Antibody production and vaccination Immunity is based on recognition of self and destruction of foreign material. AHL Topic 11.1 IB Biology Miss Werba

TOPIC 11 – ANIMAL PHYSIOLOGY 11.1 ANTIBODY PRODUCTION & VACCINATION 11.2 MOVEMENT 11.3 THE KIDNEY & OSMO-REGULATION 11.4 SEXUAL REPRODUCTION J WERBA – IB BIOLOGY 2

THINGS TO COVER Statement Guidance U.1 U.2 U.3 U.4 U.5 U.6 U.7 U.8 U.9 Every organism has unique molecules on the surface of its cells. U.2 Pathogens can be species-specific although others can cross species barriers. U.3 B lymphocytes are activated by T lymphocytes in mammals. U.4 Activated B cells multiply to form clones of plasma cells and memory cells. U.5 Plasma cells secrete antibodies. U.6 Antibodies aid the destruction of pathogens. U.7 White cells release histamine in response to allergens. U.8 Histamines cause allergic symptoms. U.9 Immunity depends upon the persistence of memory cells. U.10 Vaccines contain antigens that trigger immunity but do not cause the disease. U.11 Fusion of a tumour cell with an antibody-producing plasma cell creates a hybridoma cell. U.12 Monoclonal antibodies are produced by hybridoma cells. J WERBA – IB BIOLOGY 3

THINGS TO COVER Statement Guidance A.1 A.2 A.3 S.1 NOS 4.5 Smallpox was the first infectious disease of humans to have been eradicated by vaccination. A.2 Monoclonal antibodies to HCG are used in pregnancy test kits. A.3 Antigens on the surface of red blood cells stimulate antibody production in a person with a different blood group. S.1 Analysis of epidemiological data related to vaccination programmes. NOS 4.5 Consider ethical implications of research— Jenner tested his vaccine for smallpox on a child. J WERBA – IB BIOLOGY 4

CELL SURFACE MARKERS U.1 Every organism has unique molecules on the surface of its cells. These molecules have a wide range of functions. An MHC marker labels the body’s cells as “self”. An antigen is a molecule that the immune system recognises as “non-self”. J WERBA – IB BIOLOGY 5

REVISION: ABO BLOOD GROUPING TOPIC 3.4 – A.1 ABO blood type is controlled by multiple alleles coding for different antigens on red blood cells J WERBA – IB BIOLOGY 6

ABO BLOOD GROUPING A.3 Antigens on the surface of RBCs stimulate antibody production in a person with a different blood group. These antigens are called agglutinogens. J WERBA – IB BIOLOGY 7

ABO BLOOD GROUPING A.3 Blood type O is the universal donor, as it has no antigens that the recipient’s immune system can react to. Blood type AB is the universal recipient. J WERBA – IB BIOLOGY 8

REVISION 1st line of defence: 2nd line of defence: TOPIC 6.3 1st line of defence: unbroken skin, mucous secretions, body secretions, gut 2nd line of defence: Inflammation  increases blood flow Non-specific cellular response  platelets, leucocytes Fever  kills pathogens; increases activity of IS Protein responses  complement, interferon J WERBA – IB BIOLOGY 9

REVISION 3rd line of defence: Involves the immune response TOPIC 6.3 3rd line of defence: Involves the immune response Antigen presentation Activation of Helper T cells Activation of B cells Production of plasma cells Production of memory cells J WERBA – IB BIOLOGY 10

REVISION TOPIC 6.3 J WERBA – IB BIOLOGY 11

Antigen presentation by macrophage REVISION TOPIC 6.3 Pathogen invades the body. The pathogen’s antigen detected as “non-self” by macrophages. Macrophage tries to ingest the pathogen (phagocytosis) but the ingestion isn’t complete. Macrophage displays the bacterial antigen on its own cell membrane. Macrophage has become an antigen presenting cell (APC). Antigen presentation by macrophage MHC II protein J WERBA – IB BIOLOGY 12

REVISION The APC comes into contact with lymphocytes. TOPIC 6.3 The APC comes into contact with lymphocytes. A Helper T (TH) cell complementary to the antigen on the APC will be identified. Selected TH cell divides by mitosis forming a clone. These processes are known as clonal selection & clonal expansion. Memory T cells are also formed. J WERBA – IB BIOLOGY 13

REVISION Inactive Helper T-cell TOPIC 6.3 Inactive Helper T-cell Macrophage sends a signal to activate the helper T-cell Active Helper T-cell J WERBA – IB BIOLOGY 14

REVISION TOPIC 6.3 J WERBA – IB BIOLOGY 15

B CELL ACTIVATION The TH cells activate complementary B cells U.3 The TH cells activate complementary B cells The B cells also divide to form a clone. Helper T cell presents antigen to B cells Activates complementary B cell B cell divides J WERBA – IB BIOLOGY 16

B CELL ACTIVATION B CELL ACTIVATION: Active Helper T-cell Antibody U.3 B CELL ACTIVATION: Active Helper T-cell Antibody Activated Helper T-cell sends a signal to activate the B-cell Activated Helper T-cell binds to B-cell Inactive B-cell Active B-cell J WERBA – IB BIOLOGY 17

PLASMA CELL ACTIVATION U.3 U.5 U.6 Activated B cells differentiate into plasma cells. Plasma cells make large numbers of antibody proteins. The antibodies are secreted by exocytosis.  aid destruction of pathogen Differentiation of B cell Plasma cell formation Antibody production J WERBA – IB BIOLOGY 18

MEMORY CELL ACTIVATION U.3 U.5 Activated B cells also differentiate into memory B cells. Memory cells remain after immune response. Allow a rapid response if the disease is encountered again (=LONG TERM IMMUNITY) Differentiation of B cell Plasma cell formation Antibody production Memory B cell formation Long term immunity J WERBA – IB BIOLOGY 19

11.1.2 J WERBA – IB BIOLOGY 20

IMMUNE RESPONSE http://highered.mheducation.com/olcweb/cgi/pluginpop.cgi?it=swf::525::530::/sites/dl/free/0072464631/291136/immResponse.swf::immResponse.swf J WERBA – IB BIOLOGY 21

ANTIBODY PRODUCTION U.6 Antibodies (immunoglobulins): proteins produced as a response to the presence of an antigen General structure of an antibody: 2 antigen-binding sites MHC proteins (major histocompatibility complex) T cell receptors do not respond to antigens unless the antigens are associated with MHC proteins J WERBA – IB BIOLOGY 22

ANTIBODY PRODUCTION U.6 The antibodies produced by a plasma cell are complementary to the original antigen presented on the pathogen. They aid the destruction of pathogens. J WERBA – IB BIOLOGY 23

ANTIBODY PRODUCTION U.6 What happens after the antibody has bound to the antigen? Enhances phagocytosis Leads to cell lysis http://kvhs.nbed.nb.ca/gallant/biology/antibody.jpg J WERBA – IB BIOLOGY 24 J WERBA – IB BIOLOGY 24

ANTIBODY PRODUCTION U.6 Neutralisation – attachment of Abs stops toxins from affecting or entering cells, viruses from invading cells, etc Opsonisation – Abs attach to pathogens, marking them for destruction by immune cells – eg. macrophages Agglutination – Abs attach to each other causing the pathogens to clump together, enhancing opsonisation and neutralisation. Complement activation – Abs encourage other components to attack the pathogen and lyse the cell Inflammation – Abs can also cause localised inflammation to help combat the pathogen J WERBA – IB BIOLOGY 25

HISTAMINE Histamine is produced by 2 types of leukocytes (WBCs): Basophils Mast cells Mast cells are found in connective tissues. If they are triggered by an infection, they release histamine into the area. J WERBA – IB BIOLOGY 26

HISTAMINE U.7 U.8 Histamine increases the permeability of the capillaries to WBCs and some proteins (eg. antibodies). This will allow the immune system components to engage the pathogen at the site of infection. J WERBA – IB BIOLOGY 27

HISTAMINE U.7 U.8 Some mast cells can become sensitised by binding of an antibody (IgE). Some environmental chemicals called allergens (eg. pollen) can cause these mast cells to release large quantities of histamine. J WERBA – IB BIOLOGY 28

IMMUNITY U.10 Immunity: having sufficient biological defences against infection Active immunity: immunity due to the production of antibodies by the organism itself after the immune response has been stimulated by a pathogen Passive immunity: immunity due to acquisition of antibodies from another organism in which active immunity has been stimulated J WERBA – IB BIOLOGY 29

IMMUNITY Acquired immunity Naturally acquired Active Passive Infection; contact with pathogen eg. chicken pox immunity Passive Antibodies pass from mother to baby eg. via placenta & colostrum Artificially acquired Vaccine; dead or attenuated pathogens eg. MMR vaccine Injection of antiserum (antibodies) eg. rabies treatment J WERBA – IB BIOLOGY 30

IMMUNITY U.9 U.10 The secondary response to an antigen is much faster and stronger than the first response. Vaccinations deliberately expose someone to a disease so that they develop immunity – without them having to contract the illness itself. Vaccines contain a form of the pathogen or toxin that has been modified (attenuated) so that it is unable to harm the body. Exposure to an attenuated pathogen still allows the production of memory cells against the antigen. J WERBA – IB BIOLOGY 31

IMMUNITY U.9 U.10 J WERBA – IB BIOLOGY 32

SMALLPOX Caused by the variola virus First infectious disease of humans to be eradicated by vaccination in 1980. Achieved worldwide! Last known case was in 1977. Other eradication programs have been less successful, but have reduced numbers. J WERBA – IB BIOLOGY 33

JENNER’S RESEARCH Consider the ethical implications of research NOS 4.5 Consider the ethical implications of research Jenner tested his vaccine for smallpox on a child. J WERBA – IB BIOLOGY 34

JENNER’S RESEARCH A.1 Edward Jenner used cowpox (a virus similar to smallpox) when he was trying to develop the smallpox vaccine In 1796, he deliberately infected an 8y.o. boy with cowpox. Then he deliberately infected the boy with smallpox, but he found that the boy was immune. J WERBA – IB BIOLOGY 35

JENNER’S RESEARCH Ethical issues: No prior research into human testing & side- effects of cowpox No informed consent Child too young to understand dangers and provide informed consent anyway J WERBA – IB BIOLOGY 36

SPECIES-SPECIFIC PATHOGENS U.2 Many pathogens are species-specific: eg. polio, measles, syphillis Others (75%) are zoonotic – meaning that they can be transmitted between humans and other animals: eg. flu, ebola, salmonella J WERBA – IB BIOLOGY 37

MONOCLONAL ANTIBODIES U.11 U.12 Antibodies can be produced in a lab for therapeutic or diagnostic use. Monoclonal antibodies are derived from a single cell. They are pure antibody preparations that are specific for a single antigen. The current technology for making monoclonal antibodies involves fusion of tumour cells and B cells. J WERBA – IB BIOLOGY 38

MONOCLONAL ANTIBODIES U.11 U.12 PRODUCTION: A mammal (eg. mouse) is injected with the antigen. The mouse plasma cells will produce antibodies against the antigen. The mouse plasma cells complementary to the antigen are extracted and fused with tumour cells  forms a hybridoma cell The hybridoma cell divides and produces identical antibodies to the original plasma cell. The antibody can then be harvested. J WERBA – IB BIOLOGY 39

MONOCLONAL ANTIBODIES U.11 U.12 J WERBA – IB BIOLOGY 40

MONOCLONAL ANTIBODIES USES: Pregnancy testing detects the presence of the HCG hormone in the urine HCG is only released during pregnancy Testing for a suspected heart attack Damaged heart muscle cells release a specific cardiac enzyme into the blood ELISA test for HIV Colour change in dimple tray when antibodies are detected Treatment for rabies Diagnosis of malaria J WERBA – IB BIOLOGY 41

MONOCLONAL ANTIBODIES U.11 U.12 http://www.sumanasinc.com/webcontent/animations/content/pregtest.html J WERBA – IB BIOLOGY 42

EPIDEMIOLOGY S.1 Epidemiology: the study of the incidence, distribution and control of diseases Analysing epidemiological data can help guide vaccination programs: Early detection of outbreaks Analysis of transmission Can get more accurate data than the estimates J WERBA – IB BIOLOGY 43

EPIDEMIOLOGY S.1 eg. measles vaccine J WERBA – IB BIOLOGY 44

EPIDEMIOLOGY eg. measles vaccine ◼Africa ◼Eastern Mediterranean ◼South-East Asia ◼Americas ◼Europe ◼Western Pacific J WERBA – IB BIOLOGY 45

ANTIBODY PRODUCTION & VACCINATION Q1. Using the diagram, outline the annual pattern in the data seen across all regions. Identify the regions impacted most greatly by outbreaks. Since 2010, identify the regions in which the incidence of measles is: i. decreasing ii. increasing J WERBA – IB BIOLOGY 46

ANTIBODY PRODUCTION & VACCINATION Q1. Despite having an established vaccination programme in most countries, Europe has seen a peak in measles incidence between 2010 and 2013. Suggest a reason for this (Try researching it!). J WERBA – IB BIOLOGY 47

ANTIBODY PRODUCTION & VACCINATION Q2. What are fused in the production of monoclonal antibodies? Tumour cells and T cells Tumour cells and B cells B cells and T cells Antibodies and antigens J WERBA – IB BIOLOGY 48

ANTIBODY PRODUCTION & VACCINATION Q3. State one use of monoclonal antibodies in diagnosis and one use in treatment. [2] Q4. Outline the principle of immunity. [6] Q5. AHL version - Explain the production of antibodies. [7] J WERBA – IB BIOLOGY 49