HEMATOPOIESIS & STEM CELL THEORY PPT

Question 1

Capable of self renewal and directed differentiation into required cell lineages.

Answer 1

Hematopoietic Stem Cell (HSC)

Question 2

This is the continuous, regulated process of renewal, proliferation, differentiation,
and maturation of all blood cell lines which result in the formation, development, and specialization of all the functional blood cells.

Answer 2

HEMATOPOIESIS

Question 3

HEMATOPOIESIS IN: select distribution of embryonic cells in specific sites that rapidly changes during development

Answer 3

Developing human

Question 4

HEMATOPOIESIS IN:
restricted primarily to the bone marrow

Answer 4

ADULT

Question 5

3 PHASES OF HEMATOPOIESIS:

Answer 5

-MESOBLASTIC PHASE
-HEPATIC PHASE
-MYELOID/ MEDULLARY PHASE

Question 6

Begins around the 19TH day of embryonic development after fertilization.

Answer 6

MESOBLASTIC PHASE

Question 7

Formation of a primitive vascular system.

Answer 7

MESOBLASTIC PHASE

Question 8

First hematopoietic cells (erythroblasts) are generated in the?

Answer 8

yolk sac

Question 9

In MESOBLASTIC PHASE, what are the embryonic hemoglobins?

Answer 9

Gower I- 2 epsilon, 2 zeta chains
Gower II- 2 alpha. 2 epsilon chains
Portland- 2 zeta, 2 gamma chains

Question 10

Hepatic Phase begins at what gestational weeks?

Answer 10

5 to 7 gestational weeks.

Question 11

Becomes the major site of
hematopoiesis during the 2nd trimester of
fetal life and reaches its PEAK by the 3rd
month of fetal development.

Answer 11

HEPATIC PHASE: Liver

Question 12

What are the developing clusters found in during HEPATIC PHASE ?

Answer 12

red blood cell
granulocytes,
monocytes
megakaryocytes

Question 13

Predominant in Hemoglobin production

Answer 13

Fetal Hemoglobin ( Hemoglobin F)

Question 14

In HEPATIC PHASE: ADULTS PREDOMINANT HEMOGLOBIN:

Answer 14

Hb A1: 95% (2 alpha, 2 beta)
Hb A2: 2-3% (2 alpha, 2 delta)
Hb F: 1-2 % (2 alpha, 2 gamma)

Question 15

In hepatic phase the first fully developed organ in the fetus, becomes the major site of T cell production.

Answer 15

Thymus

Question 16

produce B cells in the Hepatic Phase

Answer 16

liver & Spleen

Question 17

Occurs in the medulla or inner part of the bone cavity) & begins between , what month of fetal development?

Answer 17

fourth and fifth month: MEDULLARY (MYELOID) PHASE

Question 18

__________is apparent during medullary phase/myeloid phase.

Answer 18

Myeloid activity

Question 19

the myeloid-to-erythroid ratio gradually approaches to?

Answer 19

3:1 to 4:1 (normal adult levels).

Question 20

By the end of ________weeks’ gestation, the bone marrow becomes the primary site of hematopoiesis.

Answer 20

end of 24 weeks

Question 21

Adult hematopoiesis happens in what organ?

Answer 21

Bone marrow

Question 22

What are the three embryonic hemoglobins ?

Answer 22

Gower I- 2 epsilon, 2 zeta chains
Gower II- 2 alpha. 2 epsilon chains
Portland- 2 zeta, 2 gamma chains

Question 23

What are the sites of hematopoiesis for the following phases of embryonic hematopoiesis?

Mesoblastic phase
Hepatic phase
Medullary phase

Answer 23

Mesoblastic phase- yolk sac
Hepatic phase- liver
Medullary phase- bone marrow

Question 24

2 theories describing the origin of hematopoietic progenitor cells.

Answer 24

MONOPHYLETIC THEORY
POLYPHYLETIC THEORY

Question 24

Capable of self renewal and directed differentiation into required cell lineages.

Answer 24

Hematopoietic Stem Cell (HSC)

Question 25

MONOPHYLETIC THEORY Suggests that all blood cells are derived from a single progenitor stem cell called a

Answer 25

pluripotent hematopoietic stem cell.

Question 26

The most widely accepted theory among experimental hematologists.

Answer 26

MONOPHYLETIC THEORY

Question 27

Capable of self-renewal, are pluripotent and give rise to differentiated progeny.

Answer 27

Hematopoietic Stem Cells (HSCs)

Question 28

Hematopoietic Stem Cells (HSCs) can differentiate into progenitor cells committed to either

Answer 28

lymphoid or myeloid lineage.

Question 29

Where all lymphocytes are derived (B & T lymphocytes)?

Answer 29

Lymphoid progenitor cell

Question 30

Natural killer lymphocyte and dendritic lineages.

Answer 30

Lymphoid progenitor cell

Question 31

This cell line progresses to the progenitor colony- forming unit granulocyte- erythrocyte - monocyte- megakaryocyte (CFU- GEMM).

Answer 31

Myeloid progenitor cell

Question 31

Capable of self renewal and directed differentiation into required cell lineages.

Answer 31

Hematopoietic Stem Cell (HSC)

Question 32

General characteristics of cell maturation:

Answer 32

* Decreased cell diameter * Decreased nuclear diameter * Loss of nucleoli * Condensation of nuclear chromatin * Decreased basophilia in cytoplasm * Loss of the nucleus (unique to RBCs only)

Question 33

Hematopoietic Stem Cells (HSCs) is directed to one of three possible fates:

Answer 33

self-renewal differentiation apoptosis.

Question 34

POLYPHYLETIC THEORY Suggests that each of the blood cell lineages is derived from its__________

Answer 34

own unique stem cell.

Question 35

Considered only site of definitive hematopoiesis during embryonic development.

Answer 35

AGM (aorta-gonad-mesonephros) REGION

Question 36

Major site of adult formation on the embryo

Answer 36

Yolk sac

Question 37

Seperated from human umbical cord blood coud generate hematopoietic as well as endothelial cells on vitro

Answer 37

Flk1-HSCs

Question 38

Mixture of heme and globin

Answer 38

Hemoglobin