Blood and lymph Hematopoiesis 1 Blood components and
Blood and lymph Hematopoiesis 1. Blood components and functions 2. Plasma 3. Erythrocytes 4. Leucocytes 5. Theories of hematopoiesis 6. Stem cell structure and functions 7. Embryonic and postembryonic hematopoiesis 8. Classes of hematopoietic cells 9. Main features of different hematopoietic lines
Tissues of inner environment 1. Blood and lymph 2. Connective tissues Blood functions Transport 1. Trophic 2. Respiration 3. Humoral 4. Excretion Protective Homeostatic
Blood= cells + plasma (RBC+WBC+PL) hematocrit VFe/Vpl
Plasma physical condition – colloid solution chemical composition: 90 -93 % water 7 -10 % dry residue (7% proteins; albumins 4%, globulins 1 -3%, fibrinogen 0, 2 -0, 4%) others 3% (enzymes, vitamins, salts, waste products…) p. H 7, 36
Hemogram (general blood analysis) Hematocrit 45: 55 Erythrocytes men women 3, 9 -5, 5 x 10 12/l 3, 7 -4, 9 x 10 12/l Reticulocytes 2 -10 per 1000 erythrocytes Hemoglobin men 130 -160 g/l women 120 -140 g/l Leucocytes 4 -9 x 10 9/l Platelets 180 -320 x 10 9/l Speed of blood sedimentation men 6 -12 mm/hour women 2 -14 mm/hour
Erythrocytes Respiratory Transport Alkaline-acidic balance Group
Sickle-cell anemia Normocyte 7, 1 -7, 9 mkm (75%) Macrocyte >8 mkm Microcyte <6 mkm Anisocytosis >20% abnormal sized cells Discocytes, planocytes, echinocytes… Poykilocytosis >25% abnormal shaped cells
Leucocytes
Leucocytes count % Granulocytes Bazo Eosino philic 0 -1 0. 5 -5 Agranulocytes Neutrophilic Band Juvenile Segmented 0. 5 - 1 -6 1 47 -72 Lymphocytes Mono cytes 19 -37 3 -11
Neutrophils
Neutrophil
Eosinophil
Eosinophil
Basophil
Basophil
Lymphocytes –immunocytes 1. Small, medium sized, large 2. EM: small light and dark, medium sized, B-plasma cells 3. T and B 4. Active and memory cells
Lymphocyte
Monocyte-mononuclear cell >20 mkm Bean-like nucleus Golgi apparatus =>lysosomes Active type - macrophage
Monocyte
Mononuclear macrophagic system
Platelet
HEMATOPOIESIS – blood components development (blood cells and plasma) Hematocytopoiesis: 1. Erythrocytopoiesis 2. Leucocytopoiesis a) granulocytopoiesis b) agranulocytopoiesis 3. Trombocytopoiesis
THEORIES OF HEMATOPOIESIS • POLYPHYLETIC THEORY – each mature blood cell type is derived from its own distinct stem cell • MONOPHYLETIC THEORY (A. A. Maximov) – there is one stem cell, which can form all the mature blood cells types • Multipotential stem cell (CFU -S – colony-forming-unit of spleen)
Scheme of hematopoiesis
Hematopoietic stem cell 1. Originates in the yolk sac 2. Thrives in RBM 3. Similar to small dark lymphocyte 4. Migrating cell 5. Pluripotential cell (gives rise to different cells) 6. Self-supporting cell 7. Rarely dividing cell (Go) 8. Sensitive cell
Differences between embryonic and postembryonic hematopoiesis Embryonic Postembryonic Histogenesis of blood Blood physiologic regeneration Extracorporal (extraembryonic) Intracorporal Intravascular Extravascular Occurs in different organs Megaloblastic erythropoiesis mesoblastic RBM Normoblastic
CLASSES OF HEMATOPOIETIC CELLS I class – polipotent (pluripotent) stem cell II class – hemistem cells for lymphocytopoiesis and myelopoiesis III class – unipotent cell (committed) sensitive to exact hemopoietin (erythropoietin, leykopoietin, thrombopoietin) IV class – blasts (young actively dividing cells) V class – maturing cells VI class – an “adult” mature cells in peripheral blood
Erythropoiesis 1. Decrease in cell size (from 20 till 8 мm) 2. Ejection (extrusion) of the nucleus 3. Accumulation of hemoglobin in the cytoplasm 4. Basophily decrease and acidophily increase
ERYTHROPOIESIS
GRANULOCYTOPOIESIS
GRANULOCYTOPOIESIS 1. Decrease in the cell size 2. Chromatin condensation 3. Changes in nuclear shape (flattening – indentation – lobulation). 4. Accumulation of cytoplasmic granules.
LYMPHOCYTOPOIESIS
LYMPHOCYTOPOIESIS 1. Begins in red bone marrow and then continues in lymphoid tissue 2. Lifespan varies in different types of lymphocytes 3. Antigenindependent development – in the central hematopoietic organs (red bone marrow and thymus) and antigendependent – in peripheral ones (spleen, lymph nodes and nodules)
MONOCYTOPOIESIS 1. Decrease in cell diameter 2. Decrease in nuclear diameter 3. Cytoplasm basophily decreases 4. Nucleus changes its shape from round to kidney-like
MONOCYTOPOIESIS
Trombocytopoiesis Megakaryocyte
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