Blood and Its Components

RBC
WBC
1. Granulocytes
Neutrophils
Eosinophil’s
Basophils
2. Agranulocytes
Lymphocytes
Monocyte
PLATELETS
Blood is a bright red, viscous, slightly alkaline fluid that accounts for approximately 7 % of total body weightThe average human has 5 litres of blood (Average Blood Volume is 4 to 6 liters).
It is a transporting fluid.
Red colour is due to the presence of oxyhaemoglobin.
Ph - 7.4 slightly alkaline.
Specific gravity - 1.060
Viscosity is 5 times greater then the water i.e thicker than water.
Blood is the only fluid tissue.
Blood is a complex connective tissue in which living cells, the formed elements, are suspended in fluid componenet called plasma.
Functions of Blood
Transport of:
Gases, nutrients, waste products
Processed molecules
Regulatory molecules.
Regulation of pH and osmosis.
Maintenance of body temperature.
Protection against foreign substances.
Clot formation.
Blood composition

55% Plasma (fluid matrix of water, salts, proteins, etc.)
45% Cellular elements:
Red Blood Cells (RBCs) (Erythrocytes) : 5-6 million RBCs/ml of blood.
Contain hemoglobin which transport oxygen and CO2.

White Blood Cells (WBCs) (Leukocytes) : 5,000-10,000 WBCs/ml of blood.
Play an essential role in immunity and defense.
Include:
Granulocytes
Neutrophils 40-70%
Eosinophil's 0-1%
Basophils 1-5%
Agranulocytes
Lymphocytes 25-40% T cells and B cells
Monocyte 2-8% (phagocytes)

Platelets (Thrombocytes) : Cellular fragments, 250,000- 400,000/ml of blood.
Important in blood clotting.

1. Blood and Its Components Dr Amitha G, BDS, MDS Oral and maxillofacial Pathology

2. Contents: Introduction RBC WBC 1. Granulocytes Neutrophils Eosinophil’s Basophil s 2. Agranulocytes Lymphocytes Monocyte PLATELETS

3. Blood Blood is a bright red, viscous, slightly alkaline fluid that accounts for approximately 7 % of total body weight

4. Introduction:- The average human has 5 litres of blood ( Average Blood Volume is 4 to 6 liters). It is a transporting fluid. Red colour is due to the presence of oxyhaemoglobin . Ph - 7.4 slightly alkaline. Specific gravity - 1.060 Viscosity is 5 times greater then the water i.e thicker than water. Blood is the only fluid tissue . Blood is a complex connective tissue in which living cells, the formed elements, are suspended in fluid componenet called plasma.

5. Functions of Blood Transport of: Gases, nutrients, waste products Processed molecules Regulatory molecules. Regulation of pH and osmosis. Maintenance of body temperature. Protection against foreign substances. Clot formation.

6. Blood composition 55% Plasma (fluid matrix of water, salts, proteins, etc.) 45% Cellular elements: Red Blood Cells (RBCs) (Erythrocytes) : 5-6 million RBCs/ml of blood. Contain hemoglobin which transport oxygen and CO 2 . White Blood Cells (WBCs) (Leukocytes ) : 5,000-10,000 WBCs/ml of blood. Play an essential role in immunity and defense. Include : Granulocytes Neutrophils 40-70% Eosinophil's 0-1% Basophils 1-5% Agranulocytes Lymphocytes 25-40% T cells and B cells Monocyte 2-8% (phagocytes) Platelets (Thrombocytes ) : Cellular fragments, 250,000- 400,000/ml of blood. Important in blood clotting.

7. Plasma Straw-colored liquid. Consists of h 2 0 and dissolved solutes. Ions, metabolites, hormones, antibodies. Na + is the major solute of the plasma. Liquid part of blood Plasma transports Soluble food molecules Waste products Hormones Antibodies

8. Plasma ORIGIN OF PLASMA PROTEINS Embryo Mesenchyme cells Albumin synthesized first Adults Reticuloendothelial cells of liver Spleen, bone marrow, disintegrating blood cells, tissue cells Gamma globulin synthesized from B lymphocytes

9. Plasma Proteins Constitute 7-9% of plasma Three types of plasma proteins: albumins, globulins, & fibrinogen Albumin accounts for 60-80, plasma protein made by the liver, Creates colloid osmotic pressure that draws H 2 0 from interstitial fluid into capillaries to maintain blood volume & pressure Globulins carry lipids and are produced by lymphocytes. a globulin: Transport lipids and fat soluble vitamins. b globulin: Transport lipids and fat soluble vitamins. g globulin: Antibodies that function in immunity.

10. Gamma globulins are antibodies Fibrinogen Constitutes 4% of plasma proteins. Important clotting factor. Converted into fibrin during the clotting process. Serum is fluid left when blood clots

11. FUNCTION: Coagulation of blood Defence mechanism Role in Transport mechanism Maintanance of osmotic pressure of blood Acid base regulation Viscosity of blood Erythrocyte sedimentation rate

12. Erythrocytes / RBC 7-8 m diameter Biconcave disc shape  surface area  efficiency for diffusion of O2 & CO2 Flexible Elastic 100-120 day life span Originate in bone marrow Structure Plasma membrane Cytoplasm Hemoglobin Binds O 2 & CO 2 No nucleus or organelles

13. Biconcave shape: Rapid diffusion Large surface area Minimal tension Squeeze through capillaries Properties of RBS’s: Rouleaux formation Specific gravity : 1.092 to 1.101. Packed cell volume Suspension stability

14. Life span and fate of rbc’s Average life span -- about 120 days. Spleen -- Graveyard of red blood cells. Daily 10% red blood cells, which are senile, get destroyed in normal young healthy adults.

15. Leukocytes or white blood cells ( wbcs ) Complete cells (nuclei, mitochondria and organelles) Move in amoeboid fashion. Can squeeze (leave the blood vessels through) capillary walls ( diapedesis ), respond to chemicals Almost invisible, so named after stains. Neutrophils are the most abundant WBC, accounts for 50 – 70% of WBCs.

16. Involved in immune function. Crucial for defense. Positive chemotaxis: they respond to chemical signals and move toward damage or threats. Body increases amount in response to infection Leukocytosis: more than 11,000 cells/mm3 indicates infection Leukopenia: abnormally low, usually due to corticosteroids and chemotherapy.

17. Granulocytes Neutrophils Multi-lobed nucleus with fine granules Act as phagocytes at active sites of infection Eosinophils Large brick-red cytoplasmic granules Found in response to allergies and parasitic worms Basophils Have histamine-containing granules Initiate inflammation

18. Agranulocytes are phagocytic & produce antibodies Include lymphocytes & monocytes Lymphocytes Nucleus fills most of the cell Play an important role in the immune response Increase in lymphocytes counts is seen in : Diptheria Infectious hepatitis Mumps Malnutrition Rickets Syphilis Tuberculosis

19. Monocytes: Monocytes Largest of the white blood cells Function as macrophages Important in fighting chronic infection Increase in monocytes seen in Tuberculosis Syphilis Malaria Glandular fever

20. Have nucleus, mitochondria, & amoeboid ability Can squeeze through capillary walls ( diapedesis ) Granular leukocytes help detoxify foreign substances & release heparin Include eosinophils , basophils , & neutrophils

21. Neutrophils [ Polymorphonuclear leukocytes] Constitute 60 – 70% 12 – 15 µm in diameter in blood smear Nuclei having two to five lobes Cytoplasm contains abundant specific granules and azurophilic granules Short lived with a half life of 6 – 7hrs in blood and a life span of 1 – 4 days in connective tissue(terminal cell) 23

22. Neutrophils [ Polymorphonuclear Leukocytes] Specific granules: 1) Azurophilic (primary) : cathepsin , elastase , aryl sulphatase , acid phosphatase 2)Specific (secondary): alkaline phosphatase, lysozyme, collagenase, lactoferrin , NADPH oxidase 3) Tertiary : gelatinase , cethepsins , glycoprotein that are inserted into plasmalemma 24

23. Neutrophils [ Polymorphonuclear Leukocytes] Specific granules: contains varies enzymes and pharmacological agents that aid the neutrophil in performing its antimicrobial functions. In EM granules appear oblong Azurophilic granules: as already indicated, are lysosomes, containing acid hydrolysis, myeloperoxidase, antibacterial agent lysozyme, bacterial permeability increasing protein, cethepsin G, Elastase , Nonspecific collagenase Tertiary granules: contain gelatinase and cethepsins as well as glycoprotein that are inserted into plasmalemma 25

24. Neutrophils [ Polymorphonuclear Leukocytes] 26

25. Neutrophils [ Polymorphonuclear Leukocytes] 27

26. Neutrophils [ Polymorphonuclear Leukocytes] Functions : Considered as defence against invasion of micro organisms Active phagocytes of small particles and are termed microphages 28

27. Neutrophils An increased percentage of neutrophils may be due to: Acute infection Metabolic disorders Injection of foreign proteins Acute haemmorhage Rheumatoid arthritis Rheumatic fever Thyroiditis Trauma A decreased percentage of neutrophils may be due to: Aplastic anemia Chemotherapy Influenza Radiation therapy or exposure Viral infection Widespread severe bacterial infection 29

28. Eosinophils Constitute 2-4% of leukocytes Same size(12-15) as neutrophil Nucleus is bilobed Abundance of large, specific granules( abt 200 per cell)stained by eosin Survive for 2 to 5 days 30

29. Specific granules: Acid phosphatase Arylsulfatase Beta- glucoranidase Cathepsin Phospholipase RNAase Eosinophilic peroxidase Major basic protein

30. Eosinophils Eosinophils are responsible for detoxification, disintegration and removal of foreign proteins . The lethal substances present in the granules of eosinophils and released at the time of exposure to parasites or foreign proteins are: Internum : 1. Major basic protein (MBP) [50%]: arginin,histaminase 2. Eosinophil cationic protein (ECP) 3. Eosinophil-derived neurotoxin Externum : Chemotactic factor receptor 32

31. Eosinophil 33

32. Eosinophil 34

33. Eosinophils Functions: Involved in immediate type of hypersensitivity. Granules release enzymes capable of degrading chemical mediaters of inflammation. Produce histaminase which inactivates histamine. Count is increased in parasitic infection. 35

34. Eosinophils Reduced eosinophil count is seen in Bacterial infection Cushing syndrome or use of steroids Burns and acute infections 36

35. Eosinophils An increased percentage of eosinophils may be due to: Asthma Allergic condition Collagen vascular disease Scarlet fewer Parasitic infection 37

36. Basophils 12 – 15 µm in diameter Make up 1% of blood leukocytes Nucleus is S shaped Supplement the function of mast cells Survive for 60 to 70 hrs Specific granules consists of: Eosinophilic chemotactic factor Heparin Histamine Peroxidase 38

37. Basophils 39

38. Basophils 40

39. Basophils Functions : Increased in allergic inflammation Cause release of histamine, SRS-A. Cell membrane bears the fc receptors that have affinity for plasma Ig E- basophil is sensitized with Ig E Increased by certain harmones like cortisol Reduced count is seen in urticaria 41

40. Basophils An increased percentage of basophils may be due to: Small pox Chicken pox Polycytemia vera Allergic reaction Collagen vascular disease Varicella infection A decreased percentage of basophils may be due to: Acute infection Cancer Severe injury 42

41. Function of T cells : secrete lymphokines induction of apoptosis in target cells create pores in target cells Function of B cells : produce plasma cells- immmunoglobins Nk cells/ large granular lymphocytes attack cancer cells and viruses

42. Platelets Also called thrombocytes. Derived from ruptured multinucleate cells (megakaryocytes) Smallest of formed elements. Are fragments of megakaryocytes. Lack nuclei. Normal platelet count = 300,000/mm 3 Survive 5-9 days Have amoeboid movement. Important in blood clotting: Constitute most of the mass of the clot. Release serotonin to reduce blood flow to area. Secrete growth factors Maintain the integrity of blood vessel wall.

43. PROPERTIES OF PLATELETS 1. ADHESIVENESS collagen, thrombin, ADP, Thromboxane A 2 , calcium ions and von Willebrand factor. 2. AGGREGATION (GROUPING OF PLATELETS) ADP and thromboxane A2 . 3. AGGLUTINATION Platelet agglutinins.

44. Functions :- Blood coagulation Form temporary haemostatic plug Sealing blood vessels Clot retraction Phagocytic function Storage & transport of 5-HT & histamine Repair of blood vessel.

45. Thank you Dr Amitha G