back 22

Erythrocytes lack most subcellular structures (i.e., nucleus, ribosomes, mitochondria) and lack a capacity for protein synthesis (including hemoglobin!)

Front 23

Band cell

Back 23

young neutrophil whose nucleus has not completed its segmentation

Front 24

How do neutrophils kill?

Back 24

microbe killing
mostly bacteria or fungi
better killing via opsonization

1) oxygen dependent mechanisms
(oxidative/respiratory burst)
- generates oxygen radicals which can kill infectious agents
-Superoxide radicals (O2-),
Hydrogen peroxide (H2O2) also converted by MPO into hypochlorous acid (HOCl)

2) oxygen independent mechanisms
- proton pump acidifies contents of phagosome and granule fusion - specific + azurophilic granules dump contents

Front 25

A. Structure
B. Function
C. Numbers and distribution

Back 25

A. Structure
1. Nucleus
a. Nucleus consists of 2 5 lobes (a cell with more than 5 lobes is called hyper-segmented)
b. About 3% of neutrophils in women may have a drumstick appendage attached to the nucleus; this represents the inactivated X. May not see the barr body if it is hidden behind the nucleus in the smear you're looking at.
chromosome
c. Band cell -- young neutrophil whose nucleus has not completed its segmentation


2. Cytoplasm
a. Specific granules
- stain salmon pink (neutral)
- majority of the granules smaller than azurophilic granules and cannot be resolved with the light microscope
- contain lactoferrin, NADPH oxidase, lysozyme, vitamin B12 - binding protein, alkaline phospatase
- On EM appear smaller and pale (are peroxidise negative)
b. Azurophilic (non specific) granules
- stain reddish purple
- present in all leukocytes but most clearly seen in neutrophils in which they make up 10 - 20% of the granules
- contain myeloperoxidase, defensins, bacterial permeability increasing protein, acid hydrolases, and proteolytic enzymes
- on EM, they large and dense (are peroxidase +)


B. Function - INGESTION AND DESTRUCTION of extracellular bacteria and fungi, acute inflammation, movement to site of infection via chemotaxis and diapedesis, can be oxygen dependent (respiratory burst) or independent killing mechanisms

1. Neutrophils are motile phagocytic cells whose primary function is the ingestion and destruction of invading microorganisms(especially
extracellular bacteria and fungi) these cells play a central role in acute inflammation

2. Movement to the site of infection [Fig 11 13] is initially mediated by complementary adhesion molecules on the surface of both
neutrophils & endothelial cell:
a. margination (rolling/sticking) – selectins, integrins (adhesion molecules)
b. diapedesis and chemotaxis - the recruitment of neutrophils (and other WBC) is controlled by chemokines (chemotactic cytokines)
which are secreted by resident tissue cells in areas of inflammation – results in increased expression of surface adhesion molecules,
and increased recruitment/margination of leukocytes
6 hours doing diapedesis, take 1-4 days to move through tissue to area of damage, then form PUS

3. Interaction with microorganisms [Fig 14]
a. recognition - via receptors
b. phagocytosis results in phagosome formation; greatly enhanced if the bacteria are coated with antibodies or complement
(opsonization)
c. microbe killing
1) oxygen dependent mechanisms
(oxidative/respiratory burst)
- generates oxygen radicals which can kill infectious agents
2) oxygen independent mechanisms
- proton pump acidifies contents of phagosome and granule fusion - specific + azurophilic granules dump contents
d. Contains few mitochondria but abundant glycogen so neutrophils can function under anaerobic conditions

4. Cell membrane - contains various receptors which facilitate emigration to sites of inflammation and the identification of targets (e.g. bacteria or fungi)



C. Numbers and Distribution [Fig 15]
1. Most common leukocyte in blood (60-70% of WBC):
a. circulating pool (50%) - moving as suspended in blood
b. marginated pool (50%) - reversibly stuck to endothelium of tissues (esp lung)
2. Intravascular lifespan = 6 hours
3. Tissue lifespan = 1 4 days - most die in perivascular tissues
4 There is a large reserve pool of neutrophils in the bone marrow (10 X the number in blood!)
-the total blood neutrophil pool is distributed between the marginal neutrophil pool and the and the circulating neutrophil pool. When blood samples are drawn for the leukocyte and differential counts, the specimins only reflect the status of the circulating neutrophil pool.

Front 26

A. Structure
B. Function
C, Numbers and Distribution

Back 26

EOSINOPHIL

A. Normal Structure
1. Nucleus the eosinophil usually has a bilobed nucleus

2. Cytoplasm - specific and nonspecific granules
a. Specific granules prominent eosinophilic granules which are large and spherical:
1) Externum less dense matrix; contains PEROXIDASE and HYDROLYTIC LYSOSOMAL ENZYMES
2) Internum rectangular central crystalline core (crystalloid) which consists primarily of major BASIC protein which has anti-parasitic properties and provides eosinophilic character to the granule (most abundant granule protein); also eosinophil cationic protein (most potent tissue damaging protein in eosinophils) - also eosinophil-derived neurotoxin
b. Azurophilic (non specific) granules


B. Function - kill parasites, anti-inflammatory effects .. can also produce neurotoxin, remember it attacking schistozoma .. can also undergo chemotaxis
1. Distinctive function of attacking and killing parasites which invade tissues

2. Anti inflammatory effects - "damage control of allergic reactions"
a. phagocytosis of antigen antibody complexes
b. release enzymes which hydrolyze/neutralize chemical mediators involved with allergic reactions (e.g. those produced by mast cells and basophils)
-Also limits inflammation by inactivating leukotrienes and histamine



C. Numbers and Distribution
1. Preferentially reside in tissues with an epithelial interface with the environment (respiratory/gastrointestinal/ lower genitourinary tracts)
2. Are attracted to sites of allergic inflammation by eosinophil chemotactic factors (ECF) which are released by mast cells and basophils

Front 27

A. Structure
B. Function
C. Numbers and Distribution

Back 27

BASOPHIL

-basophils are granulocytes which are similar, but not identical, to mast cells - mast cells have round or oval nuclei

A. Structure **SPECIAL RECEPTORS FOR IGE ON SURFACE
1. Nucleus - -usually has 2 3 lobes - often less segmented than in neutrophils
2. Cytoplasm
a. specific granules intense basophilic granules which may obscure the nucleus (fewer but larger than granules in mast cells)
b. azurophilic (non specific) granules
3. Membrane Receptors basophils (and mast cells) have special receptors which hold IgE (a type of antibody) on their cell surfaces - when IgE reacts with an antigen, this activates the cell to release various chemical mediators which have potent inflammatory effects:
4. Preformed Mediators (stored in specific granules)
a. histamine – causes the contraction of smooth muscle in the lungs (and causes relaxation of smooth muscle in other locations)
b. proteases
c. heparin (responsible for granule basophilia)
d. eosinophil chemotactic factor (ECF)
5. De Novo Synthesis of Mediators -- whereas preformed mediators are stored in the specific granules, other mediators (e.g. leukotrienes) are not formed until the cell has been activated.

B. Function -- hypersensitivity, defense against parasites (attract eosinophils which then kill parasites)
1. Basophils are motile phagocytic cells that may play an important role in host defense against parasites by releasing factors which are chemotactic for eosinophils (which then kill the parasites)
2. Basophils (and mast cells) play an important role in certain immune mediated diseases, especially immediate hypersensitivity
-IgE on surface of basophileforeign antigen enters body, antigen crosslinkes to adjacent ige molecules, initiates signal transduction cascade, get Ca2+ moving, fusion of cytoplasmic granules, liberates heparin, leukotiens, etc to surrounding connective tissue to initiate inflammatory response
-ALSO IMPORTANT IN ASTHMA



C. Numbers and Distribution least common leukocyte

Front 28

What cell mediates the response that leads to asthma?

Back 28

Basophils
(and mast cells)

Front 29

A. Structure
B. Function
C. Numbers and Distribution

Back 29

A. Normal Structure
1. Size In the normal individual, most of the circulating lymphocytes are small (8 9 um); however a few may be medium to large (16 um) which represent activated lymphocytes responding to an antigen
2. Nucleus usually round and heterochromatic
3. Cytoplasm
a. smaller lymphocytes have only a thin rim of basophilic cytoplasm
b. may contain a few azurophilic granules

B. Function lymphocytes are the central cells of the immune system -- B and T cells

C. Numbers and Distribution
1. second most numerous leukocyte (28% -- first most numerous is neutrophil)
2. unlike other leukocytes, lymphocytes can:
a. reenter the blood via lymphatics (i.e. recirculate)
b. retain ability to divide (in response to antigens)
c. certain lymphocytes can survive for many years

Front 30

A. Normal Structure
B. Function
C. Numbers and Distribution

Back 30

MONOCYTES --> MACROPHAGES

A. Normal Structure
1. Size the largest leukocyte
2. Nucleus a variety of shapes; eccentric; typically has indentation (e.g. horseshoe shape) but is not segmented or lobed; may have 2 3 nucleoli
3. Cytoplasm
a. typically grey-blue with a few azurophilic granules and vacuoles
b. relatively more cytoplasm compared to lymphocytes

B. Function - Phagocytosis, Secretion, APC
***Monocytes are the circulating precursors of tissue macrophages and other specialized phagocytic cells which form the mononuclear phagocyte system (MPS)

Main functions:
a. Phagocytosis
-principally against intracellular bacteria, viruses, fungi, and protozoa; also remove tissue debris
b. Secretion
-macrophages release several cytokines involved with host defense and inflammation (e.g. interleukin 1 and tumor necrosis factor)
c. Antigen processing/presentation
- interaction with lymphocytes in the mediation of the immune response
"
C. Numbers and Distribution
1. circulating lifespan = 40 hours
2. tissue lifespan is thought to be months
3. random migration of monocytes into different tissues (in the absence of inflammation)
4. once in the tissues, monocytes probably do not reenter the circulation

Macrophages:
LIVER – Kupffer cells
LUNG – Interstitial and Alveolar macrophages
SEROUS CAVITIES – Pleural and Peritoneal macrophages
BONE -- Osteoclasts
BRAIN – Reactive Microglial Cells
GRANULOMA - Multinucleated Giant Cell

Front 31

A. Normal Structure
B. Function
C. Numbers and Distribution

Back 31

Platelets

A. Normal Structure [Fig 16]

1. Size and Shape - about 2-3um in diameter - ovoid or disk shaped,

2. Cytoplasm
a. No nucleus but does have most other organelles (e.g. mitochondria)
b. Has two areas with distinct staining properties:
1) Hyalomere outer light bluish staining area containing actin myosin and marginal bundle of microtubules which help maintain its ovoid shape actin is the most abundant protein
2) Granulomere inner (central) purple area -- secretory storage granules form about 20% of the volume of a platelet by electron microscopy, three types of granules are observed:
a) Dense granules -- contain serotonin, ADP, calcium
b) Alpha granules -- modified lysosomes; contain substances related to blood clotting (e.g. PF4, vWF) and vessel repair (platelet derived growth factor PDGF)
c) Lamda -- Granules (lysosomes) – acid hydrolases
c. Canalicular membrane system -- open channels which are thought to facilitate release of granule contents
d. Dense tubular system – throughout cytoplasm - prostaglandin synthesis?

3. Platelet membrane - contains membrane glycoproteins (GP; integrins) which serve as receptors for adhesive proteins (vWF and fibrinogen) which are critical for platelet adhesion and aggregation

4. Activation
a. Platelet activation is accompanied by the dramatic morphologic change from the disk shape to a sphere with extended pseudopods.
b. Mediator release in the process of hemostasis, platelets secrete their granule contents and initiate prostaglandin synthesis (thromboxane) from arachidonic acid



B. Function - play an important role in hemostasis and vascular repair



C. Numbers and Distribution
1. in circulation they exist individually; in blood smears they frequently clump
2. up to 33% of all blood platelets are stored in the spleen (red pulp)
3. circulating lifespan = 10 days.

Front 32

Hemostasis

Back 32

A. General Information
-hemostasis is a complex series of physiologic and biochemical events involving both promoters and inhibitors of blood coagulation.
-The hemostatic process is designed to maintain blood in a fluid state yet confined within the blood vessels.

B. Key Steps in Clot Formation
1. Reflex vasoconstriction
2. Platelet adhesion
-within seconds, platelets adhere to subendothelial collagen
- this is mediated via vonWillebrand's factor (vWF)
***If you have break in blood vessel and expose underlying collagen platelets stick IMMEDIATELY to SUBENDOTHELIAL COLLAGEN **
3. Contact activation and release
-as platelets stick to subendothelial collagen, they begin to release mediators which enhance hemostasis
4. Platelet aggregation
- platelets begin to stick to each other (via fibrinogen) quickly forming a primary platelet plug (primary hemostasis)
5. Fibrin formation
- although a primary platelet plug quickly blocks bleeding, it is neither very strong nor lastingly effective. As a result of clotting factors ("coagulation cascade"), the enzyme thrombin is formed which initiates conversion of soluble fibrinogen into insoluble fibrin which, over a period of hours, provides a more definitive hemostatic plug (secondary hemostasis)
6. Clot retraction
-condensation of clot which involves platelet cytoskeleton (actin, myosin) and ATP

Front 33

Is production of ROS by (name that cell) always a good thing?

Back 33

Neutrophils make ROS in oxygen dependent killing mechanism

bc neutrophils make ROS, they can inadvertently damage DNA and cause cancerhere talking about oxidative damage to cells.. Hear a lot about antioxidantsantioxidants counteract production of ROShave large production of ROS as a consequence of infection that body is trying to neutralize, in addition to neutrophils knocking off bacteria they can damage normal cells adjacent to infection, can damage DNA, maybe cause a mutation, over lifespan of multiple damage to cells by ROS can have enough mutations that they cause cancer. NSAIDs like ibuprofen, aspirin, celebrex, lots of good epidemiological data that they can have an anticancer effect  colon cancerpeople w familial predisposition to colon cancer take NSAID dailyalso prostate, maybe other types of cancer. No hard and fast rule.Other side effects of NSAIDs like intestinal bleedingelderly people who take NSAIDs to protect against arthritis as daily routine.. By taking NSAIDs for that also helps protect against cancers caused by inflammation.

Front 34

break down the WBC composition of the blood

Back 34

Neutrophil 60-70%

Eosinophil 2-4%

Basophil 0.5%

Lymphocyte 28%

Monocyte 5%

Front 35

Macrophages in the
LIVER
LUNG
SEROUS CAVITIES
BONE
BRAIN
GRANULOMA
are called?

Back 35

LIVER – Kupffer cells
LUNG – Interstitial and Alveolar macrophages
SEROUS CAVITIES – Pleural and Peritoneal macrophages
BONE -- Osteoclasts
BRAIN – Reactive Microglial Cells
GRANULOMA - Multinucleated Giant Cell

Front 36

What is Hemophilia A caused by?

Back 36

Hemophilia A is absence of Factor VIII (Von Willebrand's Factor).