1. Antibody Production and Vaccination
Topic 11.1
Antibody Production and Vaccination

2. Understanding: Every organism has unique molecules on the surface of their cells
ANTIGEN = any foreign molecule that can trigger an immune response
Most common = proteins & large polysaccharides
Found on surface of cells (cancer, parasites, bacteria, pollen, viruses)
Human cells also have proteins & polysacs on surface (MHC proteins)
A healthy immune system can distinguish b/n “self” and “non-self”
ALLERGY = hypersensitivity of immune system
HAY FEVER = allergy caused by pollen or dust

3. Influenza virus cell-surface antigens

4. Application: Antigens on the surface of RBC’s stimulate antibody production in person w/a different blood group.
ABO blood groups: types A, B, AB & O
Rh blood groups: Rh+ and Rh-
Mismatches of blood types cause:
“agglutination” (clumping)
“hemolysis” (RBC’s destroyed)
“coagulation” (clottin; from liquid to gel)

6. A = when mixing Type A with Type A blood = GOOD
A = when mixing Type A with Type A blood = GOOD! B = when mixing Type B with Type A blood = BAD!

7. Review: types of white blood cells

8. Understanding: B lymphocytes are activated by T lymphocytes in mammals

9. Challenge and response
The “challenge” = antigens on surface of pathogens
The “response” = what your immune system does:
Macrophage ingests pathogen
mac displays antigens to helper T cell
Helper T cell binds to antigen and activated
Activated helper T cell binds to B cell & activates it with proteins
B cell divides to produce plasma cells, which secrete specific antibodies
B cell also divides to produce memory cells, for later

10. Antibody production

11. Understanding: Plasma cells secrete antibodies.
Plasma cells = mature B cells that produce & secrete antibodies during immune response
Antibodies = proteins made in response to antigens
Large amount of rER for making and transporting antibodies
Each plasma cell contains the entire DNA of the human individual, but only expresses ONE gene for the ONE protein it makes

12. Understanding: Activated B cells multiply to form a clone of plasma cells & memory cells
Clone = plasma cells that all produce same type of antibody
“Clonal selection” = generation of large numbers of plasma cells that produce ONE specific antibody type
Antibodies stay in body for few weeks or months
Plasma cells persist until infection overcome
Memory cells persist long after infection and inactive
If exposed to same pathogen, memory cell becomes active and responds very rapidly
Immunity = individual has antibodies or memory cells

13. Clonal Selection = generation of large numbers of plasma cells that produce ONE specific antibody type

14. Understanding: Antibodies aid the destruction of pathogens
HOW do antibodies work?
Opsonization: coating antigen with antibody to enhance phagocytosis
Neutralization of viruses & bacteria: prevents adhesion of bac & docking of virus
Neutralization of toxins: bind to toxins, preventing them from affecting cells
Activation of complement proteins: form a pore in pathogen membrane, water and ions enter, pathogen cell lyses
Agglutination: sticking together of pathogens so they can’t enter cells and easier for phagocytes to ingest a bunch at a time

15. How antibodies work!

16. Understanding: Immunity depends upon the persistence of memory cells.

17. Understanding: Vaccines contain antigens that trigger immunity but don’t cause disease
May contain live attenuated (weakened) pathogen or just its antigens
Stimulates primary immune response
If ever exposed to real pathogen, secondary immune response kicks in!
Example: TB (tuberculosis) vaccine
Live attenuated Mycobacterium bovis, a relative of Mycobacterium tuberculosis
Immune system makes antibodies that act on both species, without causing disease
Tuberculosis video

18. Nature of Science: Consider ethical implications of research: Jenner tested his vaccine for smallpox on a child.
Edward Jenner, 18th century scientist – first person to use human being (8 yr old boy) as research subjects in testing a vaccine (smallpox)
Nuremberg Code after WWII protects research subjects
WHO’s International Ethical Guidelines for Biomedical Research Involving Human Subjects (1993)

19. Smallpox

20. Application: Smallpox was the first infectious disease of humans to have been eradicated by vaccination

21. Vaccine scars

22. From BCG (Tb) or Smallpox vaccine

23. Eradication of smallpox
1950 Pan American Health Organization launched effort
1959 World Health Assembly pass resolution for global effort
1967 Smallpox Eradication Unit created
1977 last known case of smallpox (in Somalia)
Reasons for success:
Only transmitted by humans (unlike yellow fever)
Symptoms show up quickly (unlike polio)
Immunity is long-lasting (unlike malaria)

24. Skill: Analysis of epidemiological data related to vaccination programmes.
Epidemiology = study of distribution, patterns & causes of disease in population
Plan & evaluate vaccination programs
1988 WHO, UNICEF & Rotary Foundation combined efforts to eradicate polio
UNICEF launched effort to prevent tetanus through vaccination
Epidemiologists use info about geographic distribution to determine origins of outbreaks & determine effectiveness of vaccination programs
2012 India declared polio-free (until person with polio comes in)
DBQ p 473 #1-6

25. Understanding: Pathogens can be species-specific although others can cross species barriers
Human-specific pathogens: syphilis, polio, measles, HIV
Dog-specific pathogens: canine distemper virus
Cat-specific pathogens: feline immunodeficiency virus (FIV)
Reasons some pathogens affect some species and not others:
Body temp may not reach temp needed to support pathogen
Species may lack receptor on cell for pathogen toxin
Zoonosis = pathogen that can cross species barrier
Examples of zoonotic diseases: bubonic plague, Rocky Mountain spotted fever, Lyme disease, bird flu, West Nile virus
Reasons we see increasing zoonotic diseases: increased contact between animals & humans through livestock & disruption of animal habitats E.g. 1990’s Malaysia, pig farming in habitat of bats infected with Nipah virus: virus moved from bat to pig to man!

26. Thermal scanning camera in airports for possible carriers of bird or swine flu

27. Understanding: White cells release histamine in response to allergens
Mast cells = in connective tissue; secrete histamine in inflammatory response & allergic rxn
Basophils = in blood; wbc’s that release histamine
Histamine = dilates blood vessels and causes them to leak
Histamine released in inflammatory response

28. Understanding: Histamines cause allergic symptoms

29. Allergic reactions Itching Fluid build-up Sneezing Mucus secretion
Inflammation
Rashes
Anaphylaxis = dangerous whole-body allergic rxn (swelling, hives, low BP, dilated blood vessels; usually given epinephrine)

30. Understanding: Fusion of a tumour cell with an antibody-producing plasma cell creates a hybridoma cell

31. Understanding: Monoclonal antibodies are produced by hybridoma cells
Monoclonal antibodies (mAb) = monospecific antibodies made from clones of one single parent cell
For treatment & diagnosis of diseases
E.g. test for malaria, test for HIV, troponin blood test for heart attacks, creation of antibodies for treatment of rabies, pregnancy tests

32. Application: mAb’s to hCG are used in pregnancy test kits
hCG = human chorionic gonadotropin = hormone produced by embryo
If pregnant, urine will contain hCG

33. NOVA’s “Vaccinations: Calling the Shots”