The Bodys Defenses The Immune System The Immune

The Body’s Defenses: The Immune System

The Immune System o Factors n n n that cause Disease Inheritance – Genetic Traits Microorganisms – bacteria, virus, fungi, protozoa Pollutants chemical agents in environment. Ex. coal dust, asbestos, lead, mercury, PCB’s Organ Malfunction - ex. Diabetes Harmful Lifestyle - Ex. Tobacco, alcohol, drugs, unsafe sex.

The Immune System o Pathogen – a disease-causing agent.

The Immune System o Normal Flora – not all organisms are pathogenic o o o Ex. Digestive Tract Ex. URT- upper respiratory tract Ex. Skin

The Immune System o Communicable Disease - diseases that you can "catch" from someone or something else. Some people may use the words contagious or infectious when talking about communicable diseases. http: //www. whfreeman. com/kuby/con_index. htm? 99 anm

The Immune System o Timeline of Beliefs n n n Evil sprits, a form of punishment Hippocrates “Father of Medicine” 1600’s Van Leeuwenhoek 1762 Germ Theory Koch – 1870’s Postulates for identify causative agent 1932 Electron microscope

Vectors of Infection o Direct Contact Ex. Polio, STD o Droplet infection Ex. Mucous, saliva o Food borne Ex. Food infected streptococcus Food poisoning salmonella o Water Borne Ex. dysentery, typhoid fever o o Air Borne Objects (water + soil can serve as reservoirs for pathogen)

Vectors of Infection o Puncture Ex. Tetanus, rabies o Carriers - people carry the illness to other people serves as reservoirs Ex. “Typhoid Mary” o Insects Ex. Mosquito Malaria http: //highered. mcgraw-hill. com/sites/0072437316/student_view 0/chapter 28/animations. html#

The Immune System FIRST LINE - NONSPECFIC DEFENSES PROTECT AGAINST INFECTION o Skin - Keeps pathogens out. o Lysozymes - enzymes in sweat and tears that kill pathogens (destroys bacterial cell walls causing lysis). o Chemicals/ acids - acidic areas near bodily opens are unfavorable to pathogens.

The Immune System FIRST LINE - NONSPECFIC DEFENSES PROTECT AGAINST INFECTION Mucous membrane – layer of epithelia tissue covering internal surfaces of the body that secretes mucous and functions as a nonspecific defense. Nose hairs in nasal cavity catch pathogens. CILIA MUCOUS MEMBRANES

The Immune System SECOND LINE - NONSPECFIC DEFENSES PROTECT AGAINST INFECTION o Inflammatory Response – series of events, initiated by an injury or local infection that suppress infection and promotes healing. n Damaged cells release histamine, which causes blood vessels to dilate. This allows for blood and Immune system cells to move more quickly to the sight of injury. http: //www. whfreeman. com/kuby/con_index. htm? 99 anm

The Immune System SECOND LINE - NONSPECFIC DEFENSES PROTECT AGAINST INFECTION o Histamine – chemical released by injured cells in an inflammatory response.

The Immune System SECOND LINE - NONSPECFIC DEFENSES PROTECT AGAINST INFECTION o Complement system – defensive proteins that circulate in the bloodstream. n n n Complement proteins surround a pathogen. The proteins punch holes into the cell membrane of the pathogen causing it to burst, which results in death (apoptosis). The left over debris will be engulfed by a macrophage.

The Complement System SECOND LINE - NONSPECFIC DEFENSES PROTECT AGAINST INFECTION http: //www. whfreeman. com/kuby/con_index. htm? 99 anm

The Immune System o Interferon – protein released by cells that inhibits viruses from replicating.

q. RBC’s Transport O 2 q. WBC’s serve a role in the immune system they come from bone marrow, the spleen or other lymphatic tissues in the body.

The Immune System o Neutrophil – white blood cell that engulfs pathogens and kills itself through the release of chemicals. o Macrophages - large white blood cell that engulfs pathogens. o Natural Killer Cells – immune system cell that attacks other cells that are infected with pathogens.

The Immune System o Cytotoxic T Cells – white blood cell that attacks and kills infected cells. o B Cells – white blood cell that labels pathogens for destruction by macrophages. o Helper T Cells – white blood cell that activates cytotoxic T-Cells and B-Cells in an immune response.

The Immune System THIRD LINE OF DEFENSES IS SPECFIC o Antigen - a substance triggers immune response. o Antibody – defensive protein released by plasma cells during an immune response.

The Immune System o Plasma Cells – cell that releases antibodies in response to a specific antigen. o Memory Cell - protects against defeated pathogen.

The Immune System Helper T- Cell binds to the surface of other cells to display antigen and this will start a Cell- mediated immune response. http: //highered. mcgraw-hill. com/sites/0072437316/student_view 0/chapter 48/animations. html#

The Immune System Antibodies dissolved in the blood bind to antigens to trigger an Antibody mediated immune response. http: //highered. mcgraw-hill. com/sites/0072437316/student_view 0/chapter 48/animations. html #

DISEASES ARE TRANSMITTED IN VARIOUS WAYS German Physician Robert Koch (1843 -1910) Determined that pathogenic bacteria caused anthrax. From his experiences Koch was able to develop a systematic procedure to identify other pathogens.

The Immune System Edward Jenner noticed that milkmaids that got cowpox were immune to more serious small pox. Jenner deliberately infected people* with cowpox they were later immune to small pox. This is the basis of vaccination. * Jenner’s son was first test patient. Way to go father of the year! Vaccination – the application of a vaccine to produce immunity. Immunity - resistance to a disease.

The Immune System Vaccines were traditionally – prepared from killed or weakened (attenuated) pathogens and introduced into the body to produce immunity. http: //pathmicro. med. sc. edu/flash/hiv 2000. html

The Immune System o Vaccinations are injections that contain: 1. dead form of pathogen 2. weakened form of pathogen 3. weakened form of toxin (damaging chemical) ex. Polio, rubella, diptheria o Body keeps some of the white blood cells used to attack the microbes. Such as: memory B cells http: //www. whfreeman. com/kuby/con_index. htm? 99 anm

The Immune System Types of immunity: (a) Getting sick making own antibodies (b) Receive antigen to make own antibodies (c) Antibodies made by mother are transferred to infant (d) Use antibodies made by an animal and inject into a human http: //highered. mcgraw-hill. com/sites/0072437316/student_view 0/chapter 48/animations. html#

The Immune System o Exposed to same pathogen twice. The first time you get sick. The immunes system makes antibodies for future infections. In the case that you are infected with the same pathogen again your immune system will be able to respond quickly enough the second time so you do not get sick again. Ex. Chicken Pox.

The Immune System o Antibiotics - discovered by Fleming in 1929 when he contaminated his culture with mold. Alexander Fleming with a colony of penicillin. Artifacts from the early phase of penicillin development include handwritten notes by Alexander Fleming, a mold colony, and an ampule.

The Immune System How antibiotics are effective: Harmful effects: Prevents bacteria from making enzymes can’t build cell walls or maintain them Inhibits protein synthesis no repair or growth Kills helpful bacteria Inhibits the formation of cell membrane Allergic reaction Resistance (NOT “IMMUNITY”)

The Immune System THE IMMUNE SYSTEM SOMETIMES ATTACKS THE BODY TISSUES Autoimmune disease – a disease in which the immune system cannot distinguish body cells from pathogens. Rheumatoid arthritis The immune system destroys cartilage at the end of bones. Without cartilage bones rub together causing arthritis.

The Immune System o In an organ transplant one’s immune system sees the new organ as foreign substance, possibly pathogenic and it tries to destroy it. o This is referred to as organ rejection. Drugs are given to suppress the immune system so this doesn’t happen.

The Immune System HIV INFECTION LEADS TO IMMUNE SYSTEM COLLAPSE o AIDS – (Acquired Immunodeficiency Syndrome) disease caused by infection by HIV that results in a depressed immune system. o HIV – human immunodeficiency virus that causes AIDS. o CD 4 – a receptor protein on human cells that is targeted by HIV. http: //www. whfreeman. com/kuby/content/anm/kb 03 an 01. htm

http: //highered. mcgraw-hill. com/olc/dl/120088/micro 41. swf http: //pathmicro. med. sc. edu/flash/hiv 2000. html

The Immune System HIV INFECTION LEADS TO IMMUNE SYSTEM COLLAPSE o HIV targets and destroys Helper T- Cells. The role of the Helper T-Cell is to relay messages other immune cells. o Helper T-cell acts as the “middle man” if destroyed the immune system breaks down making a person susceptible to other pathogens. http: //www. whfreeman. com/kuby/con_index. htm? 99 anm

The Immune System HIV INFECTION LEADS TO IMMUNE SYSTEM COLLAPSE o Testing for HIV - look for antibodies - count helper T-cells - less 200 T-cells/ml AIDS ELISA test http: //www. biology. arizona. edu/immunology/activities/elisa/technique. html?

The Immune System HIV INFECTION LEADS TO IMMUNE SYSTEM COLLAPSE o Transmission- RNA hides inside virus/ infected wbc’s 1. sexual contact 2. needles 3. infant to mother NOT FROM: Mosquitoes, saliva, urine, tears

The Immune System SOMETIMES ANTIGENS CAN CAUSE ALLERGIC REACTIONS Allergies - a reaction (overreaction) by the body’s immune system to a harmless antigen. The harmless antigen triggers the releases of histamines Ex. pollen http: //highered. mcgraw-hill. com/sites/0072437316/student_view 0/chapter 48/animations. html# Allergic Reaction

The Immune System o ENDEMIC Disease constantly present in area o EPIDEMIC An outbreak of a contagious disease that spreads rapidly and widely. o PANDEMIC A world wide epidemic.

Public Health Measures 1. Safe Water 2. Sewage Management 3. Food Safety 4. Animal Control Programs 5. Vaccination Programs