BIOLOGY 20 CHAPTER 11 BLOOD AND IMMUNE SYSTEM

BIOLOGY 20 CHAPTER 11 BLOOD AND IMMUNE SYSTEM Nelson Pages 348 – 375

Dividing the cell into its parts (or fractions) is called cell fractionation and is achieved by the process of centrifugation using a centrifuge.

11. 1 COMPONENTS OF BLOOD Average 70 kg person has about 5 L of blood Blood � 55 % fluid or plasma � 45 % blood cells Plasma � 90 % H 2 O � Also: Proteins, glucose, vitamins, minerals, dissolved gases, and waste products of metabolism

TYPES OF PLASMA PROTEINS Types Functions • Albumins • Osmotic balance – maintain H 2 O levels • Globulins • Antibodies, immunity (immunoglobulins) • Fibrinogen • Blood clotting

I. ) ERYTHROCYTES Red blood cells or RBC’s Transport O 2 Packed with hemoglobin �Greatly increases capacity of RBC to carry O 2, by 70 X Heme – iron containing pigment Globin – protein structure �Oxyhemoglobin - gives blood its red color

RBC’s � Are biconcave Greater surface area for gas exchange � Are enucleated (no nucleus) when mature More room for cell to carry hemoglobin � Are made in bone marrow – erythropoieses � Are broken down by spleen and liver Heme is transformed into bile pigments Iron returns to liver for storage and bone marrow for reuse

RBC’s and low O 2 levels � Exercise, high altitude, hemorrhage Lowers O 2 levels in blood kidneys release REF RBC production in bone marrow Anemia � Reduction in blood O 2 due to low levels of hemoglobin or poor RBC production � Causes: hemorrhage, dietary deficiency in iron

II. ) LEUKOCYTES White blood cells or WBC’s Outnumbered by RBC’s Have a nucleus v Types of WBC’s a. ) Granulocytes b) Agranulocytes Why You Are Still Alive - https: //www. youtube. com/watch? v=z. QGOc. OUB i 6 s

c) Phagocytes �Destroy invading microbes by phagocytosis Diapedesis – move like an amoeba • Lysosomes release digestive enzymes � Digests microbe as well as itself • Pus forms – fragments of WBC and invader Phagocytosis http: //faculty. ccbcmd. edu/~gkaiser/biotutori als/eustruct/images/phagocyt. gif http: //highered. mheducation. com/sites/007 2495855/student_view 0/chapter 2/animatio n__phagocytosis. html A colored scanning electron micrograph of a macrophage engulfing a parasite of the Leishmania genus. To defend the body, macrophages will surround a foreign invader, bring it inside the cell, then use enzymes to digest the material.

Types of Phagocytes: a. ) Neutrophils: Neutrophils Toxins, hemorrhage, fever, burns b. ) Eosinophils: Allergies and parasitic worms c. ) Basophils: Damage to tissues http: //www. wisconline. com/objects/index_tj. asp? objid=AP 14704 v Other WBC’s form antibodies which interfere with invading microbes

Neutrophils are very active in phagocyting bacteria and are present in large amount in the pus of wounds. 11

Eosinophils attack parasites and phagocyte antigenantibody complexes. 12

Basophil secrete anticoagulant and vasodilatory substances as histamines and serotonin. Even if they have a phagocytory capability, their main function is secreting substances which mediate the hypersensitivity reaction. 13

The lymphocytes are the main constituents of the immune system which is a defense against the attack of pathogenic microorganisms such as viruses, bacteria, fungi and protista. Lymphocytes yield antibodies and arrange them on their membrane. Two types: B and T lymphocytes 14

Monocytes are the precursors of macrophages. After attaining maturity in the bone marrow, enter the blood circulation. Then they migrate into the connective tissue, where they become macrophages and move within the tissues. In the presence of an inflammation site, monocytes quickly migrate from the blood vessel and start an intense phagocytory activity. 15

III. ) PLATELETS thrombocytes A. k. a Do not contain a nucleus Produced in bone marrow Move through blood vessels and initiate blood clotting reactions

BLOOD CLOTTING Prevent blood loss Process: platelet breaks Ca 2+ and apart thromboplastin becomes and activates thrombin releases prothrombin thrombo -plastin � Microbes cannot enter but WBC’s Platelet strikes a torn blood vessel can splices fibrinogen converted into fibrin wraps around cut and seals it

HARMFUL BLOOD CLOTS Thrombus – blocks a blood vessel � Types: Coronary Cerebral – stroke � If a blood clot moves or dislodges, it becomes an embolus Types of embolisms: Pulmonary, coronary, cerebral Hemophilia v An inherited defect in the clotting process

THE DISCOVERY OF BLOOD TYPES Experiments with blood transfusions, the transfer of blood or blood components into a person's blood stream, have been carried out for hundreds of years. Many patients have died and it was not until 1901, when the Austrian Karl Landsteiner discovered human blood groups, that blood transfusions became safer. Mixing blood from two individuals can lead to blood clumping or agglutination. This can have fatal consequences. Karl Landsteiner discovered that blood clumping was an immunological reaction which occurs when the receiver of a blood transfusion has antibodies against the donor blood cells. Karl Landsteiner's work made it possible to determine blood types and thus paved the way for blood transfusions to be carried out safely. For this discovery he was awarded the Nobel Prize in

IMPORTANT TERMS Antigen Antibody Molecules that cause the Proteins found in blood synthesis of antibodies that attack and neutralize when injected into another substances that are organism foreign to the body

WHAT ARE THE DIFFERENT BLOOD GROUPS? The differences in human blood are due to the presence or absence of certain protein molecules called antigens (agglutinogens) and antibodies (agglutinins). The antigens are located on the surface of the red blood cells and the antibodies are in the blood plasma. Individuals have different types and combinations of these molecules. The blood group you belong to depends on what you have inherited from your parents.

AB 0 BLOOD GROUPING SYSTEM According to the AB 0 blood typing system there are four different kinds of blood types: A, B, AB or 0 Blood group A If you belong to the blood group A, you have A antigens on the surface of your red blood cells and B antibodies in your blood plasma. Blood group B If you belong to the blood group B, you have B antigens on the surface of your red blood cells and A antibodies in your blood plasma.

BLOOD TYPES CONTINUED… Blood group AB If you belong to the blood group AB, you have both A and B antigens on the surface of your red blood cells and no A or B antibodies at all in your blood plasma. Blood group 0 If you belong to the blood group 0, you have neither A or B antigens on the surface of your red blood cells but you have both A and B antibodies in your blood plasma.

ABO BLOOD TYPE SUMMARY:

AGGLUTINATION REACTION

BLOOD GROUP NOTATION According to above blood grouping systems, you can belong to either of following 8 blood groups: A Rh+ (34%) B Rh+ (9%) AB Rh+ (3%) 0 Rh+ (38%) A Rh(6%) B Rh(2%) AB Rh(1%) 0 Rh(7%)

BLOOD TYPING – HOW DO YOU FIND OUT TO WHICH BLOOD GROUP SOMEONE BELONGS? 1. You mix the blood with three different reagents including either of the three different antibodies, A, B or Rh antibodies. 2. Then you take a look at what has happened. In which mixtures has agglutination occurred? The agglutination indicates that the blood has reacted with a certain antibody and therefore is not compatible with blood containing that kind of antibody. If the blood does not agglutinate, it indicates that the blood does not have the antigens binding the special antibody in the reagent. 3. If you know which antigens are in the person's blood, it's easy to figure out which blood group he or she belongs to! Try your luck with the Blood typing game!!! http: //nobelprize. org/medicine/educational/ landsteiner/index. html

BLOOD TRANSFUSIONS – WHO CAN RECEIVE BLOOD FROM WHOM? People with blood group 0 are called "universal donors" and people with blood group AB are called "universal receivers. " Universal Donors! Universal Recipients!

RH FACTOR BLOOD GROUPING SYSTEM Many people also have a so called Rh factor on the red blood cell's surface. This is also an antigen and those who have it are called Rh+. Those who haven't are called Rh-. A person with Rh- blood does not have Rh antibodies naturally in the blood plasma. But a person with Rh- blood can develop Rh antibodies in the blood plasma if he or she receives blood from a person with Rh+ blood, whose Rh antigens can trigger the production of Rh antibodies. A person with Rh+ blood can receive blood from a person with Rh- blood without any problems.

RH BLOOD GROUP First studied in rhesus monkeys Types �Rh positive: Have these antigens present on surface of RBCs �Rh negative: Do not have these antigens present Hemolytic disease of the newborn (HDN) �Mother produces anti-Rh antibodies that cross placenta and cause agglutination and hemolysis of fetal RBCs

ERYTHROBLASTOSIS FETALIS

DIAGNOSTIC BLOOD TESTS Type and crossmatch Blood typing determines the ABO and Rh blood groups of a blood sample. A crossmatch tests for agglutination reactions between donor and recipient blood • Complete blood count……The complete blood count consists of the following: red blood cell count, hemoglobin measurement (grams of hemoglobin per 100 m. L of blood), hematocrit measurement (percent volume of red blood cells), and white blood cell count

DIAGNOSTIC BLOOD TESTS Differential White blood count It determines the percentage of each type of white blood cell Clotting Platelet count and prothrombin time measures • Blood chemistry…. The composition the ability of the blood to clot of materials dissolved or suspended in plasma (e. g. glucose, urea, nitrogen, bilirubin and cholesterol) can be used to assess the functioning and status of the body’s system

11. 2 THE BODY’S LINE OF DEFENSE PAGES 357 - 366 Biology 20 Unit D

11. 2 THE BODY’S LINE OF DEFENCE Pathogen: an organism causing disease �An infectious disease may be caused by: Viruses, bacteria, fungi, protozoa, flatworms and roundworms Staphylococcus aureus can be pathogen in the right conditions on the surface of the skin (causing impetigo and other skin conditions)

Parasites Head Lice (adult stage) Malaria: Singlecelled protozoan parasites of the genus Plasmodium. Four species infect humans by entering the bloodstream. Giardia: a fungi that infects the intestines of animals causing “beaver fever”. People most often get it from drinking contaminated water

TAPEWORMS, RINGWORMS, AND OTHERP ATHOGENS

VIRUSES Influenza Virus (Flu) Human Immunodeficiency Virus (AIDS)

BACTERIA Salmonella typhimurium (Food Poisoning) Syphilis- is an infectious venereal disease caused by the spirochete Treponema pallidum

I. ) FIRST LINE OF DEFENCE: NONSPECIFIC AND EXTERNAL (P 357) Skin – protective � Acidic secretions (p. H of 3 – 5) Respiratory tract (windpipe) – mucus and cilia sweep foreign material away from lung Stomach – acids and protein digesting enzymes destroy microbes Tears, saliva, mucous secretions – lysozyme (enzyme) destroys bacterial cell walls

II. ) SECOND LINE OF DEFENCE – NONSPECIFIC AND INTERNAL (P 357) A. Phagocytes (WBC’s) destroy microbes

TYPES OF PHAGOCYTES

Phagocytosis �Ingestion of invading microbes by certain WBCs

� Pus - remaining fragments of protein, dead WBCs, digested invader

B. INFLAMMATORY RESPONSE Tissue damage due to physical injury Initiates an inflammatory response Nonspecific response that results in swelling, heat, and pain Clues to second line of defence: �Pus �Inflammation

C. FEVER – EXAMPLE OF SYSTEM WIDE RESPONSE TO INFECTION Neutrophils and macrophages digest invaders �Release chemicals Reach hypothalamus Reset body temperature to about 40 OC Fever makes it difficult for harmful bacteria to survive �Fevers 40 OC can be unsafe Enzymes start to denature

D. PROTECTIVE PROTEINS - prevent multiplication of bacteria and viruses i) complement � active against bacteria once activated, some complements form pores in bacterial cell walls and membranes pores allow salts and fluids to enter bacterial cell bacterium expands until it bursts

E. INTERFERON active against viruses tissue cells infected by viruses produce and secrete interferon chemical binds to uninfected cells these cells now produce substances that interfere with viral replication

III. ) THE IMMUNE RESPONSE (THE THIRD LINE OF DEFENCE) slower, but more specific white blood cells and lymph system are involved WBC respond to antigens: any substance recognized as foreign to the body often antigens are part of a bacterial cell wall, viral coat, or foreign cell membrane

CELLS OF THE IMMUNE SYSTEM OVERVIEW:

Immune system detects an antigen T-cells multiply which attack the invader directly called cell-mediated immunity: cells move thru blood and lymph target: bacteria, viruses, etc. that have toxins infected host cells; cancer cells, implanted tissues B-cells multiply which produce antibodies Called antibody mediated immunity: antibodies move thru blood and lymph target: free bacteria, viruses, and in body fluids

1. CELL-MEDIATED IMMUNITY a macrophage engulfs a bacterium, then the bacterial antigen, along with an identification protein, will be displayed on the macrophage membrane appropriate T-cell and its receptor is presented with the antigen, and is now activated T-cell then grows and divides into the following: a) Helper T-cell directly stimulates a B-cell by presenting an antigen to it

b) Killer T-cell release a chemical which forms a pore in foreign cell membrane bearing an antigen; cell swells and bursts c) Suppressor T-cells number increases slowly suppress immune response d) Memory T-cells recognizes original invading antigen; can last a life-time lymphokines: chemicals which stimulate immune cells to divide

2. ANTIBODY-MEDIATED IMMUNITY B-cells produce antibodies: proteins which combine with and inactivate antigens antigen binds to membrane-bound antibody on B-cell divides into: many plasma cells which produce and release antibodies into blood and lymph memory B-cells that remain in bloodstream antibody level increases, and antigens disappear from body

SUMMARY OF 3 RD LINE OF DEFENCE

KILLER T-CELLS (CYTOTOXIC T CELL)DESTROY INFECTED HOST CELLS…KILL THE VIRUS WHERE IT’S MADE!

ANIMATIONS WORTH CHECKING OUT! �http: //bcs. whfreeman. com/thelifewire/content/chp 1 8/1802004. html �http: //highered. mcgrawhill. com/olc/dl/120110/micro 33. swf

Biology 20 Unit D Section 11. 3: Malfunctions of the Immune System – Pages 367 -370 Directions: READ Section 11. 3 In the TEXTBOOK and complete your own notes using the following slides as a guide.

11. 3 MALFUNCTIONS OF THE IMMUNE SYSTEM 1. Can cause two types of problems: Immunodeficiency diseases � Caused by: Virus (HIV) Hereditary condition (severe combined immunodeficiency) SCID Gene mutation Inability to produce T and B cells Exposure to cancer therapy or use of anti – inflammatory drugs 1. Inappropriate attacks of immune system against non – threatening agents l Allergies l Autoimmune disorders

I. ) ALLERGIES Immune system mistakes harmless cells as harmful Symptoms: �Tissue swelling �Mucus secretion �Constricted air passages

Severe allergic reactions may cause anaphylactic reactions �Hives, itching, swelling Cells that “believe” they are in danger release bradykinin Stimulates release of histamine �Produced by basophils (WBCs) and mast cells • Increases permeability of cells of capillaries Causes reddening • PROTEINS AND WBCS LEAVE CAPILLARY IN SEARCH OF MICROBE • Hypertonic, thus, water follows by diffusion

Reactions may be brought on by: �Medications, vaccines, foods Anaphylactic shock can occur quickly �Weakness, sweating, difficulty breathing �Nausea, diarrhoea, drop in blood pressure Treatments or prevention: �Antihistamines �Medical alert bracelet or necklace �Read labels

II. ) AUTOIMMUNE DISORDERS Immune system mistakenly attacks own cells of body �Renegade lymphocytes treat body’s cells as foreign and attack own body’s cells Usually held in check �Mutated T and B cells �Theory: suppressors secrete a substance that tells macrophage to engulf renegade cells

Failure of suppressor T cells to control renegade lymphocytes �Rheumatoid arthritis Against connective tissue of joints �Rheumatic fever Scars heart muscle �Type I diabetes Against insulin – producing cells of pancreas �Lupus Accumulation of antigen – antibody complexes that build up on walls of blood vessels, kidneys, joints, and skin �Multiple sclerosis Against myelin sheath of nerve cells

III. ) ORGAN TRANSPLANT REJECTION Main challenge is immune system’s ability to distinguish “self” from “nonself” Donor organ is identified by distinctive protein markers on its cell membranes �Major histocompatability complex (MHC) Unique to each individual Organ recipient makes antibodies designed to destroy foreign invader

Attempts are made to match MHC of the tissues of donors and recipients as closely as possible �Close relatives �Recently deceased donors To reduce rejection, immunosuppressant drugs are administered �Also reduces immune system’s ability to fight off invading microbes Place patients at risk for infections

ORGAN TRANSPLANTS IN ALBERTA Alberta’s Capital Health Regional Transplant Program �At the U of A Hospital and Stollery Children’s Hospital �HOPE (human organ procurement and exchange) Coordination, recovery, and distribution of organs in Alberta Tissues include: eyes (cornea and sclera), skin, heart valves, and bone

IV. ) STEM CELL RESEARCH Stem cells �Are pluripotent Can give rise to different types of body cells Can replace pancreatic islet cells that have been damaged Can repair damaged cartilage or cardiac tissue �Exist in adult skin stems cells as multipotent stem cells Can be directed to become neurons or muscle cells

Weakening of suppressor T cells: �Drugs or serious infections �Decline with age �Some people are born with defective suppressor T cells Treatment �Immune suppressing drugs Reduce intensity of renegade cells

Autoimmune disease �Immune system mistakenly attacks own cells of body Mutated T and B cells Failure of suppressor T cells

Attempts are made to match MHC of the tissues of donors and recipients as closely as possible �Close relatives �Recently deceased donors To reduce rejection, immunosuppressant drugs are administered �Also reduces immune system’s ability to fight off invading microbes Place patients at risk for infections