BIOH122 Human Biological Science 2

Transcription

1 BIOH122 Human Biological Science 2 Session 1 Haematological System Blood and the Elements Bioscience Department Endeavour College of Natural Health endeavour.edu.au

2 Session Plan o o o o Blood Functions Properties Components Haematopoiesis Haemopoietic growth factors Red Blood Cells Functions Properties Haemoglobin Erythropoiesis Life cycle White Blood Cells Properties Classification Functions Endeavour College of Natural Health endeavour.edu.au 2

3 Blood Endeavour College of Natural Health endeavour.edu.au 3

4 Fluids of the Body o Cells of the body are serviced by two fluids Blood composed of plasma and a variety of cells transports nutrients and wastes Interstitial fluid bathes the cells of the body o Nutrients and oxygen diffuse from the blood into the interstitial fluid and then into the cells o Wastes move in the reverse direction Endeavour College of Natural Health endeavour.edu.au 4

5 Components of Blood Endeavour College of Natural Health endeavour.edu.au 5

6 Functions of Blood o Transportation O2, CO2, metabolic wastes, nutrients, heat and hormones o Regulation helps regulate ph through buffers helps regulate body temperature coolant properties of water vasodilatation of surface vessels dump heat helps regulate water content of cells by interactions with dissolved ions and proteins o Protection from disease and loss of blood Endeavour College of Natural Health endeavour.edu.au 6

7 Physical Characteristics of Blood o Viscosity: Thicker (more viscous) than water Temperature: of 38 degrees C (100.4 degrees F) o ph: Alkaline 7.4 (range ph) o 8 % of total body weight o Blood volume: 5 to 6 liters in an average male 4 to 5 liters in an average female hormonal negative feedback systems maintain constant blood volume and osmotic pressure Endeavour College of Natural Health endeavour.edu.au 7

8 Techniques of Blood Sampling o Venipuncture sample taken from a vein with a hypodermic needle and syringe median cubital vein why not stick an artery? less pressure in veins veins are closer to the surface o Finger or heel stick common technique for diabetics to monitor daily blood sugar method used for infants m.com&login=ever2178 Endeavour College of Natural Health endeavour.edu.au 8

9 Components of Blood o Blood consists of: o plasma 55% o formed elements 45% o Blood plasma consists of: 91.5% water and 8.5% solutes. o Principal solutes include proteins (albumins, globulins, fibrinogen), nutrients, enzymes, hormones, respiratory gases, electrolytes, and waste products. Endeavour College of Natural Health endeavour.edu.au 9

10 Components of Blood Endeavour College of Natural Health endeavour.edu.au 10

11 o Water: 0ver 90% o Plasma proteins: 7% Blood Plasma created in liver confined to bloodstream o Other substances: 2% electrolytes, nutrients, hormones, gases, waste products Endeavour College of Natural Health endeavour.edu.au 11

12 Blood Plasma Proteins o Albumin maintain blood osmotic pressure o Globulins (immunoglobulins) antibodies bind to foreign substances called antigens form antigen-antibody complexes o Fibrinogen for clotting Endeavour College of Natural Health endeavour.edu.au 12

13 Formed Elements of Blood o Red blood cells (erythrocytes) o White blood cells (leukocytes) granular leukocytes neutrophils, eosinophils, basophils agranular leukocytes lymphocytes = T cells, B cells, and Natural Killer cells monocytes o Platelets (Thrombocytes) Endeavour College of Natural Health endeavour.edu.au 13

14 Formed Elements of Blood Endeavour College of Natural Health endeavour.edu.au 14

15 Haematopoiesis Endeavour College of Natural Health endeavour.edu.au 15

16 Formation of Blood Cells o Blood cells are formed from pluripotent haematopoietic stem cells o The pluripotent stem cells differentiated into: Myeloid stem cells Lymphoid stem cells. o Bone marrow Examination: Through Aspiration or biopsy The sample is then sent to pathology for examination. Endeavour College of Natural Health endeavour.edu.au 16

17 Formation of Blood Cells o Hematopoiesis/haemopoiesis: Process of formed elements of blood/blood cell development Most blood cell types need to be continually replaced as die within hours, days or weeks o In the embryo occurs in yolk sac, liver, spleen, thymus, lymph nodes and red bone marrow o In the adult occurs only in red marrow of flat bones like sternum, ribs, skull and pelvis and ends of long bones Endeavour College of Natural Health endeavour.edu.au 17

18 Haematopoiesis Endeavour College of Natural Health endeavour.edu.au 18

19 Stages of Blood Cell Formation o Pluripotent stem cells: 1% of red marrow cells Replenish themselves as they differentiate into either myeloid or lymphoid stem cells Endeavour College of Natural Health endeavour.edu.au 19

20 Myeloid Stem Cells o Myeloid stem cell line of development continues: progenitor cells (colony-forming units) no longer can reproduce themselves and are committed to form specific cell types example: CFU-E develops eventually into only red blood cells blast cells are next generation cells have recognizable histological characteristics develop within several divisions into mature cell types including RBCs, platelets, and all WBCs except for lymphocytes Endeavour College of Natural Health endeavour.edu.au 20

21 Lymphoid Stem Cells o Lymphoid stem cell line of development continues: pre-b cells and prothymocytes finish their development into B and T lymphocytes in the lymphatic tissue after leaving the red marrow Endeavour College of Natural Health endeavour.edu.au 21

22 Haemopoietic Growth Factors o Stimulate and regulate differentiation and proliferation of the various blood cells. o Erythropoietin (EPO) produced by the kidneys increase RBC precursors o Thrombopoietin (TPO) hormone from liver stimulates platelet formation o Cytokines local hormones of bone marrow produced by some marrow cells to stimulate proliferation in other marrow cells Endeavour College of Natural Health endeavour.edu.au 22

23 Medical Uses of Growth Factors o Available through recombinant DNA technology recombinant erythropoietin (EPO) very effective in treating decreased RBC production of end-stage kidney disease thrombopoietin helps prevent platelet depletion during chemotherapy other products given to stimulate WBC formation in cancer patients receiving chemotherapy which kills bone marrow Endeavour College of Natural Health endeavour.edu.au 23

24 Red Blood Cells Endeavour College of Natural Health endeavour.edu.au 24

25 Red Blood Cells or Erythrocytes o Size: 8 microns in diameter o Shape: Biconcave disc increases surface area/volume ratio o Structure: flexible plasma membrane for narrow passages no nucleus or other organelles no cell division or mitochondrial ATP formation o Surface antigens: AB antigens o Haemoglobin: oxygen-carrying protein in cytosol that gives blood its red colour 1/3 of cell s weight is haemoglobin Endeavour College of Natural Health endeavour.edu.au 25

26 RBC Count o Normal RBC count: Male: 5.4 million/µl Female: 4.8 million/µl o New RBCs enter circulation at 2 million/second Endeavour College of Natural Health endeavour.edu.au 26

27 Haematocrit - Normal o Haematocrit/ Packed cell volume (PCV) o Percentage of blood occupied by Red blood cells Female normal range: 38-46% (average of 42%) Male normal range: 40-54% (average of 46%) increased by testosterone Endeavour College of Natural Health endeavour.edu.au 27

28 Haematocrit - Abnormal o Anaemia not enough RBCs or not enough haemoglobin o Polycythaemia too many RBCs (over 65%) dehydration, tissue hypoxia, blood doping in athletes, also primary polycythaemia Endeavour College of Natural Health endeavour.edu.au 28

29 Haemoglobin o Haemoglobin: Haeme+ Globin o Globin: protein consisting of 4 polypeptide chains o Haeme: One haeme pigment attached to each polypeptide chain each haeme contains an iron ion (Fe+2) that can combine reversibly with one oxygen molecule Endeavour College of Natural Health endeavour.edu.au 29

30 Haemoglobin Endeavour College of Natural Health endeavour.edu.au 30

31 Haemoglobin: Function o Transport of O 2, C O 2 and Nitric Oxide o O 2 : Each haemoglobin molecule can carry 4 O 2 molecules from lungs to tissue cells Combine with Fe2+ present at the centre of haeme o CO 2 : Haemoglobin transports 23% of total CO2 waste from tissue cells to lungs for release combines with amino acids in globin portion of Hb Endeavour College of Natural Health endeavour.edu.au 31

32 Haemoglobin-Normal o Normal haemoglobin range: Infants:14 to 20 g/100ml of blood Adult females: 12 to 16 g/100ml of blood Adult males: 13.5 to 18g/100mL of blood Endeavour College of Natural Health endeavour.edu.au 32

33 Haemoglobin- Abnormal o Deficiency of nutrients may lead to decrease production of Haemoglobin Iron deficiency anaemia Megaloblastic anaemia (Vit B12 or Folic acid deficiency) o Production of abnormal haemoglobin can result in serious blood disorders such as thalassaemia and sickle cell anaemia. o The blood test, haemoglobin A1c, can be used to monitor blood glucose levels in diabetics Endeavour College of Natural Health endeavour.edu.au 33

34 RBC Life Cycle o RBCs live only 120 days wear out from bending to fit through capillaries no repair possible due to lack of organelles o Worn out cells removed by fixed macrophages in spleen and liver o Important that RBC components are recycled Endeavour College of Natural Health endeavour.edu.au 34

35 Recycling of Haemoglobin Components Endeavour College of Natural Health endeavour.edu.au 35

36 Recycling of Haemoglobin Components o In macrophages of liver or spleen Globin portion broken down into amino acids and recycled Haeme portion split into iron (Fe+3) and biliverdin (green pigment) Endeavour College of Natural Health endeavour.edu.au 36

37 o Iron (Fe+3) Fate of Components of Haeme transported in blood to liver or bone marrow attached to transferrin protein (an iron transfer carrying protein) stored in liver, muscle or spleen attached to ferritin protein (an iron storage protein) o Biliverdin (green) converted to bilirubin (yellow). o Bilirubin secreted by liver into bile converted to urobilinogen then stercobilin (brown pigment in faeces) by bacteria of large intestine if reabsorbed from intestines into blood is converted to a yellow pigment, urobilin and excreted in urine (yellow pigment of urine) Endeavour College of Natural Health endeavour.edu.au 37

38 Erythropoiesis: Production of RBCs o Erythropoiesis: Erythrocyte formation, occurs in adult red bone marrow of certain bones. o The main stimulus for erythropoiesis is hypoxia. From anaemia, blood loss, circulatory problems. o Process: o Proerythroblast starts to produce Hb. o Reticulocyte is formed. o Reticulocytes leave bone marrow into the blood. (0.5% to 1.5% of RBC s) o In 1-2 days, they eject the remaining organelles to become a mature RBC. Endeavour College of Natural Health endeavour.edu.au 38

39 Feedback Control of RBC Production Kidney response to hypoxia release erythropoietin speeds up development of proerythroblasts into reticulocytes (people with Chronic Kidney Disease are also likely to be anaemic) Endeavour College of Natural Health endeavour.edu.au 39

40 White Blood Cells Endeavour College of Natural Health endeavour.edu.au 40

41 White Blood Cells or Leukocytes o Structure: nucleated cells and do not contain haemoglobin. o Surface antigens: major histocompatibility antigens (MHC), and are unique for each person (except for identical siblings) and can be used to identify a tissue. MHC antigens are present on all nucleated cells Erythrocytes don t have MHC antigens, but they have AB antigens. Basis for ABO Blood Group Endeavour College of Natural Health endeavour.edu.au 41

42 White Blood Cells Endeavour College of Natural Health endeavour.edu.au 42

43 WBC Classification o Based on presence of cytoplasmic granules: Granulocytes: Neutrophils Eosinophils Basophils Granules are made visible by staining Agranulocytes: Monocytes Lymphocytes Endeavour College of Natural Health endeavour.edu.au 43

44 Neutrophils (Granulocyte) o Nucleus: 2 to 5 lobes connected by thin strands o Diameter: microns o Granules are small o 60-70% of circulating WBCs Endeavour College of Natural Health endeavour.edu.au 44

45 Neutrophil Function o Fastest response of all WBC to bacteria o Direct actions against bacteria release lysozymes which destroy/digest bacteria release defensin proteins that act like antibiotics and poke holes in bacterial cell walls destroying them release strong oxidants (bleach-like, strong chemicals) that destroy bacteria 45 Endeavour College of Natural Health endeavour.edu.au 45

46 Basophils (Granulocyte) o Nuclei: Irregular, s-shaped, bi-lobed nuclei o Granules: Large, dark purple, Diameter: is 8 to 10 microns o Less than 1% of circulating WBCs Endeavour College of Natural Health endeavour.edu.au 46

47 Basophil Function o Involved in inflammatory and allergy reactions o Leave capillaries and enter connective tissue as mast cells o Release heparin, histamine and serotonin heighten the inflammatory response and account for hypersensitivity (allergic) reactions Endeavour College of Natural Health endeavour.edu.au 47

48 Eosinophils (Granulocyte) o Nucleus: 2 or 3 lobes connected by a thin strand o Granules: Large, uniform-sized, o Diameter: 10 to 12 microns o 2-4% of circulating WBCs Endeavour College of Natural Health endeavour.edu.au 48

49 Eosinophil Function o Leave capillaries to enter tissue fluid o Release histaminase slows down inflammation caused by basophils o Attack parasitic worms o Phagocytize antibody-antigen complexes Endeavour College of Natural Health endeavour.edu.au 49

50 Lymphocyte (Agranulocyte) o Nucleus: Dark, oval to round nucleus o Cytoplasm: sky blue in colour o Diameter: Small or Large Cell types Increase in number during viral infections o 20-25% of circulating WBCs Endeavour College of Natural Health endeavour.edu.au 50

51 Lymphocyte Functions o B cells destroy bacteria and their toxins turn into plasma cells that produces antibodies o T cells attack viruses, fungi, transplanted organs, cancer cells and some bacteria o Natural Killer cells attack many different microbes and some tumour cells destroy foreign invaders by direct attack Endeavour College of Natural Health endeavour.edu.au 51

52 Monocyte (Agranulocyte) o Nucleus: is kidney or horse-shoe shaped o Cytoplasm: is a foamy blue-gray o Diameter:12-20 microns, Largest WBC in circulating bl o 3-8% of circulating WBCs o Does not remain in blood long before migrating to the tis Endeavour College of Natural Health endeavour.edu.au 52

53 Monocyte Function o Migrate from the blood into the tissues, enlarge and differentiate into macrophages fixed macrophages: Found in specific tissues alveolar macrophages in lungs Kupffer cells in liver wandering macrophages: Rome the tissues and gather at sites of infection Take longer to get to site of infection, but arrive in larger numbers Destroy microbes and clean up dead tissue following an infection Endeavour College of Natural Health endeavour.edu.au 53

54 Function of WBCs: Immunity o Different WBCs combat inflammation and infection in different ways. Neutrophils and wandering or fixed macrophages (which develop from monocytes) do so through phagocytosis. Eosinophils combat the effects of histamine in allergic reactions, phagocytize antigen-antibody complexes, and combat parasitic worms. Basophils develop into mast cells that liberate heparin, histamine, and serotonin in allergic reactions that intensify the inflammatory response. Endeavour College of Natural Health endeavour.edu.au 54

55 Function of WBCs B lymphocytes: in response to the presence of foreign substances called antigens, differentiate into tissue plasma cells that produce antibodies. Basis for Antibody Mediated Immunity T lymphocytes: destroy foreign invaders directly. Responsible for killing cells. Responsible for Cell Mediated Immunity. Endeavour College of Natural Health endeavour.edu.au 55

56 Emigration and Phagocytosis in WBCs o WBCs leave the blood stream by emigration o Some WBCs, particularly neutrophils and macrophages, are active in phagocytosis. o The chemical attraction of WBCs to a disease or injury site is termed chemotaxis. Endeavour College of Natural Health endeavour.edu.au 56

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58 Total WBC Count o Less numerous than RBCs o Normal range: 5,000 to 10,000 cells per µl of blood 1 WBC for every 700 RBCs o Leukocytosis is a high white blood cell count microbes, strenuous exercise, anesthesia or surgery o Leukopenia is low white blood cell count radiation, shock or chemotherapy o Only 2% of total WBC population is in circulating blood at any given time rest are in lymphatic fluid, skin, lungs, lymph nodes and spleen Endeavour College of Natural Health endeavour.edu.au 58

59 Differential WBC Count o A diagnostic test in which specific white blood cells are quantified. o Differential count is useful in diagnosis type of infection, type of immune response or disease process. Normal differential range: Neutrophils 60-70% Lymphocyte 20-25% Monocytes 3-8 % Eosinophil 2-4 % Basophil <1% Endeavour College of Natural Health endeavour.edu.au 59

60 Complete Blood Count Complete Blood Count: Screens for anemia and infection o Includes: Total RBC, WBC and platelet counts Differential WBC Haematocrit and haemoglobin measurements Endeavour College of Natural Health endeavour.edu.au 60

61 Differential WBC Count Endeavour College of Natural Health endeavour.edu.au 61

62 Readings and Resources o Tortora, GJ & Derrickson, B Principles of Anatomy and Physiology, 14th edn, Wiley. o Harris, P, Nagy, S & Vardaxis, N 2010, Mosby s Dictionary of Medicine, Nursing and Health Professions, 2nd edn, Mosby Elsevier. o Guyton, AC & Hall, JE 2011, Textbook of Medical Physiology, 12th edn, Saunders Elsevier. o Marieb, EN & Hoehn, K 2010, Human Anatomy and Physiology, 8th edn, Benjamin Cummings Pearson. o Moore, KL, Dalley, AF & Agur, AMR 2010, Clinically Orientated Anatomy, 6th edn, Lippincott, Williams & Wilkins. Endeavour College of Natural Health endeavour.edu.au 62

63 Copyright COMMONWEALTH OF AUSTRALIA Copyright Regulations 1969 WARNING This material has been reproduced and communicated to you by or on behalf of the Endeavour College of Natural Health pursuant to Part VB of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Do not remove this notice. Endeavour College of Natural Health endeavour.edu.au 63