Chapter 7- Hematopoiesis Flashcards
- A term used to signify production of blood cell
- process of blood cell production that includes cell renewal, proliferation, differentiation, and maturation.
Hematopoiesis
Where is the result of the process of hematopoiesis released?
from the bone marrow to the circulation
life span of RBC
120 days
A hematopoietic stem cell is capable of self-renewal and directed differentiation into all required cell lineage.
TRUE
In healthy adults hematopoietic is restricted primarily to the
Bone marrow
Mesoblastic phase
previously been considered to be the only site of definitive hematopoiesis during embryonic development.
Hepatic phase
who concluded that the yolk sac was the major site of adult blood formation in the embryo
Metcalf and Moore supported by Weissman and colleagues.
The precise origin of the adult HSC remain UNSOLVED
TRUE
Hepatic Phase
- begins at 5 to 7 gestational weeks
- characterized by recognizable clusters of developing erythroblast, granulocytes, and monocytes colonizing the fetal liver, thymus, spleen, placenta, and ultimately the bone marrow space in the final medullary phase
Hematopoiesis in the aorta-gonad mesonephros region and the yolk sac disappear during this stage
hepatic Stage
the first fully developed organ in the fetus, becomes the major site of T cell production.
thymus
major site of production of B cell
Kidney and spleen
In what phase does production of megakartocytes begin?
hepatic phase
In what phase does fetal hemoglobin (Hb F) is the predominant hemoglobin, but detectable lvels of adult hemoglobin (Hb A) may be present.
Hepatic phase
prior to the fifth month development, hematopoiesis begins in the bone marrow cavity, this transition is called
Medullary (Myeloid phase
Where does Medullary hematopoiesis occur?
Medulla or inner part of the bone
What phase does HSCs and mesenchymal cells migrate into the core of the bone.
medullary phase
By the end of 24 weeks of gestation, what is now the primary site of hematopoiesis?
Bone marrow
Hematopoietic activity, especially myeloid activity is apparent during this stage of development, and the myeloid-to-erythroid ratio gradually approaches 3:1 (adult level)
Myeloid Phase
Erythropoietin (EPO), granulocytes colony-stimulating factor (G-CSF), granulocyte-macrophage colony stimulating factor (GM-CSF), and hemoglobin F and A can be detected
Myeloid Phase
cells at various stages of maturation can be seen in all blood cell lineage
myeloid phase
Adult hematopoietic tissue is located in
Bone marrow, lymph nodes , spleen, liver and thymus
two major components of bone marrow
- red marrow
- yellow marrow
haematopoietically ACTIVE marrow consisting of the developing blood cells and their progenitors
Red Marrow
haematopoietically INACTIVE marrow composed primarily of adipocytes (fat cells), with undifferentiated mesenchymal cells and macrophages.
Yellow marrow
process of replacing the active marrow by adipocytes during development is called
retrogression
The major site of blood cell production during the second trimester of fetal development
Liver
Monophyletic theory
Suggest that all blood cells arise from a single stem cell called PLURIPOTENT HEMATOPOEITIC STEM CELL
it suggest that each of the blood cell lineages is derived form its own unique stem cell
Polyphyletic theory
-the most versatile type of stem cell, can develop into any human cell type, including development from embryo to fetus
-present in first few hours after an ovum is fertilized
Totipotential stem cell
-these are present several days after fertilization
-they cannot develop into a fetus
Pluripotential stem cell
-it is derived from pluripotent stem cell
-limited to specific types of cell to form tissues
Multipotential stem cell
it provides protective and nourishing environment to the HSCs
Stromal cells
Examples of Stromal Cells
Fibroblast
Osteoclast and osteoblast
Reticular adventitial cell
Macrophage/monocyte
Adipocyte
Lymphocyte
Endothelial cell
Glial cell
Perivascular
it begins around 19th day of embryonic development after fertilization
-stage for primitive erythroblast
Mesoblastic or yolk sac phase
Embryonic hemoglobin
Gower I
Gower II
Portland
The hepatic phase of hematopoiesis begin at 5th to 7th week of gestation
-stage for the beginning of definitive hematopoiesis with a decline primitive hematopoiesis in the yolk sac
Hepatic phase
it is the predominant hemoglobin during the hepatic phase
Hemoglobin F
in adult hematopoiesis, the red marrow is found only in
Ribs
Sternum
Vertebrae
Pelvic, proximal end of long bones
It is the process of replacing the active marrow by adipocyte (yellow marrow)
Retrogression
normal myeloid to erythroid ratio
2:1, 3:1, 4:1
ratio of marrow cells to fat
marrow cellularity
Site of adult hematopoietic tissue
Bone marrow (major site)
Liver
thymus
Spleen
Lymph nodes
most commonly used site for bone marrow collection
Posterior iliac crest
is it very rarely used site
-for lie supine position
Anterior iliac crest
needle used for trephine core biopsy
trephine biopsy needle
jamshidi needle
westerman-jensen needle
needle used for bone marrow aspirate
aspiration needle
university of illinois sternal needle
Bone marrow smears should be retained for
10 years
how many cells should be counted for a bone marrow differential
atleast 500, and preferably 1000 cells
The most predominant cell in the bone marrow
metamylocyte
