1. Do Now 4/3/15 1.What did Nagler and her team conclude could be a possible cause of food allergies? 2.How were food allergies treated in the experiment conducted by Nagler and her team? 3.Why was administration of Clostridia effective in eliminating symptoms of food allergies? 4.What are the implications of this study on humans?

2. Upcoming Dates Tuesday, 4/7: Blood Quiz Corrections due Thursday, 4/9: Blood, Immune/Lymphatic Quiz Friday, 4/17: Digestive Quiz Thursday, 4/23: Digestive Project due Monday, 4/27: Urinary Quiz; Urinary Project due Friday, 5/1: Urinary & Reproductive Test Thursday, 5/7: Semester 2 Final Exam

3. Allergies Disorder of the immune system When the immune system responds to a “false alarm” When typically harmless substances are encountered by a person who is allergic, the immune system produces antibodies that “attack” the allergen Can result in itching, wheezing, runny nose, watery or itchy eyes, etc. Potential allergens include dust, mold, pollen, some food proteins, etc. Just like with other pathogens, no one is born with these antibodies (no one is born allergic), but after a first exposure, antibodies can develop causing allergic reactions in the future

4. Allergic Reactions Allergic reactions occur when IgE antibodies are produced in response to a harmless antigen, or allergen Exposure to an allergen causes activation of IgE and mast cells Mast cells = specialized cells found in tissues all over the body that store histamine (the chemical that causes symptoms like runny nose or sneezing) Considered to be an “acute hypersensitivity” Almost ½ the populations of North America and Europe have allergies to one or more common environmental allergens Usually not life-threatening but can cause much distress and lost time away from school and work

5. Food Allergies Often caused by proteins that resist heat of cooking, acid in stomach, AND digestive enzymes in the intestines Allergens survive and cross from the intestines into the bloodstream and cause allergic reactions throughout the body Typically has an inherited component (most people with food allergies come from families in which allergies are common)

6. Pet Allergies 15% of Americans are allergic to animals Allergies can develop at any age Caused by pet dander from the skin, not the fur! Even saliva or urine can cause a reaction. Most allergies commonly caused by cats Because they are the worst.

7. For a more detailed look at the physiology of allergies… Read and take notes on page 877 in the textbook Read and take notes on 21.1-2

8. Introduction Immune system Protects the body against Bacteria Viruses Fungi Toxins Parasites Cancer Lymphatic system Works with immune system to remove disease-causing agents Organs Thymus Spleen Lymph nodes

9. The Lymphatic System Network of connecting vessels Collects fluid (lymph) between cells and returns it to bloodstream Picks up lipids from digestive organs and transports them to blood stream Functions to defend the body against pathogens

10. Lymphatic System: Pathways Lymphatic capillaries Extend into interstitial spaces Permeable, thin walls pick up fluid, now lymph Delivers lymph to lymphatic vessels Lymphatic vessels Deliver lymph to lymph nodes Cells in nodes can remove pathogens from lymph and start an immune response Leaves nodes through efferent lymphatic vessels

11. Lymphatic System: Pathways (cont.) Lymphatic trunks Receive lymph from efferent lymphatic vessels Deliver it to ducts Lymphatic collecting ducts Thoracic duct Left side of head and neck, left arm, left side of thorax, entire abdominopelvic area, and both legs Right lymphatic duct Right side of head and neck, right arm, and right side of chest

12. Lymphatic System: Tissue Fluid and Lymph Interstitial fluid Fluid in spaces between cells that has leaked from blood capillaries and has not been picked up by body cells High in nutrients, oxygen, and small proteins Becomes lymph Pushed through lymphatic vessels by squeezing action of neighboring skeletal muscles and breathing movement

13. Back

14. Lymphatic System: Nodes Small, glandular structures Located along paths of larger lymphatic vessels Afferent lymphatic vessels – Lymph to node Efferent lymphatic vessels – Lymph away from node

15. More lymph enters than can leave at one time Cells in nodes Macrophages – digest unwanted pathogens Lymphocytes – start an immune response against pathogen Nodes can generate some lymphocytes Lymphatic System: Nodes (cont.)

16. Apply Your Knowledge What are the lymphatic collecting ducts and what area do they drain? ANSWER: The collecting ducts are: Thoracic duct, which drains the left side of the head and neck, left arm, left side of thorax, entire abdominopelvic area, and both legs; and the right lymphatic duct, which drains the right side of the head and neck, right arm, and right side of the chest.

17. Lymphatic System: The Thymus and Spleen Thymus Soft, bi-lobed organ Located just above the heart in the mediastinum Large in children, shrinks as we age Functions Same as lymph nodes Also produces lymphocytes Produces thymosin – stimulates production of lymphocytes

18. Thymus Gland

19. Spleen Largest lymphatic organ Located in the upper left quadrant of abdominal cavity Functions Filters blood similarly to lymph nodes Removes worn-out red cells If removed (splenectomy), liver takes over most of its function Lymphatic System: The Thymus and Spleen (cont.)

20. Spleen

21. Tonsils Multiple groups of large lymphatic nodules Location – mucous membrane of the oral and pharyngeal cavities Palatine tonsils Posterior-lateral walls of the oropharynx Pharyngeal tonsil Posterior wall of nasopharynx Lingual tonsils Base of tongue

22. Tonsils

23. Defenses Against Disease (cont.) Two major types of lymphocytes B Cells and T Cells Recognize antigens in the body T Cells  Cell-mediated response  Bind to antigens on cells and attack them directly  Secrete lymphokines that increase T cell production and directly kill cells with antigens T Cells  Cell-mediated response  Bind to antigens on cells and attack them directly  Secrete lymphokines that increase T cell production and directly kill cells with antigens B cells  Respond to antigens by becoming plasma cells  Plasma cells make antibodies  Memory B cells produce stronger response with next exposure to antigen B cells  Respond to antigens by becoming plasma cells  Plasma cells make antibodies  Memory B cells produce stronger response with next exposure to antigen Response

24. Back

25. Defenses Against Disease (cont.) T cell activation Begins when macrophage ingests and digests pathogen with antigen on it Antigens are placed on cell membrane of macrophage T cell recognizes and binds to antigen and the major histocompatibility complex (MHC) on the surface of the macrophage Now can divide to form other types of T cells

26. Defenses Against Disease (cont.) Types Cytotoxic T cells Protect body against viruses and cancer cells Helper T cells Increase antibody formation, memory cell formation, B cell formation, and phagocytosis Memory T cells Remember the pathogen that activated original T cell Later exposures trigger an immune response more effective than initial response

27. Defenses Against Disease (cont.) Natural killer (NK) cells Type of lymphocyte Primarily target cancer cells Kill on contact Do not recognize a specific antigen

28. Apply Your Knowledge Identify whether each item refers to T cells, B cells, or NK cells: ___ Primarily target cancer cells ___ Respond to antigens by becoming plasma cells ___ Must be activated to respond to an antigen ___ Bind to antigens on cells and attack them directly ___ Kill on contact ___ Need macrophages and MHC for activation ___ Make antibodies against specific antigen B NK T T T B ANSWER:

29. Major Immune System Disorders Cancer Uncontrolled growth of abnormal cells form malignant tumors 200 known types Treatment based on stage 0 – very early; cancer cells localized I – spread to deeper layers or some in surrounding tissues II – spread to surrounding tissues but contained in primary site III – spread beyond primary site into nearby areas IV – spread to other organs Recurrent – reappeared after treatment

30. Common Immune System Disorders Autoimmune disease Body attacks its own antigens Examples Psoriasis Rheumatoid arthritis Graves’ disease Myasthenia gravis Multiple sclerosis Type I diabetes (mellitus)

31. HIV Read article about potential ‘cure’ for HIV http://www.cnn.com/2014/03/06/health/hiv-baby- cured/ http://www.cnn.com/2014/03/06/health/hiv-baby- cured/ Research and write a summary of the mechanism of HIV and how antiretroviral treatment is used to combat it