1. Blood Physiology Professor A.M.A Abdel Gader MD, PhD, FRCP (Lond., Edin), FRSH (London) Professor of Physiology, College of Medicine & King Khalid University Hospital Riyadh

3. Lecture # 4 & 5 Leucocytes White Blood Cells (WBCs) Granulocytes, The Monocyte-Macrophage System

4. Leucocytes (WBCs) General Characteristics & types of WBCs Genesis (Production) of WBCs Life Span of WBCs Defense properties of neutrophils & macrophages –Chemotaxis –Diapedesis –Amaeboid Motion –Phagocytosis

5. Blood Film

7. Hematopoiesis

8. Leucocytes (WBCs) – cont. General Characteristics & types of WBCs Types of WBC 1.Granular (polymorphnuclear): Neutrophil 62%. –10-16um, nucleus 2-5 lobes, purple cytoplasmic granules Eosinophil 2.3%. –12-18um, 2 lobes nucleus, coarse red granules Basophil.4%. –10-14um, rarely segmented nucleus, nucleus hidden by large round bluish granules

9. Leucocytes (WBCs) – cont. General Characteristics & types of WBCs Types of WBC 2.Agranular WBC –Monocytes 5.3% 15-20um, kidney shape nucleus –Lymphocyte 30% round nucleus –small (5-8um) –large (9-15um)

10. Formed Elements of Blood Red blood cells ( erythrocytes ) White blood cells ( leukocytes ) –granular leukocytes neutrophils eosinophils basophils –agranular leukocytes lymphocytes = T cells, B cells, and natural killer cells monocytes Platelets

11. Leucocytes (WBCs) – cont. Genesis (Production) of WBCs Pluripotential stem cell Committed Stem cell RBCs WBCs Platelets MylocyticLymphocytic Linage

12. Hematopoiesis

13. Leucocytes (WBCs) – cont. Genesis (Production) of WBCs- leucopoiesis) Sites of WBC formation Granulocytes (neutrophil, basophil, eosinophil): –bone marrow Agranulocytes –lymphocytes- bone marrow, thymus, lymphoid tissues –monocytes- bone marrow

14. Life Span of WBCs Granulocytes: 4 to 8 hrs (transit time ) in blood circulation 4 to 5 hrs in tissues –In infections life span a few hours Monocytes : –10 to 20 hrs in blood circulation –Leave capillaries to tissues, increase in size to become tissue macrphages which live for months

15. Life Span of WBCs- cont. Lymphocytes: A few hrs in blood circulation >> tissues >> lymph >>> Blood (Recirculation) ?Life span: weeks to months

16. Leucocytes (WBCs) General Characteristics & types of WBCs Genesis (Production) of WBCs Life Span of WBCs Defense properties of neutrophils & macrophages –Chemotaxis –Diapedesis –Amaeboid Motion –Phagocytosis

17. Defense properties of neutrophils & macrophages Attack and destroy bacteria, viruses Sequence of events: –Chemotaxis –Diapedesis –Amaeboid Motion –Phagocytosis

19. Netrophils function-cont. Defense properties of neutrophils & macrophages- cont Phyagocytosis: Engulfing and killing of bacteria or any invading organism Steps: Chemotaxis: –Bacterial & viral toxins Products of damaged tissues : attract neutrophil to accumulate at infected site. –Opsonization: plasma substances (IgG) attached to the bacteria to make them easy to phagocyte

20. Diapedesis

21. http://www.whfreeman.com/immunology/CH01/diapedesis.htm

22. Defense properties of neutrophils & macrophages Attack and destroy bacteria, viruses Sequence of events: –Chemotaxis –Diapedesis –Amaeboid Motion –Phagocytosis

24. Defense properties of neutrophils & macrophages Attack and destroy bacteria, viruses Sequence of events: –Chemotaxis –Diapedesis –Amaeboid Motion –Phagocytosis

25. Phagocytosis- cont. Phagocytosis is selective: Distinguish self from non-self…... How? –Normal tissues have smooth surface –Normal tissues have protective protein surface –Antibodies coating bacteria ( Opsonization)

26. Phagocytosis

27. Phagocytosis by neutrophils- cont. Neutrophils attach to bacteria & encircled it with pseudopodia and take it into a vacuole (phagosome). One Neutrophil can engulf 3 to 20 bacteria One Macrophage can engulf up to 100 bacteria Microbial killing: fusion of neutrophil granules with vacuole, –Discharge of lysozyme, myeloperoxidase enzymes into the vacuole, killing and digesting the engulfed bacteria. –Release of Free radicals by oxidizing agents: superoxide, hydrogen peroxide to kill the bacteria

29. Leucocytes (WBCs) – cont. Types of WBC 1.Granular (polymorphnuclear): Neutrophil 62%. –10-16um, nucleus 2-5 lobes, purple cytoplasmic granules Eosinophil 2.3%. –12-18um, 2 lobes nucleus, coarse red granules Basophil.4%. –10-14um, rarely segmented nucleus, nucleus hidden by large round bluish granules

30. Blood Film

31. Eosinophils Function: Phagocytosis: Phagocytosis is same as neutrophil, but less efficient Chemotaxis: eosinophil attracted towards chronic inflammation/allergic tissue ( allergic disease of skin & lungs) By eosinophil chemotactic factor Phagocytose (& detoxify) antigen/antibody complexes

32. Eosinophils cont, High eosinophil count: –Parasitic (hook worm, ascaris, bilharzia) –Allergic (asthma, rhinitis, drug reaction) –Allergic skin diseases

33. Leucocytes (WBCs) – cont. Types of WBC 1.Granular (polymorphnuclear): Neutrophil 62%. –10-16um, nucleus 2-5 lobes, purple cytoplasmic granules Eosinophil 2.3%. –12-18um, 2 lobes nucleus, coarse red granules Basophil.4%. –10-14um, rarely segmented nucleus, nucleus hidden by large round bluish granules

34. Leucocytes (WBCs) – cont. Types of WBC 1.Granular (polymorphnuclear): Neutrophil 62%. –10-16um, nucleus 2-5 lobes, purple cytoplasmic granules Eosinophil 2.3%. –12-18um, 2 lobes nucleus, coarse red granules Basophil.4%. –10-14um, rarely segmented nucleus, nucleus hidden by large round bluish granules

35. Blood Film

36. Basophils Similar to tissue mast cells Non-phagocytic cells Granules: dark blue color. Granules contain: –Heparin –Histamine –Serotonin (5HT). Released during allergic reactions

37. Hematopoiesis

38. Blood Film

40. Defensive Functions of the Monocytes Directly: –phygocytosis of bacteria, dead cells etc Indirectly: –Cooperates with lymphocytes by: Recognizing the foreign body Ingesting the foreign body Processing the foreign body Presenting it to lymphocytes

41. Monocyte-macrophage system Reticulo-endothelial System

42. Reticuloendothelial System- RES Blood Monocyte Tissue macrophage Attached (fixed) Mobile Function is phagocytosis of: Bacteria Viruses Dead tissues Foriegn particles Immune function

43. Reticuloendothelial System- RES RES is widespread in the body Cells of the RES: –Monocytes (blood macrophages) –Mobile and fixed tissue Macrophages –Specialiazed endothelial cells in bone marrow, ly mph nodes and spleen –Reticular cells of lymph nodes spleen & bone marrow.

44. Reticuloendothelial System- RES Cells of the RES - Distribution: Tissue Macrophages in skin SC tissues Tisssue Macrophages of lymph nodes Tissue macrophages in lungs Macrphages (kupffer cells) in the liver Macrphages in the spleen and bone marrow

45. Reticuloendothelial System- RES Blood Monocyte Tissue macrophage Attached (fixed) Mobile Function is phagocytosis of: Bacteria Viruses Dead tissues Foriegn particles Immune function