1: Hematopoiesis

Hematopoiesis

\
Cell division = 2 identical daughter cells

\*1 of these cells remains as a hematopoietic stem cell → proliferate and differentiate → progenitor cells (influenced by growth facotrs, production is based on necessity) → precursor cells

* continuous, regulated process of renewal, proliferation, differentiation, and maturation of all blood cell lines
* Prenatal and postnatal hematopoiesis

RBC production

Erythropoiesis

WBC production

Leukopoiesis

granulocytic (neutrophil, basophil, eosinophil)

Myelopoiesis (under Leukopoiesis)

lymphocyte production

Lymphopoiesis

megakaryocyte

* thrombocyte / platelets

Megakaryopoiesis

1. Mesoblastic period
2. Hepatic period
3. Myeloid / Medullary period

3 stages of PRENATAL Hematopoiesis

Primitive Erythropoiesis

Mesoblastic period is AKA?

nineteenth (embryonic hemoglobin)

**Prenatal: Mesoblastic**

* begins as early as the (?) day after fertilization

erythrocytes

**Prenatal: Mesoblastic**

* only (?) are made (primitive erythroblasts)

1. Gower-1
2. Gower-2
3. Portland

**Prenatal: Mesoblastic**

* the RBCs contain unique fetal hemoglobins

1. Gower-1
2. Gower-2

**Prenatal: Mesoblastic**

* which fetal hemoglobin/s would disappear and be replaced eventually

intravascularly

**Prenatal: Mesoblastic**

* occurs (?)

yolk sac of the embryo

**Prenatal: Mesoblastic**

* location

fetal liver

**Prenatal: Hepatic**

* location

* thymus
* spleen
* lymph nodes

**Prenatal: Hepatic**

* what other organs are involved besides the liver

5-7

**Prenatal: Hepatic**

* Begins around (?) gestational weeks

extravascularly

**Prenatal: Hepatic**

* occurs (?)

Hgb F and adult hemoglobins

**Prenatal: Hepatic**

* what *substances* replaced the Gower-1 and -2 from the Mesoblastic period?

Prenatal: Hepatic

* Beginning of definitive hematopoiesis
* Megakaryopoiesis begins

4th to 5th

**Prenatal: Myeloid/Medullary**

* Begins at (?) month of fetal development

medulla of BM

**Prenatal: Myeloid/Medullary**

* location

24th

**Prenatal: Myeloid/Medullary**

* By the end of (?) weeks of gestation: BM becomes the primary site

Prenatal: Myeloid/Medullary

* Detectable levels of EPO, G-CSF, GM-CSF
* Fetal Hgb, adult Hgb

erythropoietin

**Prenatal: Myeloid/Medullary**

Meaning of EPO

granulocyte - colony stimulating factor

**Prenatal: Myeloid/Medullary**

Meaning of G-CSF

granulocyte macrophage colony-stimulating factor

**Prenatal: Myeloid/Medullary**

Meaning of GM-CSF

hypoxia

**Prenatal: Myeloid/Medullary**

stimulus of RBC production

bone marrow, RBC precursors

**Prenatal: Myeloid/Medullary**

Target EPO

delivery / birth

red marrow

childhood

at what age: all red marrow

adulthood

at what age: red marrow only in flatbones, cranium, sternum, pelvis, proximal ends of long bones

medullary hematopoiesis

Hematopoiesis in the bone marrow

extramedullary hematopoiesis

Hematopoiesis in areas other than the bone marrow

bone marrow, thymus

**Extramedullary Hematopoiesis**

2 primary lymphoid organs

spleen, lymph nodes

**Extramedullary Hematopoiesis**

2 secondary lymphoid organs

medullary hematopoiesis

* sometimes occur, even in adulthood
* damage
* diseases associated w/ hematopoiesis

1. Bone marrow
2. Liver
3. Lymph nodes
4. Spleen
5. Thymus

Name the 5 Hematopoietic tissues

inside the spongy bone

**Bone Marrow**

Located?

red; yellow

**Bone Marrow**

In a normal adult, ½ of the bone marrow is hematopoietically active (? marrow) and ½ is inactive, fatty marrow (? marrow).

* Erythroid (RBC) precursors
* Leukocyte (WBC) precursors
* Platelet precursors

**Bone Marrow**

Components (precursors)

50

**Bone Marrow**

Early in life most of the marrow is red marrow and it gradually decreases with age to the adult level of how many percent?

adipose

**Bone Marrow**

We can find the yellow marrow in the (?) cells

5-10X

**Bone Marrow**

In certain pathologic states the bone marrow can increase its activity to (?) its normal rate

hyperplastic

**Bone Marrow**

In certain pathologic states the bone marrow can increase its activity to 5-10X its normal rate. When this happens, the bone marrow is said to be?

hyperplastic

**Bone Marrow**

what do you call it when the hematopoietic stem cells exceed 70%

hyperplasia, hypercellularity

**Bone Marrow**

other terms for hyperlastic

yellow; red

**Bone Marrow**

When in hyperplastic state, the (?) marrow replaces the (?) marrow

increased or ineffective

**Bone Marrow**

Hyperplastic conditions occur where there is (?) hematopoiesis

Acute blood loss

**Bone Marrow**

a temporary replacement of the yellow marrow

Severe chronic anemia

**Bone Marrow**

erythropoiesis (RBC production) may increase to the extent that the marrow starts to erode the bone itself

Malignant disease

**Bone Marrow**

both normal red marrow and fatty marrow may be replaced by proliferating abnormal cells

Vitamin B

**Bone Marrow**

Vitamin crucial in the production of the DNA

hypoplastic

**Bone Marrow**

this can also become inactive or (?)

hypoplasia, hypocellularity

**Bone Marrow**

other terms for hypoplastic

* chemicals
* genetics
* Myeloproliferative disease that replaces hematopoietic tissue with fibrous tissue

**Bone Marrow**

becomes hypoplastic due to:

insecticides

**Bone Marrow**

example of chemical that can induce hypocellularity

CELLULARITY

**Bone Marrow**

ratio of marrow cells to fat

NORMOCELLULAR

**Bone Marrow**

30-70% HSCs

HYPERCELLULAR/HYPERPLASTIC

**Bone Marrow**

>70% HSCs

HYPOCELLULAR/HYPOPLASTIC

**Bone Marrow**

APLASTIC

**Bone Marrow**

few or no HSCs

Normal

**Bone Marrow**

Hyperplastic

**Bone Marrow**

Hypoplastic

**Bone Marrow**

Pancytopenia 

**Bone Marrow**

* deficiency of all three cellular components of the blood (red cells, white cells, and platelets)
* bone marrow doesn't produce enough healthy blood cells

M:E (myleloid:erythroid) ratio

**Bone Marrow**

ratio of granulocytes & their precursors to nucleated erythroid precursors

2:1 and 4:1 (average of 3:1)

**Bone Marrow**

Normal M:E (myleloid:erythroid) ratio

Granulocytes; erythrocytes

**Bone Marrow**

(?) are numerous because of their short survival (1-2 days) as compared to (?) of 120 days

Infection

**Bone Marrow**

6:1

neutrophils

**Bone Marrow**

(?) phagocytize bacteria and die after

neutropenia

**Bone Marrow**

low neutrophil count

neutrophilia

**Bone Marrow**

high neutrophil count

Leukemia

**Bone Marrow**

25:1

Myeloid hyperplasia

**Bone Marrow**

20:1 (high WBC count)

Myeloid hypoplasia

**Bone Marrow**

3:20 (low WBC count)

hepatocytes

**Liver**

cells in the liver

protein synthesis and degradation, coagulation factor synthesis, carbohydrate and lipid metabolism, drug and toxin clearance, iron recycling and storage, and hemoglobin degradation

**Liver**

functions of hepatocytes

hemoglobin degradation

**Liver**

function of hepatocytes in which bilirubin is conjugated and transported to the small intestine for eventual excretion

Kupffer cells

**Liver**

Contains phagocytic cells known as

Kupffer cells

**Liver**

act as a filter for damaged or aged cells in a manner similar to, but less efficient than the phagocytic cells in the spleen

splenic macrophages

**Liver**

which cell is more efficient than the Kupffer cells

bilirubin

**Liver**

degradation product of protoporphyrin

* lymph nodes
* lymphatic vessels
* drain into the left and right lymphatic duct

Composition of lymphatic system

Lymph

**Lymph Nodes**

formed from blood fluid that escapes into the connective tissue

It is because these lymph nodes are more superficial. However, lymph nodes can still be found all over the body.

**Lymph Nodes**

Why are the axillary, inguinal, and cervical lymph nodes easily found/palpated?

lymphoma

**Lymph Nodes**

cancer of lymph nodes

lymph nodes

**Lymph Nodes**

* very significant in the development of lymphocytes and macrophages
* filter the lymphatic fluid.

lymphatic fluid

**Lymph Nodes**

plasma outside the cardiovascular system

plasma

**Lymph Nodes**

the composition of lymphatic fluid is similar to (?)

3%

**Lymph Nodes**

Every time our heart beats, blood is distributed all throughout and around how many percent of our plasma leaks out and enters the connective tissues?

lymphocytes, macrophages, and a reticular network

**Lymph Nodes**

composition

medulla

**Lymph Node**

Structure

* inner area
* plasma cells

plasma cells

**Lymph Nodes**

Structure

* these cells are derived from B lymphocytes
* involved in antibody producion

cortex

Lymph Node

Structure

* outer area
* follicles, B lymphocytes

B lymphocytes

**Lymph Nodes**

Structure

* these cells are involved in humoral immunity

plasma cells, memory cells

**Lymph Nodes**

Stucture

* B lymphocytes can develop into what 2 types of cells?

memory cells

**Lymph Nodes**

Structure

* cells for recognition

paracortex

Lymph Node

Structure

* T lymphocytes
* macrophages