Instructor s Guide. Films for the. Humanities & Sciences i A Wealth of Information. A World of Ideas. The Human Body: How It Works THE IMMUNE SYSTEM

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1 i A Wealth of Information. A World of Ideas. Instructor s Guide The Human Body: How It Works Introduction This program is part of the nine-part series The Human Body: How It Works. The series uses physiologic animations and illustrations, microscopic imaging, expert commentary, and footage of the body in motion to provide a thorough overview of the amazing human machine. The series includes: Cells, Tissues, and Skin The Immune System Human Development and the Reproductive System The Respiratory System The Circulatory System The Skeletal and Muscular Systems Digestion and Nutrition The Endocrine System The Nervous System and the Senses Topics Chapter 1: Innate Immunity and Defenses The program begins with an overview of innate immunity. Skin, saliva, tears, and mucus membranes are identified as passive, barrier defenses. Viewers then learn that if an antigen breaches these, the inflammatory response kicks in as part of the non-specific, reactive response and that inflammatory mediators, phagocytosis, and the complement system will act together to destroy the invaders. Chapter 2: The Cells, Tissues, and Organs of the Immune System This section begins by noting the evolution of stem cells into leukocytes, which then evolve into phagocytes and lymphoid cells. It describes the subsequent development of these two cell families into monocytes, Copyright

2 B-cells, and T-cells. The tissues and organs of the lymphatic system are defined, along with a brief description of the part they play in fighting infection. Also covered: The appendix; SALT and MALT. Chapter 3: The Humoral Immune Response B-cells, and the five basic types of immunoglobulins, are the focus of this chapter. Vivid animations clarify the interrelated actions of macrophages, interleukins, T-cells, and B-cells in response to invading antigens. Also covered: Antigen-presenting sites; B-cell amplification; memory B cells. Chapter 4: Cell-Mediated Immunity The three different kinds of T-cells are highlighted in this chapter as key components of cell-mediated immunity. Viewers see exactly how T-cells, B-cells, and cytokines coordinate with the involvement of the major histocompatibility complex to destroy harmful organisms. Also covered: How the MHC functions to distinguish between good cells and bad cells; how HIV attacks Helper T-cells, leaving the immune system compromised. Chapter 5: The Importance of Vaccines The difference between active and passive types of natural and artificial immunity is the main topic here. This section also addresses the benefits and limitations of vaccines, and why it has been so difficult to develop an AIDS vaccine. Chapter 6: Allergies and Autoimmune Diseases In this section viewers learn how an over-reactive immune response leads to autoimmune diseases. Type 1 diabetes, rheumatoid arthritis, and pollen allergies are explained in terms of what happens when B-cells produce too many antibodies. Also covered: Mast cells; anaphylactic reaction. Chapter 7: Immunity as a Tool for Scientists The program ends with a discussion of immunology s growing significance as scientists work to develop new vaccines and why stem cells hold such promise. Learning Objectives Students will learn The parts and functions of the immune system The details of passive, barrier defenses, and of non-specific, reactive defenses (including phagocytosis and the complement system), and how they protect us How macrophages, leukocytes, and lymphoctyes fight infection How the tissues and organs of the lymphatic system fight infection Copyright

3 The function of B-cells, antibodies, and other key components of the humoral immune response The role of MHC and different kinds of T-cells in cell-mediated immunity The differences between active and passive types of natural and artificial immunity How vaccines and serums work The cause of allergies and other common autoimmune diseases Why stem cells are unique Vocabulary acquired immunity: When the body develops a defense to a specific antigen. active, artificial immunity: A way to acquire immunity to a particular disease by being vaccinated against it. It differs from passive, artificial immunity in that it stimulates the body to make its own T- and B-cells, thus providing long-lasting immunity. active, natural immunity: A way to acquire immunity to a particular disease by being exposed to it. antibodies: Immunoglobulins. antigen: A substance that the immune system recognizes as foreign and reacts against. Technically, an antigen is a molecule found on the surface of viruses and bacteria, but sometimes the word is used loosely to refer to any foreign substance invading the body, or to the entire virus or bacteria. antigen-presenting site: The part of a macrophage s surface on which are displayed pieces of an antigen it has engulfed and broken down. Helper T-cells bind to antigen-presenting sites and then send out messages to attract B-cells. B-cell: A key part of the humoral immune response, it is a type of cell produced in the bone marrow that eventually develops into a B-lymphocyte, which is the white cell responsible for producing antibodies. B-cell amplification: A process by which B-cells replicate in order to produce more antibodies. Some of the replicated B-cells become memory cells. B-lymphocyte: A lymphocyte developed from a B-cell, but sometimes also called a B-cell, that creates antibodies. Copyright

4 bone marrow: A tissue that fills most bone cavities, this is where red blood cells and white blood cells are created. cell-mediated immunity: A part of the specific immune response in which T-cells, along with the MHC, play the key role by causing infected cells to burst open. complement protein: A substance produced by macrophages to help fight off antigens. complement system: Part of the innate immune system, it is a non-specific, reactive process in which proteins kill pathogens. In a classical complement pathway, complement proteins bind to antibodies to eventually destroy the invader; in an alternate complement pathway, complement proteins bind directly to the invader to destroy it. cytokine: A protein, such as interleukin, released by cells as part of the immune response. humoral immune response: A part of the innate immune system that relies on B-cells and the antibodies they produce to protect the body from invaders. The humoral immune response acts to destroy a specific entity, as opposed to passive responses which attack any invader. immunoglobulins: Also known as antibodies, they are protein molecules that attach themselves to antigens to serve as markers for macrophages. The five basic types of immunoglobulins are Immunoglobulin G (IgG), which is the most common type; Immunoglobulin M (IgM), which our bodies make when first exposed to a foreign agent; Immunoglobulin A (IgA), which is mainly found in the respiratory and urogenital tracts and in saliva, tears, and breast milk; Immunoglobulin E (IgE), which is involved in allergies; and Immunoglobulin D (IgD), which is found on the surface of B- and T-cells and which triggers the humoral immune response. inflammatory mediators: Part of the non-specific, reactive response, these are chemicals released by damaged cells to stimulate the body s inflammatory response. inflammatory response: The response of the body to invaders, it is caused by the action of plasma and leukocytes. innate immunity: The body s first line of defense, it includes non-specific, reactive responses and passive, barrier defenses. interleukins: Chemical messengers sent out by cells to attract helper cells during the immune response. Macrophages send interleukin messengers to attract T-cells; T-cells then send interleukin messengers to attract B-cells. Copyright

5 leukocytes: White blood cells that evolve into the phagocytic family of cells, and the lymphoid family of cells. Phagocytes and lymphocytes are the two basic types of leukocytes. Leukocytes release the chemicals that cause redness and swelling at the site of an infection. lymph: A fluid containing white blood cells that circulates throughout the lymphatic system to remove bacteria. lymph nodes: Organs found throughout the lymphatic system (but especially in the neck and trunk) that attract and retain white blood cells, and that filter out bacteria and other toxins from the lymph. Bacteria are often destroyed in the lymph nodes. lymphatic system: A body-wide system of organs, tissues, and fluids that are critical to the immune response. The thymus, spleen, bone marrow, lymph, lymph nodes, and Peyer s patches are all part of the lymphatic system. lymphocyte: A type of white blood cell that is crucial to the immune response. B-lymphocytes and T-lymphocytes work independently and together to battle infection. MHC: Major Histocompatibility Complex, the protein molecules on the surface of our cells that mark the cells as being a part of our own system (vs being invader cells). If a virus attacks the body, some of the virus antigens will appear on our cells surfaces at the MHC-I site; MHC-II on the surface of phagocytic cells will help to remove the virus. macrophage: A type of leukocyte that defends against antigens through the process of phagocytosis. Macrophages also rid the body of worn-out cells, and can produce complement proteins. Literally a large eater, it is a large white blood cell that ingests antigens. mast cell: A type of white cell found in connective tissue and in the nose, eyes, and throat that produces histamine, resulting in inflammation. memory B-cell: A type of B-cell that is formed after an infection; it remembers the threat if the same infection invades the body, and so is able to respond quickly to fight it. monocyte: A large white blood cell that transforms itself at the site of infection into a macrophage. neutrophil: A type of phagocyte that fights bacteria. Neutrophils are the most common type of phagoctye. non-specific, reactive response: A type of innate immunity, it acts to remove invading antigens that have made it past the passive, barrier defenses. Copyright

6 passive, artificial immunity: A way to acquire immunity to a particular disease by receiving serum from the blood of someone who has had that disease, and who has already developed antibodies to fight it. It differs from active artificial immunity in that it usually only lasts for a few months. A tetanus shot is an example of this type of immunity. passive, barrier defenses: A type of innate immunity including the skin, mucus membranes, tears, and saliva. passive, natural immunity: The type of immunity a baby receives through its mother via the mother s antibodies while the baby is still in the womb, or through breastfeeding. Peyer s patches: Lymphoid tissue found in the intestines that helps fight infection. phagocyte: A type of cell, such as the macrophage, that eats invading organisms. phagocytic family: A type of leukocyte cell that evolves into mononuclear leukoctyes (which eventually transform into macrophages), and polymorphonuclear leukocytes (which develop into basophils, neutrophils, and eosinophils). phagocytosis: The process in which a macrophage, after binding to an antibody, engulfs invading antigens, releasing a chemical that kills the foreign cell. Phagocytosis is part of the non-specific, reactive defenses of innate immunity. serum: Fluid taken from the tissues of immunized animals, containing antibodies and used to transfer immunity to another individual. spleen: A fist-sized organ of the lymphatic system located on the left side of the abdomen, it filters foreign organisms from the blood and destroys worn-out and damaged red blood cells. stem cell: A type of cell that is able to develop into different cells (such as B- and T-cells) that can then be used to repair the body. Two types of stem cells are embryonic and adult. T-cell: A type of lymphoctye that is especially critical to cell-mediated immunity. Helper T-cells stimulate B-cells to make antibodies; the Helpers then signal to cytotoxic (Killer) T-cells. Killer T-cells arrive and destroy infected cells by releasing perforins, which punch holes in the infected cell s wall, allowing fluid to rush in and then burst the cell. Suppressor T-cells inactivate the B-cells and other T-cells so that the immune response stops. thymus gland: A small organ of the lymphatic system located in front of the heart, it is critical in the development of T-cells. Copyright

7 Student Projects Describe the misadventures of a harmful microorganism entering the human body, and include the role played by B-cells, T-cells, interleukins, antibodies, etc. Choose one aspect of the immune response (such as inflammatory, humoral, or cell-mediated) to focus on in detail. Your presentation can be in the form of a story, play (with other students playing the part of leukocytes, etc), series of labeled drawings, flash animation, or any other type of media that gets the information across. Type 1 diabetes, asthma, allergies what are the causes and treatments of these diseases? Use this film as a starting point, then visit a Web site such as PhysOrg.com or ScienceDaily.com and look for news about advances in their treatment. If you know anyone who suffers from allergies or another immune disorder, interview them about it ( How long have you had this? How do you treat it? Are there times when symptoms seem worse? Better? ) Take all the information you gather cause of the disease, immunological response, current and possible future treatments, and eyewitness statements and write it up in the form of a news report or magazine article. Can the immune system really be strengthened by so-called superfoods (blueberries, broccoli, etc.), exercise, a healthy psychological outlook, and/or various supplements? How, specifically, would this work? Do you think these claims are valid? Should they be discounted if they have not been proven yet, or is further study warranted? Do some research on this, then present your findings in the form of a chart, poster, or spreadsheet. Pick an immunological topic that is currently in the news (e.g., organ transplant rejection, flu and HPV vaccines, bird flu, probiotics, peanut allergies, drug-resistant superbugs, HIV) and read a few articles about it. Do you feel that watching this program, with its information on T-cells, antibodies, and stem cells, has helped you better understand these medical issues? Do you think you d like to pursue a career in immunology, or in a healing profession? Discuss as a class the news items, and thoughts about career possibilities. The immune system has been the subject of a lot of controversy medical, philosophical, and even political (e.g., civil liberties). Divide the class into teams and conduct a series of debates on a controversy such as usage of stem cells, or vaccinations. Students should back up their positions with solid scientific research wherever possible. Copyright

8 Quiz 1. (is)(are) NOT classified as a passive, barrier defense. a) skin b) mucus membranes c) tears and saliva d) white blood cells 2. True or False? If a foreign body makes it past the skin, the non-specific, proactive defenses come into play, triggering the inflammatory response. 3. In phagocytosis, the macrophage. a) binds directly to, and then surrounds and destroys the foreign cell b) binds to an antibody, surrounds the invader, then releases complement proteins to kill the foreign cell c) fights off antibodies by surrounding them, then releasing complement proteins to kill them d) all of the above 4. Which of the following is NOT a type of white blood cell? a) phagocytic cells b) lymphocytes c) macrophage d) (all of these are) 5. create leukocytes and lymphocytes, which eventually create macrophages, T-cells, and. a) Stem cells; antibodies b) B-cells; antigens c) Antigens; antibodies d) Antibodies; stem cells 6. Which of the following is NOT a part of the lymphatic system? a) the spleen b) the thymus c) the thyroid d) the blood marrow 7. The key components of the humoral immune response are, and the antibodies also called that these produce. a) T-cells; antigens b) the lymph nodes; Helper T-cells c) B-cells; immunoglobulins d) the spleen and thymus; interleukins Copyright

9 8. (Circle the correct term.) Macrophages recognize an invader, then send out interleukins to attract [B-cells / Helper T-cells / Killer T-cells / Suppressor T-cells]. Helper T-cells bind to the antigen-presenting site on the macrophage, then send out interleukins to attract [B-cells / Helper T-cells / Killer T-cells / Suppressor T-cells] and [B-cells / Helper T-cells / Killer T-cells / Suppressor T-cells]. When the [B-cells / Helper T-cells / Killer T-cells / Suppressor T-cells] arrive, the T-cells signal them to create antibodies. The antibodies, along with the aid of [B-cells / Helper T-cells / Killer T-cells / Suppressor T-cells], destroy the invading cell. Now the [B-cells / Helper T-cells / Killer T-cells / Suppressor T-cells] signal the attack to stop. 9. Cell-mediated immunity involves T-cells, and the Major Histocompatibility Complex (MHC). The MHC. a) allows the immune system to tell its own cells apart from invading cells b) aids in the replication of T-cells c) disguises antigens to protect them from Killer T-cells d) signals interleukins to begin their work 10. What s the difference between receiving a vaccination (a type of active, artificial immunity), and serum (a type of passive, artificial immunity)? a) A serum is created by the body s own cells in response to infection; vaccinations use artificially-created antibodies. b) Serums come to us via the placenta while in the womb, while vaccinations come immediately after birth. c) A serum comes from someone who has already had a specific disease and has developed antibodies against it. It does not last as long as a vaccination, because it does not provoke the body to create its own immune response. d) The body can live without vaccinations, but not without antibiotic serums. 11. Here is an example of active, natural immunity: If you had chicken pox as a child, it is due to that you will not get it again as an adult. a) choosing a healthy lifestyle b) the production of memory B-cells that remember this infection c) the development of organic serums d) the production of stem cells Copyright

10 12. Autoimmune disease such as allergies and Type 1 diabetes occur when. a) an over-active immune response causes over-production of antibodies that attack the body s own healthy cells b) the immune system has been compromised by over-production of Suppressor T-cells c) mast cells attack the lymph nodes d) the lymphatic system becomes overrun with pollen and other histamines 13. When pollen enters the body, mast cells in the nasal passages release histamine, causing sneezing and a runny nose. Allergy medications work by blocking. a) the production of mast cells b) this inflammatory response c) the anaphylactic response d) the production of mucus Copyright

11 Answers to Quiz 1. d) white blood cells 2. False (it s the reactive, not proactive defenses that come into play). 3. b) binds to an antibody, surrounds the invader, then releases complement proteins to kill the foreign cell 4. d) (all of these are) 5. a) Stem cells; antibodies 6. c) the thyroid 7. c) B-cells; immunoglobulins 8. (Circle the correct term.) Macrophages recognize an invader, then send out interleukins to attract Helper T-cells. Helper T-cells bind to the antigen-presenting site on the macrophage, then send out interleukins to attract B-cells and Killer T-cells. When the B-cells arrive, the T-cells signal them to create antibodies. The antibodies, along with the aid of Killer T-cells, destroy the invading cell. Now the Suppressor T-cells signal the attack to stop. 9. a) allows the immune system to tell its own cells apart from invading cells 10. c) A serum comes from someone who has already had a specific disease and has developed antibodies against it. It does not last as long as a vaccination, because it does not provoke the body to create its own immune response. 11. b) the production of memory B-cells that remember this infection 12. a) an over-active immune response causes over-production of antibodies that attack the body s own healthy cells 13. b) this inflammatory response Please send comments, questions, and suggestions to custserv@film.com. Copyright