The Body’s Defenses

1. The Body’s Defenses By: Ah Young Byun and Kaja Kasperova

2. Vocabulary • AIDS: (acquired immunodeficiency syndrome) a virus that attacks the immune system. • B Cells: a lymphocyte that produces chemicals and destroys different kind of pathogen. • T Cells: a lymphocyte that recognize one pathogen from another. • Lymphocytes: a white cell that destroys a specific target at the pathogen. • Antigens: a cell of the immunity system that can recognize a molecule inside the body or outside.

3. Introduction • Our immune system must be very sensitive in detecting the features of other cells. • Our immunity system must distinguish intruders from our own cells. • Also our defense network is as aggressive as it must be sensitive. • Their task it to destroy foreign intruders such as: bacteria, viruses, fungi, toxic chemicals, or cancer cells.

4. Introduction • The nervous system is the most complex biological system we have. • The nervous system consists of master glands, but main thymus. • The nervous system carries a lot of cells like: 1.Cells that prompt 2. Cells that alert, 3. Cells that facilitate, 4. Cells that activate, 5. Cells that surround, 6. Cells that kill, 7. Cells that clean up.

5. Basic Functions of the Immune System • The organs • Cells • Cell products • Messenger molecules This is the network to protect us from diseases, or heal wounds which we got by injury or invasion.

6. General Defenses • For the barriers, the pathogens gets into your body sometimes and damages your cells. • When cells are damaged they release this chemical called inflammatory response. • Inflammatory response: fluid and certain types of white cells leak from blood cells and go into nearby tissues, than the white cells fight the pathogen. • The inflammatory response is sometimes called the body’s general defense. • Phagocytes: are white cells that destroy the pathogen.

7. Immune response: is the pathogen is infected it can cause a fever, which is also called the third line defense. The immune system can distinguish the difference of pathogens. It reacts to the pathogens with different defenses. Lymphocytes: are the T Cells, and B cells, are the defenses against the pathogens. T Cell: identify the pathogens and distinguish one kind of pathogen from another. Antigens: are molecules on cells that recognize if they are part of your body or not. B Cells: produce chemicals that destroy every kind of pathogen. Antibodies: the chemicals the B cells produce. The Immune System

8. T Cells • The T Cell is usually divided into two major subsets that are functionally and phenotypically different. • The T helper subset is called the CD4 + T Cell, which is a the most important coordinator of the immune regulation. • The main function of the T cell is to fight of active factors that activate other white blood cells to fight off infections. • The other main type of T Cell is called the T Killer or CD8+ T Cell. • Which fights of directly certain tumor cells, or viral- infected cells and sometimes parasites.

9. B Cell • B cells circulate around the body with antibody molecules on their surface. • When the B cells get a signal of an antigen, they transfer into a plasma cell. • Their only goal with turning into an plasma cell is to shake out an antibodies that hook on to the antigens. • Some B cells also remember their fight with foreign intruders. • Antibodies are produced only if an same invader attacks again. • Vaccines carry some of antigens, which follows for an attack. http://www.youtube.com/watch?v=JnlULOjUhSQ

10. Cells That Kill • Natural Killer Cell – is similar to the CD8+ T Cell but it kills melanomas, lymphomas, viral- infected cells, and most herpes. • Granulocytes or Polymorphonuclear (PMN) Leukocytes - this cells contain of three cells (neutrophils, eosinophils, and basophils) they usually rid of parasites, and bacteria from your body. • Macrophages – pick up and ingest foreign materials than present this as antigens to other cells of the immune system (T Cells and B Cells). • This is one of the most important steps in the immune response. • Dendritic Cells – they are found all over the body and they are more important than the macrophages. • The problem is that we don’t know so much about the dendritic cells since they are so hard to find.

11. Antigens • People call antigens the fingerprints of the immunity system. • Cells that are a part of our bodies send the “self” message, and the cells that are not send the “foreign” message. • Since the antigens attacks right away a foreign intruder, it is always hard to do a organ transplant. • So when there is a organ transplant the doctors give the patient a drug to prevent the rejection of the new organ. • When the immune system overreacts to an outside antigen, that’s when you get an allergy. • Hayfever is an example of a hyper response to grass, pollen, or ragweed.

12. Antigens • When the immune system doesn’t react the way it is suppose to, the result is autoimmune disorder. • Lupus erythematosus, and rheumatoid arthritis are examples of autoimmune disease. • When our immune system fails at reacting properly to an outside virus, than a infection happens. • From that if the immune system fails at identify and destroying whatever is inside your body, the cells turn malignant (which means cancer development). • When a cell turns malignant, its surface also changes.

13. Antibodies • Antibodies are the bodies complement to antigens. • Antibodies are like marvels that can fit into million keyholes of different antigens. • Each antibodies has a unique molecular configuration, which can fit into any antigen. • Antibodies are carried around by the white blood cells called lymphocytes (T Cell and B Cell). • It is the B Cell that displays and secretes the antibodies.

14. AIDS (Acquired immunodeficiency Syndrome) • -disease caused by a virus attacking immune system • -one of the leading causes of death (usually 25 to 44) • -HIV(Human immunodeficiency virus) causes the AIDS

15. HIV • HIV spreading • used to reproduce only inside the cell • it reproduces only inside cells (like T cells) • it also can spread one person to another which means infected person to uninfected person • sexual contact is one way to spread worst thing is when a woman has her baby inside the baby can get infected • HIV affects the body • more than 30 million might be infected with HIV • the body loses its ability to fight disease(when the viruses destroy T cells)

16. Inflammatory response • -'inflammatory' comes from a Latin word meaning "to set on fire“ • -the second line of defense-comtains fluid and certain types of white blood cells • -it leaks from blood vessels into nearby tissue. • -then the white blood cells fight the pathogens • -it sometimes called the body's general defense because it's same as the pathogen • -the kinds involved in the inflammatory response are called phagocytes

17. Phagocyte • -white blood cell that engulfs pathogens • -it destroys them by breaking them downsometimes the chemical produces when the inflammatory causes a feverit makes you feel bad, but it might be helping your body fight the infection

18. How it works • -the blood vessel widen in the area affected by pathogens • -this increases the area that the blood flows • -the blood that leaked out from them make the affected area red and swollen • -it feels slightly warm than normal if you touch this area

19. The End  Thank you for watching, and listening 