BLOOD AND BONE MARROW

blood is considered what kind of tissue

a vascular tissue

mother cells of all tissues are

“mesenchyme”

mesenchyme differentiates into what

blood islands

blood islands differentiate into

• endothelial cells of blood vessels

• blood forming cells

the study of histology is important med and vet students bc it has

great diagnostic value

when blood is centrifuged it gives you 3 layers what are they

• top layer (plasma 55%)

• middle buffy layer (wbc & platelets 1%)

• lowest layer packed with red blood cells (hematocrit 45%)

the study of blood gives

vital information about many disorders

what disorders does the study of blood give

• leukemia

• anemia

• presence of toxins

• alcohol and variety of bacterial, viral and parasitic infections

what is the function of blood

• transport

• regulates

• prevents

• protects

what does blood transport

• o2

• co2

• nutrients, waste and hormones

blood regulates what

• body temperature

• ph

• h2o

blood prevents

fluid loss

blood protects

against toxins and infection

what are the components of blood

• plasma

• formed elements

what are the formed elements of blood

• erythrocytes (rbc)

• leukocytes (wbc)

• thrombocytes (platelets)

erythrocytes (rbc)

• are minute corpuscles and what give you that red color to blood

• no nuclei, no mitochondria, no granules

• usually biconcave

• 33% of blood is hemoglobin (Hb)

• 5.4 million in MEN & 4.8 million in WOMEN

• shape is susceptible to osmotic forces

hypotonic solution cause (rbc)

hemolysis (lysis of erythrocytes)

hypertonic solutions, fatty acids, anionic compounds and alkaline (high ph) cause?

crenation or shrinkage of erythocytes

shrinkage of erythrocytes are called?

echinocytes

hemoglobin is a …. that has how many polypeptide chains?

conjugated protein, 4 (α, β, γ, and δ)

Normal adult Hb is

• 96 % HbA (2α, 2β),

• 2 % HbA2 (2α, 2δ)

• < 2 % fetal HbF (2α, 2γ)

what condition occurs when you have abnormal hemoglobin

• sickle cell anemia

• thalassemia

“pre”-erthrocytes are called ___ & there numbers are used as___

reticulocytes, index of erythropoeisis

what are the abnormal variations in erythrocytes

• size - anisocytosis (macro or microcytosis)

• shape - poikilocytosis (spherocytosis or elliptocytosis) – spectrin defect

• hb - normo,hypo-,hyperchormic

are termed ____ bc they have no nucleus

corpuscles

erythrocytes often adhere to one another and form loose rows known as

rouleaux

erythrocytes have specific cytoskeleton components

• spectrin

• actin

• ankyrin

(MAINTAIN CELL SHAPE)

* IF DEFECTIVE CAN LEAD TO spherocytosis

erythrocytes have surface antigens called

glyoproteins

there are only 2 possible antigens

• A

• B

(THESE FORM 4 GROUPS

A,B,AB,O

there are also __ antigen forming _ & _groups

Rh antigens

Rh+

Rh-

thrombocytes (blood platelets)

• very small

• colorless

• no nucleus

• round or oval and biconcave

• 150,000-300,00/mm3

• has component of buffy coat

thrombocytes formed from fragements of _______

megakaryocytes

megakaryocytes are

very large cells with large plieomorphic nuclei

platelet zonation constists of what two?

• Granulomere (thick and central)

• Hyalomere (thin and peripheral)

granulomere

• has azurophilic granules that have active substances

  • platelet factor IV (counteracts heparin)

  • von willebrand factor (platelet adhesion)

  • platelet derived growth factor (fibroblast proliferation)

  • thromboplastin (platelet aggregation)

hyalomere

• has microtubules and actomyosin that keep the shape of the platele

von Willebrand Factor in Platelets

helps in blood clotting: when platelets activates will realse vWF forming a “plug”

platelet functions

clotting(main)

• patch defected in epithelium (small ones) by adhessions to foreign subs and aggregation to eacother

platelet plug formation

• wont adhere to endothelium (normally dont)

• when endothelium injured platelets attach to exposed connective tissue fibers

• those same platelets release ADP, and attract more platelets & forms a plug

what is coagulation or clotting

transformation of a liquid blood into a solid gel

response to tissue damage ___ and ___ events lead to the formation of ____

extrinsic, intrinsic, thromboplastin

thromboplastin and factor x help

convert prothrombin into thrombin which is an enzyme

when its thrombin it converts protein into

fibrinogen (factor I) into fibrin and leads to a clot

clotting requires

Ca++

platelet defects are

• thrombocytopenia (low platelet count)

• thrombocytopathia (abnromal shape and function)

• hemophilia (cofactor defect)

thrombocytopenia

blood fails to clot, tiny areas of bleeding can be seen under the skin

leukocytes (wbc)

• true cells

• colorless

• spherical & ameboid in tissues

leukocytes have 5 kinds in two categories

• granular leukocytes - crap ton during infection(20,00-40,00)

  • neutrophils

  • eosinophils

  • basopihils

• agranular leukocytes - lymphocytes and monocytes

neutrophils (poly)

• most abundant, 20m in circulation

• nucleus multilobed (2 or more lobes)

  • female X chromosomes have a drumstick, barr body

  • granules have no affinity to any dyes

  • get out of blood DIAPEDESIS by chemotaxis

  • capable of nonspecific phagocytosis against bacteria

  • phagocytic increases when antibodies present (opsonized particles)

neutrophils has 3 types of granules

1. specific

2. azurophilic

3. tertiary

specific granules

• lots and lack lysosomal enzymes

• contain

  • alkaline phosphatase

  • lysozymes

  • lactoferritin

  • basic antibacterial protein phagocytin

azurophilic granules

• very few and contain 3 lysosomal enzymes

  • peroxidase

  • acid phosphatase

  • b-glucuronidase

  • (MODIFIED LYSOSOMES ^)

• due to the release of lysosomal enzymes it makes neutrophiles phagocytic

tertiary granules

• has proteases

  • cathespin

  • gelatinase

neutrophils ____ to capillary endothelium at the ___ of ____

adhere

site

infection

there is adherence of neutrophils due to

• LCAM 1 (Leukocyte cel adhesion molecule 1)

• cytokines include interleukin 1 (b) and tumor necrosis factor (a)

• leukotrines from neutrophils are sythesized from arachidonic acid

eosinophils

• 1-3% same size as neutrophils

• have large cytoplasmic granules (stain pink with wright stain)

• nucleus 2-lobed with isthmus

• major basic protein (mbp) most important feature is the presence of specific granules with discoid crystal

• not normally phagocytic

eosinophills cont

• increase during allergic reactions and parasitic infections

• produce antihistamines

  • granules contain

    • lysosomal enzymes

    • MGP

    • ECP

    • EPO

    • EDN

basophils cont pt 2

• slightly smaller than eosinophiles

• hard to find in humans

• nucleus elongated

• bent

• U or s shapes

• no phagocytic activity

• coarse water soluble containing histamine and heparin

• involed in allergic reaction

basophils in blood and ___cells in tissues have common ___

mast, origin

lymphocytes

• second most abundant - intensely stained

• round and very large nuclei with thin ring of cytoplasm

• tiny gc, few mito, no er, has free ribosomes

• no specific granules

• primarily with immune response

• produce immunoglobulins in response to antigen

monocytes are

• cytoplasm abundant

• nucleus eccentric, round or kidney shaped

• 2 or more nuclei

• gc, few rer

• cytoplasmic glycogen particles

plasma includes what?

blood cells & many kinds of proteins

what are the proteins in the plasma?

• albumins

• globulins

albumins

smallest of the proteins, made in the liver

albumins function?

maintain osmotic pressure and prevent fluid loss

globulins

very large molecules that have various kinds

what are the various kinds of globulins

y-globulins or antibodies - (WORK AGAINST ANTIGENS) synthesized by lymphocytes

a and b globulins - made in liver (travel of metal ions AKA transferin)

fibrinogen

in the plasma

• made in liver

• involved in blood clotting

complement system

important in the immune system with 12+ serum proteins

plasma lipoproteins that transport lipids

VLDL - very low density lipoproteins

LDL - low density lipoproteins

HDL - high density lipoproteins

what is hemopoiesis

the formation of blood cell formation

hemopoiesis

• blood cells short lived so continuously have to be replenished

• organs that are involved are called hemoatopoietic organs

• these organs are bone marrow, spleen, and lymph nodes

bone marrow found in?

• vertebrae

• ribs

• sternum

• cranium

• pelvic

bone marrow how mucho of our body weight

4-6%

bone marrow (soft and highly cellular tissue) has precursors of what?

• blood cells

• macrophages

• adipose tissue

• reticular cells

with age what happens to bone marrow

becomes yellow and adipose tissue accumulates

in adults where is red bone marrow found

• proximal end of humerus and femur

• vertebrae

• ribs

• sternum

• ilea pelvis

prenatal hemopoiesis has 3 phases

1. mesoblastic phase

2. hepatic phase

3. myeloid phase

mesoblastic phase

during the 2nd week of gestation

• masses of mesenchymal of bulk sac and yolk sac aggregate

  • masses will differentiate into primitive erythroblasts (large, basophilic, spherical)

• form blood islands and make hemoglobin

hepatic phase

6th week of embryonic life

• round basophilic cells appear in liver

• turn into definitive erythroblasts

  • form anucleate erythroblasts

myeloid phase

4th months of gestation

• blood vessels penetrate in cavities do this through chondroblasts

mesenchymal cells move in 3 directions

osteoblast —→ osteocytes —> bone

reticular cells —> connective tissue

independent cells ——→ blood cells

hemopoiesis only occurs in adults when?

in rare disease conditions so then its called extramedullary hemopoeisis

structural organization of bone marrow

• closely packed with hemopoietic, reticular and adipose cells

• thin walled sinuses

• blood cells develop extravascularly & released into blood transcellularly

• basal lamina absent

minor supply

capillaries along sharpeys fibers

major supply

through nutrient artery

• nutrient artery enters through nutrient canal and the branches enter in Volkman’s canal

cells in bone marrow have capacity for

• self duplication

• differentiation

pluripotential hemopoietic stem cells?

if progeny can differentiate into different type of mature blood cells

unipotential hemopoietic stem cells (UPSC) or committed cells

if progeny can only differentiate into ONLY one kind of cells

erythropoiesis

1. cytoplasm changes from blue to orange, decrease in rna

2. nucleus become smaller, chromatin pattern becomes more aggregated (and eventually disappears)

3. production time is 5 days

the regulation of hemopoiesis include two factors

• hemopoietic microenvironment

• humoral (hormonal) regulation