A simple & small Presentation on hemopoietic stem cells and general formation of formed elements (Blood cells - Thrombocytes, Leukocytes, Erythrocytes) .

1. HEMOPOIETIC STEM CELLS

2. Introduction:
• Definition – Cells forming blood cells.
• Properties – 1. Self- Renewal.
2. Pluripotency.
• Types – 1. Totipotent stem cells – Give rise to all cells in a body.
2. Pluripotent stem cells – Give rise to many cells, not
all cells.

3. Pluripotent Stem Cells (PSC)
•Blood cells are derived from PSC only.
•During IUL,
At 3rd Week – Yolk Sac (Mesoderm)
At 3rd Month – Liver & Spleen
At 5th Month – Bone marrow.

4. Pluripotent Stem cells
(divides to give 2 series of cells)
Myeloid stem
cells
Lymphoid stem
cells
Multipotent Stem cells

5. Formed elements (Blood cells)
Erythrocytes
(RBC)
Leukocytes (WBC)
Granulocytes
Neutrophils
Eosinophils
Basophils
Agranulocytes
Monocytes
Lymphocytes
Thrombocytes
(Platelets)

6. Myeloid Stem Cells
Lymphoid
Stem Cells

7. Pluripotent stem cells
Multipotent stem cells
Progenitor cells/ Committed cells
(CFU-X)
Blast Cells/ Precursor cells
___________
Cell
GENERAL FORMATION OF ALL THREE CELLS

8. Myeloid Stem Cells
CFU – GEMM (granulocyte-
erythrocyte-monocyte-megakaryocyte)
Megakaryoblast
Thrombocytes
(Platelets)
Erythroblast
Erythrocytes
(RBC)
Myeloblast
Basophil Eosinophil Neutrophil Monocyte
Macrophage Dendritic cell
Mast Cell
Myeloid cells includes Red blood cells, Mast cells,
Basophil, Eosinophil, Neutrophil, Platelets,
Macrophages, Dendritic cell, monocytes.
Multipotent Stem Cell
Progenitor cell
Blast/Precursor cell

9. Lymphoid Stem Cells
CFU -
Lymphocyte
Lymphoblast
Natural
Killer cells
T -
Lymphocytes
B -
Lymphocytes
Plasma
cell
Multipotent stem cell
Progenitor cell
Blast/ Precursor cell

10. 1. Pluripotent Stem Cells
2. Multipotent Stem cells
3. Committed cells/
Progenitor Cells
4. Blast Cells/
Precursor cells
Formed elements/
Blood cells

11. Pluripotent stem cells
Multipotent stem cells
Progenitor cells/ Committed cells
(CFU-X)
Blast Cells/ Precursor cells
___________
Cell
GENERAL FORMATION OF ALL THREE CELLS

12. THROMBOCYTES (Platelets) - Formation
Pluripotent stem cell
Myeloid stem cell
Colony-Forming Units - Megakaryocyte (CFU-Meg)
Megakaryoblasts (blast cell)
Megakaryocytes
Thrombocytes (PLATELET)

13. LUEKOCYTES(WBC) - Formation
• PSC → myeloid stem cell → colony forming unit - granulocyte macrophage
(CFU-GM) → eosinophilic myeloblast (blast cell) → EOSINOPHIL
• PSC → myeloid stem cell → colony forming unit - granulocyte macrophage
(CFU-GM) → basophilic myeloblast (blast cell) → BASOPHIL
• PSC → myeloid stem cell → colony forming unit - granulocyte macrophage
(CFU-GM) → myeloblast (blast cell) → NEUTROPHIL
• PSC → myeloid stem cell → colony forming unit - granulocyte macrophage
(CFU-GM) → monoblast (blast cell) → MONOCYTE → macrophage

14. LUEKOCYTES(WBC) - Formation
• PSC → lymphoid stem cell → T lymphoblast (blast cell) → T
LYMPHOCYTE (complete development in the thymus)
• PSC → lymphoid stem cell → B lymphoblast (blast cell) → B
LYMPHOCYTE (complete development in the lymph nodes)
→ plasma cells
• PSC → lymphoid stem cell → NK lymphoblast → NATURAL
KILLER CELL

15. ERYTHROPOIESIS

16. ERYTHROCYTES (RBS) - Formation
• Erythropoiesis - The process of formation of RBCs.
• Erythropoietin (EPO) - produced by the kidney. increases RBC
precursors.
• Stages of Erythropoiesis :
PSC→ Myeloid stem cell → Colony forming unit – Erythrocyte
(CFU-E) → Proerythroblast (blast cell) → Early normoblast →
Intermediate normoblast → Late normoblast → Reticulocyte →
ERYTHOCYTE

17. CHANGES DURING ERYTHROPOIESIS
• Decrease in cell size.
• Change of cell shape (from globular to bioconcave).
• Decrease in nuclear size, later disappears.
• Cytoplasm is initially blue but later becomes red.
• Haemoglobin appears in cell cytoplasm.
• Mitosis is initially present but stops later.

18. CELL DIAMETER
(in microns)
NUCLEUS CYTOPLASM HAEMOGLOBIN MITOSIS
Proerythroblast 15 - 20 Large,
basophilic
Basophilic Absent Seen
Early
Normoblast
12 – 16 Large, nucleoli
reduce in no.
Basophilic Absent Seen
Intermediate
Normoblast
10 – 14 Nucleus
condenses
Polychromatic Appears Present
Late
Normoblast
8 – 10 Small Pyknotic Acidophilic Increases Absent
Reticulocyte 7 – 7.5 Extruded Reticular
network
Increases Absent
Erythrocyte 7 Non-nucleated Eosinophilic Abundant Absent
Changes During Erythropoiesis