#1 donohue immune system, vaccines, and antibioticsPresentation Transcript
ImmuneSystem, Vaccines, and Antibiotics Part 2Biology EOC ReviewSC.912.L14.52 By M. Donohue
•What is Immunity???• Brainstorm!• Raise Your Hand!
•Thehomeostasis? Why do System system plays a role in What is Immune you think the immune homeostasis? Your Body Fighting• Disease disrupts stability of an organisms STABLE Against Evil Invaders! INTERNAL environment• Immune systems helps MAINTAIN stability…AKA HOMEOSTASIS• Immune System: • The organ system that protects the body from disease • Made up of specialized cells and organs that work together to protect you from pathogens • Infection- the multiplication of a pathogen in body tissue • Three different lines of defense…we will get to these in a bit…
•How Do We Build Immunity?• You have to make ANTIBODIES!!! Your body marks the • Remember those? attackers, herds them • Definition: protein produced by white together, and blood cells (WBCS) DESTROYS them! • Attaches to antigens of invaders using ”lock and key” mechanism • Antigens are proteins on the surface of call cells and viruses…their id card • Antibodies cause antigens to clump together=easier for your body to attack and destroy • Antibodies in a nutshell Mark invader and herd them together so they can be easily destroyed by other WBCs (white blood cells)• Well how does our body do that? • Two different ways…. • Active Immunity • Passive Immunity
•Two Major Types of Immune Responses• Active Immunity • Passive Immunity • Results from exposure to pathogen • Created by transferring • Can occur naturally… antibodies made by • Pathogen enters one organism into body another organism • immune system • Ex. Rabies makes antibodies…AKA you • Often acquired before get sick birth during fetal • Can occur by development VACCINATION • Weakened or • Newborns receive deactivated virus antibodies through introduced to body their mother’s milk to make antigens • Doesn’t usually make you sick • Next time a person gets infected, their body rapidly makes antibodies to destroy pathogen
•Overview of Vertebrate Defensesagainst pathogens INNATE Immunity ACQUIRED immunity-Rapid responses to a broad range of microbes -Slower responses to specific microbes External Defenses Internal Defenses•Skin •Phagocytic cells •Humoral response•Mucous membranes •Antimicrobial proteins (antibodies)•Secretions •Inflammatory •Cell-mediated response response (cytotoxic •Natural Killer cells lymphocytes)
•The Immune Systems 3 Lines of Defense
•The Immune Systems 3 Lines of Defense • #1: Barriers to Infection (nonspecific) • Function-keep invaders (pathogens) OUT of your body • Skin • Mucous membranes (respiratory tract) • mucus traps pathogens • cilia moves it out of your throat and nose or into stomach (sneeze, cough, swallow) • Mucus, Saliva and tears • contain enzyme lysozyme (enzyme that breaks down cell walls of bacteria) • Perspiring (sweat and oil) • liquid waste secreted from pores that contains acids, salts and enzymes that kill bacteria on surface of skin
•The Immune Systems 3 Lines of Defense• #2 Inflammatory Response (nonspecific)• Function- respond to the invaders that have entered the body and have started to damage precious tissue • White Blood Cells WBCs • Several different types specialized to fight disease• Blood vessels near injury WIDEN(dilate) to let more blood flow to area of injury• Plasma fills spaces between cells• Plasma carries WBCs called MACROPHAGES to injury site • MACROPHAGES- large WBCs that engulf and destroy pathogens and alert other immune cells• Area is swollen b/c of increased blood flow• Fever- increase in temp. makes more less suitable for growth of bacteria and MACROPHAGES work more efficiently
•The Immune Systems 3 Lines of Defense • #3: Immune Response (specific) • Function-specialized attack on SPECIFIC pathogens that have invaded the body • Many WBCs involved • Macrophages, T cells, and B cells • WBCs secrete antibodies, a protein that attaches to specific region of foreign substance called the antigen
•Meet the Troops Who are the warriors saving our bodies? •• Phagocytes • cells specialized in finding and "eating" bacteria, viruses, and dead or injured body cells. • There are three main types 1) the granulocyte 2) the macrophage 3) the dendritic cell• Lymphocytes • migrate to parts of the lymphatic system • T cells and B cells
•Phagocytes • The granulocytes often take the first stand during an infection. • Sacrifice them selves in battle…gobble up invaders until they die (thank you brave warriors…) • The macrophages ("big eaters") • slower to respond to invaders than the granulocyte but they are larger, live longer, and have far greater capacities • ALERT the rest of the immune system of invaders. • The dendritic cells are "eater" cells and devour intruders • Helps ACTIVATE rest of immune system • filter body fluids
•Lymphocytes (specialized attackers)• On the surface of each lymphatic cell are receptors that enable them to recognize foreign substances. • very specialized receptors- each can match only one specific Antigen- • protein on the surface of a cell (good or bad) that signals to other cells what it is• T cells • T cells come in two different types, helper cells and killer cells.• B cells • JOB: search for antigens matching its receptors, connect and become PRATIALLY ACTIVATED • FULL ACTIVATION require proteins from helper T cells • Once FULLY ACTIVATED: • the B cell starts to divide to produce clones of itself called plasma cells and B memory cells.
•T Cells Two types •• Helper T cells main regulators of the immune defense • JOB: activate B cells and killer T cells. • must be activated by antigen presentation • ACTIVATED Helper divides and to produces PROTEINS that activate B and T cells• Killer T cells • specialized in attacking cells of the body infected by viruses and by bacteria (and sometimes cancer cells) • Recognize antigens on invaders and swiftly kill the EVIL invader
•B Cells (2 types)• The plasma cell • Job: Make antibodies that search for other similar invaders • Antibody finds invader, attaches to it and attracts macrophages to come over and gobble up the invader • Some Antibodies also neutralize toxins and incapacitate viruses, preventing them from infecting new cells.• The Memory Cells • Prolonged life span and can thereby "remember" specific intruders (T cells produce even better ones) • The next time the same invader comes into body, B and T memory cells help the immune system to activate much faster • Invaders are wiped out before the infected human feels any symptoms • Immunity against the invader has been achieved
Once the battle is done, the T-suppressor cell calls off the troops so they can rest up for the next battle!
•Nonspecific vs. specific defenses• Nonspecific defenses do not distinguish one infectious microbe from another• Specific defenses recognize and defend against invading microbes and cancer cells • Involves presence of an antigen
•Nonspecific defenses• Skin• Mucus• Macrophages• Inflammatory Response• Interferons and complement proteins • attack microbes either directly or indirectly by impeding their reproduction • Interferons are produced by infected cells • Diffuse to healthy cells where they cause the cell to inhibit viral production • Complement proteins are activated by microbes or immune system • Coat infected cells –easier to eat • Can amplify inflammatory response
•Nonspecific defenses:inflammatory response
•Nonspecific defenses:inflammatory response• Redness, heat, and swelling caused by • Increase in blood flow, fluid, and cells• Inflammatory response disinfects and cleans injured tissues • Pus = dead white cells and fluid• Systemic response is widespread • Toxins or microorganisms released in bloodstream • Circulates through body • Inflammatory weapons • increase white blood cells, • Fever • Low-grade fever can stimulate phagocytosis and inhibit growth of many microorganisms
•Specific immunity• Often more effective than nonspecific response • It also amplifies nonspecific response• Specific response begins due to presence of an antigen • Can either increase # of cells that attack invader directly OR • Produce antibodies• Immune system “remembers” antigens it has previously encountered • Responds immediately and vigorously • Is adaptive
•Antibiotics • What happens when your body can’t fight off infection?• Must call for extra help…Medicine/drugs called ANTIBIOTICS• Drugs used to either kill bacterial or prevent reproduction• Penicillin-1st antibiotic • 1928 • Used to be effective against many bacterial infections • Today, it is the least effective antibiotic against many of the infections it fought• Why???• See next slide….
•Bacterial Resistance to Antibiotics • Why do some antibiotics stop working???• Antibiotic usually kills entire colony of bacteria• Sometimes a few little suckers survive • They develop their own immunity/resistance to the antibiotic (it’s in their simple DNA)…EVOLUTION! • These resistant bacteria reproduce ASEXUALLY and pass off instructions for resistance to offspring • Their little super army of resistant bacterial clones grows quickly over time and occurs every time antibiotic is used• Eventually there may be so many resistant bacteria that the antibiotic won’t work…BIG PROBLEMS!• Need to find a new strategy of attack• SOOOOO…do NOT use antibiotics every time you feel sick…only use when they are prescribed by your Doc!
Explainwhy thisis true…
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•Summary (What you need to know)• Nonspecific vs. specific Immunity • As organisms have become more evolved, SPECIFIC Immunity has developed (helps in survival and reproduction)• Active vs. passive immunity• Antibodies • Protein that attaches to the antigens of invaders and signals to immune cells that it needs to be destroyed• Antigens • Proteins on the surface of cells that indicate to other cells what it is• Macrophages • First ones to Gobble up invaders• T Cells • Attack specific invaders and kill them• B Cells • Produces Antibodies against the invader
Test Your Skills!Fold you paper long ways (hotdog)Title column on the left AnswersTitle the second column Explanations Answers Explanation 1. 2. 3. 4. 5. 6. 7. 8. 9. 10
Test Your Skills!1. What is your body’s first line of defense? a)Skin b)Antibodies c) Red blood cells d)White blood cells
Test Your Skills!2. Scientists from different fieldswork together to continually modifythe chemical composition ofantibiotic medicines. This is to keepup with the adaptive abilities of thepathogens antibiotics are intendedto treat. Antibiotics inhibit theformation of membranes in certainprokaryotes. Which of the followingwould most likely be treated withantibiotics?a. Body cellsb. Foreign pathogensc. Inherited risk factorsd. Cells that carry mutations
Test Your Skills!3. Rather than use a wholevirus, some vaccines use onlyparts of the protein coat of thevirus. Why does this methodwork?a. The viral protein coat is what causes the viral diseaseb. The viral protein coat carries the antibodies needed to fight the diseasec. The viral protein coat carries the antigens that provoke the immune responsed. The viral protein coat provides a food source for viruses that enter the infected host cell
Test Your Skills!4. An antibiotic is advertised asbeing able to kill 95% of all bacteriait is meant to treat. What canhappen with prolonged orrepeated use of this antibiotic?a. That type of bacteria may become extinctb. That type of bacteria may become resistant to the antibioticc. The bodies of the patients may become resistant to the antibiotic.d. A lower does of the antibiotic may be needed to treat the next outbreak of the bacteria
Test Your Skills!5. Which of these statements bestdescribes how a vaccine canprotect a person from an infectiousvirus?a. The vaccine stimulates platelet production, which kills the virus.b. A small dose of the weakened virus is given to the patient so antibodies can form.c. The vaccine stimulates chemical blockers that do not allow the virus to enter the blood stream.d. A small dose of the weakened virus is given to the patient in order to prevent wall synthesis and repair.
Test Your Skills!6. Some forms of vaccination consist ofinjecting a person with inactive viruses.How do the proteins from the inactivevirus protect the person from laterinfections by those viruses?a. They cause a mild infection that prevents the persons body from responding to later infections.b. They bond with receptors on the cells of the person so that later active viruses cannot bind with them.c. They stimulate an immune response that produces memory cells. These cells can produce antibodies when a new active virus infects the cell.d. They remain in the body and serve as a food source for later active viruses instead of feeding on the person’s tissues and causing infection
Test Your Skills!7. Biologically produced proteinscalled antibodies help the body fightinfection in which of these ways?a. Antibodies destroy pathogens by engulfing and digesting themb. Antibodies are found in the antibiotic medications that can be used to help the body fight off infections that have occurred.c. Antibodies identify and destroy foreign material s and pathogens by producing powerful chemicals that dissolve them, making them harmless.d. Antibodies attach to the surface proteins of antigens, inactivating the pathogen or signaling other immune cells to destroy the foreign protein material
Test Your Skills!8. Certain cells are activated bythe immune system to find anddestroy pathogenic cells thatmake their way into the body. Tcells are affected by themacrophages as a step in whattype of the immune systemresponse?a. A specific, general responseb. A specific, targeted responsec. A nonspecific, general responsed. A nonspecific, targeted response
Test Your Skills! 9. The human immune system is made up of special cells, proteins, tissues, and organs that defend against viruses and microorganisms everyday. In the human body there area two different types of response systems (as describe in the table below). Which choice correctly identifies X and Y?? a. X=active , Y= passive b. X= acquired, Y= inborn c. X=inborn , Y= acquired d. X=Antibodies , Y= White blood cells X YEvolutionary Early (vertebrates) Recent (mammals)Types of response General response Targeted, specific antigen responseTiming of response Early line of Slow, development defense, largely becomes stronger in unchanging time, has memoryExamples Natural killer cells, Antibodies made by interferon, body in response to inflammation antigen
10. The p53 gene codes for the p53 protein that locates errors on the DNAfor cellular repair. The diagram below shows the relationship among possibleenvironmental influences, the p53 gene, and cancer.Which of the following statements best describes the relationshipsamong possible environmental influences, the p53 gene, andcancer?a. Environmental influences can lead to mutations in the p53 gene, which can cause certain cancers.b. Increased levels of p53 protein, rather than environmental influences, can cause certain cancers.c. Mutations in the p53 gene increase environmental influences that can cause certain cancers.d. Genes such as p53 are less causal than environmental influences in stimulating certain cancers.
•Answers to #1-101. A2. B3. C4. B5. B6. C7. D8. B9. C10. A