Immune ib master2009forupload
- 1. The Immune System Some images courtesy of Steve Taylor…Bandung Intl. School
- 3. PATHOGENS • The immune system responds to the presence of proteins not made by the body. • These proteins are called antigens. • An antigen that causes a disease is called a pathogen. • Pathogen = disease causing organism.
- 4. Pathogen vs. Non Pathogen
- 6. Method of Transmission know a disease for each • Air – “droplets” • Direct contact – physical contact • Through food • Cuts in the skin • Infected needles • Blood transfusion • Animals and Insects
- 7. Types of Pathogens • Bacterial – Cholera, Tetanus • Viral – AIDS, polio, measles • Fungal – Athlete’s Foot, Yeast Infection, • Protozoan - Malaria • Worm – Tapeworm
- 12. Worms • Worms are usually ingested as eggs • Found in minute particles of feces • Eggs hatch into larvae • Can migrate out of the intestines
- 13. Antibiotics • Bacteria vs. Virus – Act against specific chemicals or chemical pathways in prokaryotes. – DO NOT affect Eukaryotic cells. – Viruses are “intracellular” parasites that uses the host cell – Drugs used against them also compromise human cells (chemotherapy)
- 17. Body's First Lines of Defense NONSPECIFIC • Skin – keratin on surface • Mucous membranes – mouth,nose, throat • Tears - lysozyme • Saliva - lysozyme • Stomach Acid - acidic • Urine
- 18. Skin
- 19. Second Line of Defense Counterattack!!!!!...will kill absolutely anything!!! CELLS THAT KILL INVADING MICROBES: Phagocytes: • Recognize chemical receptors on foreign invaders – often proteins • Identifies and destroys pathogens: endocytosis: form vacuole fuse with lysosomes and are digested • Work in the blood – push through capillaries into tissue – Work to control infection – Causes visible inflammation, heat, pus, fever (not over 105)
- 20. Ouch! - ANATOMY OF A SPLINTER!!
- 21. Types of White Blood Cells
- 22. Interferon • Protein • Released by cells infected with viruses • Combines receptors on healthy cells to produce antiviral enzymes. • Inhibit protein synthesis in viruses
- 23. Third Line of Defense: Mounting a Specific Defense!!!! • The type of WBC that make up the “specific” immune system: • Antibodies – specific protein produced by Lymphocyte: » T – Cells » B – Cells Travel in blood and lymph Produced in bone marrow » T – cells mature in the thymus (behind the sternum) » B – cells mature in bone marrow • Antigens – foreign substances that stimulate antibody production
- 25. T and B Cells • T Cells – several types – Activate B cells (t-helper) – Destroys toxins (t-killer) – Stops immune response (t-supressor) • B Cells – – produces specific antibodies for antigens Monoclonal Selection – Production of the same antibody (proliferation) from the original antigen-antibody complex. – Can be referred to as “memory cells’
- 26. Immune System Disorders AIDS – Acquired Immune Deficiency Syndrome • Retrovirus – RNA as its genetic material • RNA is transcribed into DNA • Reverse Transcriptase
- 28. HIV • Human Immunodeficiency Virus • Attacks “Helper” T – Cells. • Process: • T – cells and HIV antigens bind • HIV virus enters and replicates. • T – cell ruptures releasing new viruses • Viruses infect other T – cells • Virus increases & T cells decrease • Without Helper T- cells , lymphocytes cannot form to produce antibodies. • No Antibodies…the pathogen survives
- 29. Animation: How the HIV Infection Cycle Works
- 30. AIDS - transmission • Sexual relations – all forms – Transmitted through small tears in soft tissue • Sharing needles –drug use • Contaminated blood transfusions • Accidents • Tattoos and Piercings
- 33. HIV DATA - THE WORLD • Gapminder: Unveiling the bea
- 34. HIV – Social Implications • The vast majority of cases are in Africa, with rapid increases in Asia and Central America • changes in sexual behavior • unease over blood transfusions • ostracizing • breakdown of family structure – huge loss in work force – drugs are available to control effects of HIV, but cost is high – poor families have limited resources, and are impoverished by the cost of drugs • huge drain on medical resources • poor nations have little drug availability