BLOOD

1. Kharkov National Medical University BLOOD Department of histology, cytology and embryology 2013 medical students

2. Blood: consists of «Cells»: Erythrocytes (RBC) Leucocytes (WBC) Thrombocytes (Platelets) + Plasma (fluid intercellular space)

3. “Cells” of the BLOOD

4. Blood cells. Erythrocytes

5. ERYTHROCYTES Amount in blood Men - 3.9 - 5.5 ×1012/liter Women - 3,7-4,9 ×1012/liter

6. Erythrocyte : biconcavedisc withaveragediameter ~7 µm(!!!). does not contain a nucleus is filledwithhemoglobin - the oxygen binding protein

7. function of ERYTHROCYTE: carriesoxygenfromthelungstothebodycells, helps in carrying of CO2 from tissues to the lungs !!! NOTE: biconcave shape improves exchange by decreasing of diffusions distance !!!

8. ERYTHROCYTES erythrocytes abnormalities : • an erythrocyte, smaller than 6 µm in diameter is termed a microcyte; • whereas an erythrocyte larger than normal (from 9 µm to 12 µm in diameter) is termed a macrocyte • Thus a shift in size range toward smaller erythrocytes is called a microcytic condition, and toward bigger ones, a macrocytic condition.

9. Smears of normal blood usually exhibit an occasional erythrocyte of abnormal shape. The general term for such a cell is a poikilocyte (Gr. poikilis, manifold).

10. Unisocytosis and Poikilocytosis 1 — discocytes -normocytes; 2 — MACROCYTE; (may be microcyte, 2 types of un-iso-cytosis) 3,4 — echinocytes; 5 — stomatocyte; 6 — sferocytes. 3-6 - poikilocytosis 1 3 6 5

11. Platelets

12. Platelets They are: membrane-bound sacs, fragments of cells; 2 to 5 µm in diameter.

13. PLATELETS Platelets Play a Key Role in the Arrest of Bleeding (Hemostasis, blood clotting)

14. Platelets

15. Platelets Consist of 2 zones: - peripheral one is called the Hyalomere. The central one - Granulomere. Hyalomere is a colorless and homogeneous. granulomere contains azure-colored granules.

16. Platelets Thegranulescontainseveraldifferentsubstances: thromboplastin – promotesbloodclotting serotonin – elicitspain platelet-derivedgrowthfactor (PDGF) - stimulatestissueregeneration

17. Leucocytes True cells, have nucleus, organelles and inclusions in granules ALL Leucocytes migrare from blood to connective tissue Nucleus containes two to eight lobes

18. Classification:types by presence of granules!!! Totally 5 types of leucocytes Granulocytes neutrophils, basophils, eosinophils A-granulocytes • monocytes, • lymphocytes

19. Basophils

20. Basophils The basophilic granules are large, stain deep blue to purple, and are often so numerousthat they mask the nucleus. Basophils constitute only approximately 0.5% of peripheral blood leukocytes.

21. Basophils These granules contain histamine (cause vasodilation) and heparin (anticoagulant).

22. Eosinophils

23. Eosinophils have large acidophilic granules which appear pink (or red). The granules contain digestive enzymes that are particularly effective against parasitic worms These cells also phagocytize antigen-antibody complexes.

24. EosinophilsEM image

25. Neutrophils

26. Neutrophils 12 to 14 µm in diameter. Granulesare pale staining (neutral) They play primary role in inflammation. They are capable forphagocytosis of bacteria.

27. The segmented nucleus of most neutrophils consists of two to five lobes interconnected by fine strands of chromatin. In mature neutrophils, sex chromatin (where present) can sometimes be seen as a separate tiny lobe known as a drumstick appendage. The cytoplasm of mature neutrophils contains two kinds of granules azurophilic granules and specific granules

28. Neutrophil, phagocyte

29. Lymphocytes

30. LEUKOCYTES Lymphocytescomprise 20% to 50% of the blood leukocytes

31. Lymphocytes Nucleusisverylarge, almostfillsthecellleavingaverythinrimofcytoplasm. Function - immuneresponse. 2 types: TheB-lymphocytes:go to connective tissue to become PLASMA Cell.produceantibodies, TheT-lymphocytesactagainstvirus-infectedcellsandtumorcells.

32. Lymphocytes

33. Monocytes

34. Monocytes - arethe largestamongtheleukocytes,about 20 µmindiameterandagranular. ThenucleusismostoftenU-shapedorkidney-bean-shaped, orC-shaped thecytoplasmisabundantandlightblue. Monocytes comprise from 3% to 11% of the blood leukocytes

35. Monocytes Thesecellsleavethebloodstreamtobecomemacrophagesin conn. tiss. macrophagesplayaroleininflammatoryandimmuneresponses. are antigen-presenting cells(APC) Theyarephagocytes, defendthebodyagainstvirusesandbacteria.

36. Complete Blood Count (CBC)

37. White Blood Cell Differential Count

38. Blood Cell formation(haemocytopoiesis)

39. Haemopoiesis During fetal development, the formation of blood cells (haemopoiesis) begins inthewall of the yolk sac. After the second month of fetal development, the liver, and, slightly later, the spleen, become the dominant sites of haemopoiesis. From the 6th month the formation of blood cells occurs in bone marrow,

40. Haemopoietic Cells There are 6 classes of Haemopoietic Cells

41. 1 class Stem cells – 1-st class -- self-replicating, which can generate all types of blood cells.

42. 2 class Progeny of stem cells may develop into either lymphoid semi-stem cells (gives rise to lymphocytes) or myeloid semi-stem cells(gives rise to the major groups of blood cells other than lymphocytes)

43. Note: semi-stem cells: - are particularly determined cells: are capable to develop only into lymphocytes or only into all other blood cells. Development of blood cells from LSC is called lymphopoiesis. Development of blood cells from MSC is called myelopoiesis.

44. 3 class is called unipotential or … hemopoietin-sensitive cells.

45. Myeloid lines Myeloid semi-stem cell forms 4 kinds of hemopoietin-sensitive cells: Erythropoietin-sensitive cell forms the erythroid line Leukopoietin-sensitive cell forms granulocytes line Monopoietin-sensitive cell forms monocyte - macrophages line Thrombopoietin-sensitive cell forms megakaryocytes --- thrombocyteline

46. Lines of lymphopoiesis B- lymphopoiesis T- lymphopoiesis

47. 4-th class of Haemopoietic Cells The first recognizable, actively dividing cells that are called blast cells.

48. 4. Haemopoietic Cells There are six types of blast cells: Proerythroblast or simply erythroblast; Myeloblast; B- lymphoblast; Megakaryoblast; Monoblast T- lymphoblast;

49. 5th class of Haemopoietic Cells - cell differentiation

50. 6th class of Haemopoietic Cells Mature cell - leave RBM and Thymus and go to bloodstream