1. V.IMMUNITY AND CANCER Genetics of Immunity Human Immune System: evolved to keep potentially harmful organisms out of our bodies Pathogens: disease causing Bacteria: prokaryotic; treated by antibiotics Virus: single or double RNA or DNA wrapped in a protein coat  Reproduce in host cell  Human chromosomes harbor viral DNA (past infections)  Genetic material cannot repair itself (high mutation rate) – No effective vaccine against HIV or the common cold

2. Genetic Control of Immunity: Autoimmune Condition: Immune system attacks an individual’s own tissues ABO Blood Groups: Person’s immune system manufactures antibodies that attack foreign antigens (Type A with antibodies against type B antigens) Rh Factor: Rh + man X Rh - woman with Rh + child (2 nd Rh + child: Bilirubin accumulates brain damage and skin/whites of eyes turn yellow)

4. Human Leukocyte Antigens: WBC with cell surface proteins identify foreign objects Innate Immune Response: Immediate generalized response 1 st line of defense (ear wax, cilia) Inflammation: involves phagocytosis Plasma accumulates; High blood flow Participation of 3 major groups of proteins Complement System: release of histamine (dilates blood vessels) Collectins: protect against bacteria, viruses Cytokines: interferons, interleukins (cause fever)

5. Acquired Immune Response: Humoral Immune Response: releasing of antibodies into the bloodstream  B cells produce antibodies into the bloodstream (B cells are activated by T cells)

6. Cellular Immune Response: cells themselves travel to where they act  T cells stimulate B cells to manufacture antibodies, cytokines, and killer T cells

7. Abnormal Immunity Severe Combined Immune Deficiencies (SCID): Affects both humoral and cellular immunity 50% of SCID cases are X linked Autoimmune Diseases Microchimerism: fetal cells persisting in a female’s circulation Appears to be an autoimmune disease Higher prevalence in women Scleroderma (“hard skin”): swollen joints, fatigue, stiff fingers, masklike face; between 45-60; “body turning to stone”

8. Allergies: Immune System response to a substance (allergen) Asthma: chronic disease  Contractions of airways, inflammation, mucus accumulation block airways  Runny eyes, rashes, anaphylactic shock  Environmental component

9. Altering Immune Function Vaccine: inactive or partial form of a pathogen that stimulates the immune system to alert B cells to produce antibodies Immunotherapy: Hybridomas (artificial cells – B cell fused with a cancer cell) produce monoclonal antibodies (mAbs) target specific antigens Cytokines: boost immunity and destroy cancer cells Transplants: Autograft: transfer tissue from 1 part of a person’s body to another Isograft: transfer of tissue between identical twins Allograft: transfer of tissue between members of the same species

10. Xenograft: a cross species transplant  Hyperacute Rejection Reaction: donor tissue destroyed in minutes as blood vessels blacken and cut off blood supply  Immunosuppressive drugs, stripping antigens from donor tissue, and matching donor to recipient improve success rate of transplants

11. A Genomic View of Immunity Immunity against infectious disease involves interactions of two genomes – ours and the pathogens Crowd Diseases: occur when infectious agents are introduced into a population that has not encountered them before Easily killed Native Americans Arose with the spread of agriculture, trade routes, and urbanization Vanished quickly Bioterrorism: use of pathogens to kill people