Hematopoiesis Flashcards
Hematopoiesis start to occur or begin during embryo stage in the ?
yolk sac
○ Foundation of adult hematopoietic system
○ Multipotent, specific stem cells that give rise only to any type of BLOOD CELLS
Hematopoietic stem cells (mother cell)
Characteristics of HEMATOPOIETIC STEM CELLS
Self- renewal
Directed differentiation
The nucleus and cytoplasm develop together at the
SAME RATE; Physiological—normal hematopoiesis
Synchronous hematopoiesis
Either of the nucleus or cytoplasm develops/matures later than the other; pathologic
Asynchronous hematopoiesis
decreased iron =
Decreased hemoglobin synthesis = decreased RBC production
Hemoglobin is more abundant in the -
Periphery of the RBC
Hemoglobin metabolism/synthesis is
associated with ?
erythropoiesis
protein that carry oxygen to tissues
Hemoglobin
Hemoglobin is composed of
Heme and globin
basophilic due to increased ribosome concentration for protein synthesis
Immature RBC
Patient has insufficient iron—an essential component in hemoglobin synthesis
Iron deficiency anemia
Decreased iron = delayed cytoplasm maturation
Microcytic, Hypochromic RBC
Deficiency in ? Or ? may inhibit DNA synthesis within the nucleus
Vit B12 or B9
important in DNA synthesis that occurs in the nucleus during SYNTHESIS phase of the INTERPHASE period
Vit B12 and B9
Decreased vit B12 and B9 =
delay in nuclear maturation but normal cytoplasmic maturation
essential in heme, hemoglobin, and RBC synthesis
Iron
Illness associated w deficiency in VIT 12 OR vit B9
Megaloblastic anemia
hematopoiesis that occurs in adults
Medullary hematopoiesis
primary site of hematopoiesis in adultsuntil adulthood
Bone marrow
hematopoiesis outside the bone marrow
Extramedullary hematopoiesis
Organs associated w extramedullary hematopoiesis
Kidney
Liver
Spleen
T or F
Extramedullary hematopoiesis is NOT NORMAL in adults
True
Hematopoiesis that happens within blood vessels
Intravascular hematopoiesis
Hematopoiesis that happens outside blood vessels
Extravascular hematopoiesis
TYPES OF HEMATOPOIESIS ACCORDING TO: SYNCHRONICITY
Synchronous hematopoiesis
Asynchronous hematopoiesis
TYPES OF HEMATOPOIESIS ACCORDING TO: LOCATION
Medullary/Myeloid hematopoiesis
Extramedullary hematopoiesis
Intravascular hematopoiesis
Extravascular hematopoiesis
Present in the first few hours after ovum is fertilized
Totipotent stem cells
Most versatile; can give rise to any type of cell including NERVE cell, MUSCLE cells, SKIN cells, and LIVER cells
Totipotent stem cells
- Present after several days of fertilization
- Have limited capacity to produce cell
Pluripotent stem cells
Pluripotent stem cells is derived from
Totipotent stem cell
Specific and has limited capacity to produce cell; derived from pluripotent stem cell
Multi potent stem cells
Multipotent stem cell that is limited to produce only blood cells
Hematopoietic stem cell
TYPES OF HUMAN STEM CELLS
Totipotent
Pluripotent
Multipotent
HEMATOPOIETIC DEVELOPMENTAL PERIOD
Starts in the YOLK SAC, TRANSITIONARY TYPE of hematopoiesis
Mesoblastic period
Mesoblastic period: CD marker of hematopoetic stem cells
CD34 positive cell
Mesoblastic period: HCSs are transferred to ?
CD34 positive cells
Mesoblastic period: HCs transitions into the ?
Liver
Mesoblastic period happens ? Days after fertilization up to ? Week of gestation
19 days after fertilization up to 8th-12th week of
gestation
- Initial/transient site of hematopoiesis
- Where erythroid progenitor cells are seen
Blood islands of the yolk sac
- first cell where it gives rise to cells
- Not pluripotent
- No capacity for renewal
Erythroid progenitor cells
Mesoblastic period produces ?
Primitive erythroblast
Hepatic period: Transported to the ?; temporary
liver
Medullary/Myeloid period: occurs in the ?
Bone marrow
provides nourishment to the developing embryo
Yolk sac (mesoblastic period)
where hematopoiesis takes place and site of ERYTHROID DEVELOPMENT, and the site of production of PRIMITIVE EYRTHROBLAST
Blood islands
type of hematopoiesis during mesoblastic period is ?
Intravascular
Mesoblastic period: characteristic of hematopoiesis
- extraembryonic
- transitory
- product is primitive erythroblast
Mesoblastic period
From blood island, hematopoiesis will progress in the ?
Aorta-gonad mesonephros
B cell is produced in
Spleen
Kidney
Lymphoid cell prod ccours whenand where
4th mo
Spleen
Myelopoises
When?
Produce what?
5th month
Monocytes
Lymphocytes
Megakaryocytes
Multipotent stem cell differentiates into
common lymphoid progenitor cells or a common myeloid progenitor cell
Both the myeloid and lymphoid lineages are engaged in
Dendritic cell formation
CFU-GEMM) can differentiate into
Granulocytes
Monocytes
Erythrocytes
Lymohocytes
Thrombocytes
cytokine that can trigger the growth and total number of CFU-GEMM.
Stem cell factor (SCF
States that “pluripotent stem cells now differentiate into precursor cells that are least partially dedicated to form one type of mature blood cell.”
Monophyletic theory of hematopoiesis
form directly from the common lymphoid progenitor.
Lymphoid dendritic cells
get activated in secondary lymphoid organs, it further differentiate into plasma cells.
B cells
responsible for regulating the differentiation of multipotential hematopoietic stem cells into specific cell types by the activation of transcription factors.
Cytokines
It is required for the development of all
hematopoietic lineages; in its absence
animals die during embryogenesis.
Transcription factor GATA-2:
is required for the self-renewal of HSCs, and in its absence animals die within 2 months of birth because of the failure to repopulate their red and white blood
Transcriptional regulator Bmi-1:
enhances the myeloid lineage, finally leading to the differentiation of granulocytes and macrophages
Granulocyte macrophage-colony stimulating
factor (GM-CSF
Erythropoiesis is enhanced by
decreased levels of oxygen in the blood,
hormone central to the formation of red blood cells.
Erythropoietin
Erythropoiesis takes on average ? to be completed to form mature red blood cell from unipotential hematopoietic cell.
2 days
has uncondensed nucleus and has basophilic or blue cytoplasm.
proerythroblast
nucleus becomes more condensed than the latter two stages and the cytoplasm is reduced.
polychromatophilic erythroblast stage
nucleus is much smaller than that of the prior stages having a pinker cytoplasm
orthochromatophilic erythroblast
red blood cell lacks nucleus, but still stains somewhat blue because of the remnants of polyribosomes within the cell.
reticulocyte
no nucleus and no polyribosome remnants and as a result stains pink.
mature red blood cell
white blood cells having multi-lobular nuclei and cytoplasmic granules.
Granulocytes
forms a myeloblast
unipotential hematopoietic cell
GRANULOPOIESIS
has a cytoplasm that stains blue with a large nucleus.
Myeloblast
contains azurophilic granule
promyelocyte
non-indented still rather large nucleus.
myelocyte
alike in size to a mature granulocyte and the nucleus starts to become indented.
metamyelocyte
nucleus resembles a horseshoe and has definitive indentation.
band cell
lobed mature granulocytes nucleus and cytoplasmic granules.
mature granulocytes
entire process of granulopoiesis occurs over a period of
2 weeks
committed progenitor cell, found only in the bone marrow; has a basophilic cytoplasm without granules.
monoblast
smaller in size with nuclei that become slightly indented, before becoming monocytes.
Promonocytes
kidney-shaped nuclei and can develop into dendritic cells or macrophages.
Monocytes
Lymphopoiesis first committed progenitor cells
Lymphoblasts
Lymphoblasts after maturation, differentiate into
B, T or natural killer cells.
extremely large cells within the bone marrow forms the platelet
Megakaryocytes
hepatic period
is it contains hemoglobins; no longer gowers
Third phase in hepatic period
few cells infiltrateto blood cells (precursor cells), as evident by pink cytoplasm so erythroblasts start to migrate in liver
FIRST PHASE IN HEPATIC PERIOD
Primitive rbcs have hemoglobin called
Embryonic hemoglobin
