1. Notes: The Immune System What the Immune System Does The immune system is the body's defense against infectious organisms and other invaders. Through a series of steps called the immune response, the immune system attacks organisms and substances that invade our systems and cause disease. The immune system is made up of a network of cells, tissues, and organs that work together to protect the body.

2. Frostbite!

3. The Black Death: Bubonic Plague

4. Tree man: Viral infection

5. Tree Man

6. 1 st Line of Nonspecific Defense First line is nonspecific defense. Helps prevent pathogens (disease-causing “things”) from entering the body. These include: 1. Skin it blocks against pathogens & it’s acidic with a pH of 3-5 2. Mucous membranes that release mucus and trap microbes. 3. Cilia in the respiratory system that sweep out mucus with its trapped microbes. 4. Stomach acid that kills germs that enter through the nose & mouth

7. MRSA Methicillin-Resistant Staphylococcus aureus

8. 3D Medical Animation: Antibody Immune Response

9. Acinetobacter baumannii (gram-negative bacterium)

10. Skin Grafting

11. Skin Graft: Day 35

12. Respiratory and Digestive System

13. Q: What happens when a pathogen breaks through the 1 st line of defense? Answer: 2 nd line of nonspecific defense! There are 4 important nonspecific defenses that take action. 1.Inflammatory response & Temperature response (Above 108 F, people die!) 2.Leukocytes: White blood cells (WBC, macrophages) which attack & kill the pathogens. White blood cells have a nucleus.

14. When the 1 st line of defense fails

16. White Blood Cells (WBC) Neutrophils: it engulfs & destroys pathogens, very abundant. Macrophages: ingest & kill pathogens they encounter & also clear dead cells from the body. Natural Killer Cell: Large WBC that puncture the cell membrane & H2O rushes into the cell. They also attack cancer cells too.

17. The Body’s Defense Mechanism!

18. Make sure you understand this… 1. The first and second lines of defense of the human body are nonspecific immune responses... 2. The third line of defense in your Immune System, reacts in specialized ways for various invaders.

19. David Vetter (1971 –1984) ● Born with severe combined immunodeficiency (SCID)

20. 1. SCID is an X-linked disorder, and David's mother was a carrier. 2. Ten seconds after birth, David was placed in a plastic bubble 3. David needed a germfree environment, so he had to be inside his bubble for 12 years.

21. Doctors hoped to cure David’s SCID using a bone marrow transplant...

22. The Bone Marrow Transplant ● October 21, 1983, David received a bone marrow transplant from his sister Katherine. ● The marrow contained the Epstein-Barr virus, that causes mononucleosis. ● While knowing that David would have to live life in a bubble, doctors encouraged his mother to go through with the pregnancy. Some people have said that in this situation, it would have been better to terminate the pregnancy. ● What do you think?

23. Bone Marrow: What’s inside?

24. Q: What happens when the pathogen gets past the 2 nd line of defense? Answer: The 3 rd Line of Defense is set off, which are T-cells and B-cells. these are specialized white blood cells. They produce antibodies (the good guys) and are specific to different antigens (the bad stuff like pathogens)

25. Specific or Acquired Immunity - The Third Line of Defense The 3 rd -line of immune defense is a ‘smart system’ that can learn and change. Specific immunity involves cells and cell products that can recognize and remember specific pathogens. This is why you become ill with some infectious diseases one time only, and never again. This is because, after initial exposure, your body has a police squadron of cells specifically trained to find and destroy that particular pathogen. Our specific immunity is also why we can use vaccinations to prevent illness.

26. Third Line of Defense is Specific! There are two different parts, or branches to this response. They consist of: 1.Cell-mediated immunity T-lymphocytes, Natural Killer cells 2. Humoral immunity (antibody) - B lymphocytes

27. The Lymphatic System It is a network of tubes that drains the fluid around the body’s cells back into the bloodstream. When you have a cold/flu or any infection, the lymph nodes in your neck or groin, under your arm, may swell as the lymphocytes fight germs (WBC’s have swallowed up the germs!)

28. The Lymphatic System! One & 2 liters of lymph fluid is circulating in the lymphatics (lymph vessels) & body tissues. There is NO pump for this system, it “circulates” as a side effect of the heartbeat and muscle movements!

29. Flesh-Eating Bacteria!

30. Gangrene: The Immune System is working very hard to win this infectious battle!

31. * Your eyes are protected by tears that wash away germs. Tears contain an enzyme called lysozomes that kills bacteia. * If you get the flu, it is your T lymphocytes that help you heal! * When you exercise hard, your body burns up energy 20 times faster!

32. What purpose does your mucus have in the body? Mucus-producing tissue lines the mouth, nose, sinuses, throat, lungs, and gastrointestinal tract. Mucus acts as a protective blanket over these surfaces, preventing the tissue underneath from drying out. It’s like the oil in an engine.

33. Coughing up clear mucus = mild infection or allergies. Yellow mucus = bacterial infection in the lungs or bronchi Green mucus = fighting the infection, filled with pus & white blood cells (good indication) Note: could be an indication of cystic fibrosis disease and should be discussed with your doctor. Blood in mucus =indicates hemorrhage or bleeding in the lungs and could signal a very dangerous health condition like pneumonia or tuberculosis. Brown mucus = smoking

34. What are antibiotics? The word antibiotic comes from the Greek anti meaning 'against' and bios meaning 'life' (a bacterium is a life form).' Antibiotics are also known as antibacterials, and they are drugs used to treat infections caused by bacteria. Bacteria are tiny organisms that can sometimes cause illness to humans and animals. The singular word for bacteria is bacterium.

35. Antibiotics & Viruses Antibiotics do not work on viruses because viruses are not alive. A bacterium is a living, reproducing lifeform. A virus is just a piece of DNA (or RNA). A virus injects its DNA into a living cell and has that cell reproduce more of the viral DNA. With a virus there is nothing to "kill," so antibiotics don't work on it.

36. Children of Chernobyl (Gamma Radiation Poisoning)