Chapter_32_The_Lymphatic_and_Immune_System

nullnullPowerPoint® presentation to accompany: Medical Assisting Third Edition Booth, Whicker, Wyman, Pugh, ThompsonThe Lymphatic and Immune SystemsLearning OutcomesLearning Outcomes32.1 List the pathways and organs of the lymphatic system and give their locations. 31.2 Define lymph and tell how it is circulated in the body. 31.3 Define the terms infection, pathogen, and antigen. 31.4 List and describe the nonspecific body defense mechanisms. 31. 5 Explain the signs and causes of inflammation. Learning Outcomes (cont.)Learning Outcomes (cont.)32.6 Explain what is meant by body defenses. 32.7 Define B cells and T cells and describe their locations and functions. 32.8 Explain the importance of MHC proteins. 32.9 List the different types of T cells and describe their functions. 32.10 Explain how antibodies fight infection.Learning Outcomes (cont.)Learning Outcomes (cont.)32.11 List the different types of antibodies and tell how they differ. 32.12 Define complement proteins and give their function. 32.13 Explain the difference between the primary immune response and secondary immune response. 32.14 Explain the four different types of acquired immunities. 32.15 Describe the function of a vaccine.Learning Outcomes (cont.)Learning Outcomes (cont.)32.16 Define the terms cancer and carcinogen. 32.17 Describe how cancers are diagnosed and treated. 32. 18 Explain how cancers are classified. 32.19 Describe how allergies develop. 32.20 Describe the causes, signs and symptoms, and treatments of other common immune disorders.Introduction Introduction Immune system Protects the body against Bacteria Viruses Fungi Toxins Parasites CancerLymphatic system Works with immune system to remove disease-causing agents Organs Thymus Spleen Lymph nodesThe Lymphatic SystemThe Lymphatic SystemNetwork of connecting vessels Collects fluid (lymph) between cells and returns it to bloodstream Picks up lipids from digestive organs and transports them to blood stream Functions to defend the body against pathogensLymphatic System: PathwaysLymphatic System: PathwaysLymphatic capillaries Extend into interstitial spaces Permeable, thin walls pick up fluid, now lymph Delivers lymph to lymphatic vessels Lymphatic vessels Deliver lymph to lymph nodes Cells in nodes can remove pathogens from lymph and start an immune response Leaves nodes through efferent lymphatic vesselsLymphatic System: Pathways (cont.)Lymphatic System: Pathways (cont.)Lymphatic trunks Receive lymph from efferent lymphatic vessels Deliver it to Lymphatic collecting ducts Thoracic duct Left side of head and neck, left arm, left side of thorax, entire abdominopelvic area, and both legs Right lymphatic duct Right side of head and neck, right arm, and right side of chestLymphatic System: Tissue Fluid and LymphLymphatic System: Tissue Fluid and LymphInterstitial fluid Fluid in spaces between cells that has leaked from blood capillaries and has not been picked up by body cells High in nutrients, oxygen, and small proteins Becomes lymph Pushed through lymphatic vessels by squeezing action of neighboring skeletal muscles and breathing movementnullLymphatic System: NodesLymphatic System: NodesSmall, glandular structures Located along paths of larger lymphatic vessels Afferent lymphatic vessels – Lymph to node Efferent lymphatic vessels – Lymph from node Lymphatic System: Nodes (cont.)Lymphatic System: Nodes (cont.)More lymph enters than can leave at one time Cells in nodes Macrophages – digest unwanted pathogens Lymphocytes – start an immune response against pathogen Nodes can generate some lymphocytesLymphatic System: The Thymus and SpleenLymphatic System: The Thymus and SpleenThymus Soft, bi-lobed organ Located just above the heart in the mediastinum Large in children, shrinks as we age Functions Same as lymph nodes Also produces lymphocytes Produces thymosin – stimulates production of lymphocytesLymphatic System: The Thymus and Spleen (cont.)Lymphatic System: The Thymus and Spleen (cont.)Spleen Largest lymphatic organ Located in the upper left quadrant of abdominal cavity Functions Filters blood similarly to lymph nodes Removes worn-out red cells If removed (splenectomy), liver takes over most of its function Apply Your KnowledgeApply Your KnowledgeWhat are the lymphatic collecting ducts and what area do they drain?ANSWER: The collecting ducts are: Thoracic duct, which drains the left side of the head and neck, left arm, left side of thorax, entire abdominopelvic area, and both legs; and the right lymphatic duct, which drains the right side of the head and neck, right arm, and right side of the chest.Defenses Against DiseaseDefenses Against DiseaseInfection The presence of a pathogen in or on the body Pathogen A disease-causing agent Innate immunity Nonspecific defenses to protect against pathogensNonspecific defenses Species resistance Mechanical barriers Chemical barriers Phagocytosis Fever Inflammation Defenses Against Disease: Specific DefensesDefenses Against Disease: Specific DefensesImmunities Protect against very specific pathogens Antigens Foreign substances in the body Haptens Foreign substances too small to start an immune response by themselvesOther substances Proteins – antibodies and complements WBCs – lymphocytes and macrophages Lymph system Cytokines – assist in immune response regulation Monokines – increase B cell production and stimulate WBC productionDefenses Against Disease (cont.)Defenses Against Disease (cont.)Two major types of lymphocytesB Cells and T CellsRecognize antigens in the bodyT Cells Cell-mediated response Bind to antigens on cells and attack them directly Secrete lymphokines that increase T cell production and directly kill cells with antigensB cells Respond to antigens by becoming plasma cells Plasma cells make antibodies Memory B cells produce stronger response with next exposure to antigennullDefenses Against Disease (cont.)Defenses Against Disease (cont.)T cell activation Begins when macrophage ingests and digests pathogen with antigen on it Antigens are placed on cell membrane of macrophage T cell recognizes and binds to antigen and the major histocompatibility complex (MHC) on the surface of the macrophage Now can divide to form other types of T cellsDefenses Against Disease (cont.)Defenses Against Disease (cont.)Types Cytotoxic T cells Protect body against viruses and cancer cells Helper T cells Increase antibody formation, memory cell formation, B cell formation, and phagocytosis Memory T cells Remember the pathogen that activated original T cell Later exposures trigger an immune response more effective than initial responseDefenses Against Disease (cont.)Defenses Against Disease (cont.)Natural killer (NK) cells Type of lymphocyte Primarily target cancer cells Kill on contact Do not recognize a specific antigenApply Your KnowledgeApply Your KnowledgeIdentify whether each item refers to T cells, B cells, or NK cells: ___ Primarily target cancer cells ___ Respond to antigens by becoming plasma cells ___ Must be activated to respond to an antigen ___ Bind to antigens on cells and attack them directly ___ Kill on contact ___ Need macrophages and MHC for activation ___ Make antibodies against specific antigenBNKTTTBRight on Target!AntibodiesAntibodiesAlso called immunoglobulins IgA Prevents pathogens from entering body IgD Found on B cell membranes Thought to control B cell activity IgE Found with IgA Involved in triggering allergic reactionsAntibodies (cont.)Antibodies (cont.)IgG Recognizes bacteria, viruses, and toxins Activates complements IgM Large and binds to antigens on food, bacteria, or incompatible blood cells Activates compliments Antibodies (cont.)Antibodies (cont.)Actions that occur when antibodies bind to antigens Allow phagocytes to recognize and destroy antigens Cause antigens to clump together, causing them to be destroyed by macrophages Cover the toxic portions of antigens, making them harmless Activate complement Group of proteins in serum that attack pathogens by forming holes in them Attract macrophages to pathogens and can stimulate inflammationApply Your KnowledgeApply Your KnowledgeWhat are the possible actions that occur when antibodies bind to antigens?ANSWER: Possible actions include: They allow phagocytes to recognize and destroy antigens. They make antigens clump together, causing them to be destroyed by macrophages. They cover the toxic portions of antigens to make them harmless. They activate complements. Very Good!Immune Responses and Acquired ImmunityImmune Responses and Acquired ImmunityPrimary immune response occurs with first exposure to antigen Slow process Memory cells are formed Secondary immune response with next exposure to same antigen Quick and carried out by memory cells Usually prevents person from developing disease from the antigenImmune Responses and Acquired Immunity (cont.)Immune Responses and Acquired Immunity (cont.)Naturally acquired active immunity Natural exposure to antigen – having an illness Makes antibodies and memory cells Long-lasting Artificially acquired active immunity Injected with pathogen – immunizations Makes antibodies and memory cells Long-lastingImmune Responses and Acquired Immunity (cont.)Immune Responses and Acquired Immunity (cont.)Naturally acquired passive immunity Acquired from mother Breast milk Placenta Short-lived Artificially acquired passive immunity Injected with antibodies (such as antivenom) Short-livedApply Your KnowledgeApply Your KnowledgeANSWER: Immunization is an artificially acquired immunity because a person develops this immunity by being injected with a pathogen and then making antibodies and memory cells against the pathogen. After you give an immunization to a 2-year-old, her mother asks you why this will work to prevent her from getting a disease.Major Immune System DisordersMajor Immune System DisordersCancer Uncontrolled growth of abnormal cells form malignant tumors 200 known types Treatment based on stage 0 – very early; cancer cells localized I – spread to deeper layers or some in surrounding tissues II – spread to surrounding tissues but contained in primary site III – spread beyond primary site into nearby areas IV – spread to other organs Recurrent – reappeared after treatmentMajor Immune System Disorders (cont.)Major Immune System Disorders (cont.)Allergies Immune response to an allergen Can be excessive IgE antibodies bind to allergens and stimulate mast cells to release histamine and heparin Triggers allergic response Allergy shots Small amounts of allergen stimulates production of IgG to prevent IgE from binding to antigen IgG antibodies do not stimulate mast cells, so immune response is not generatedMajor Immune System Disorders (cont.)Major Immune System Disorders (cont.)Signs/symptoms Inhaled allergens – runny nose, sneezing, coughing, wheezing Ingested allergens – nausea, vomiting, diarrhea Skin allergens – rashes Allergens in blood – most life-threatening; can affect many organs Treatment Antihistamines, decongestants – OTC or prescription Epinephrine for anaphylaxis – vasoconstriction, increasing BP Anaphylaxis – life-threatening responseCommon Immune System Disorders Common Immune System Disorders Autoimmune disease Body attacks its own antigens Examples Scleroderma Rheumatoid arthritis Multiple sclerosis Glomerulonephritis Chron’s disease Diabetes mellitus, type ICommon Immune System Disorders (cont.)Common Immune System Disorders (cont.)Common IS Disorders (cont.)Common IS Disorders (cont.)Apply Your KnowledgeApply Your KnowledgeMatching: ___ Immune response to a substance A. CFS ___ Blockage of lymphatic vessels B. SLE ___ “Kissing disease” C. Cancer ___ “Butterfly” rash on face D. Autoimmune disease ___ Severe tiredness E. Lymphedema ___ Uncontrolled growth of abnormal cells F. Mononucleosis ___ Body attack its own antigens G. AllergyGFEDCBAANSWER:In SummaryIn SummaryImmune system is the body’s major line of defense Primary function – protect against infection, toxins, and cancer Specific or nonspecific defenses Lymphocytes are major cells of immune system Immune response may be primary or secondary Medical assistant must understand immune system Aseptic technique Infection control Educate patientsEnd of Chapter End of Chapter Thought is an infection. In the case of certain thoughts, it becomes an epidemic. ~Wallace Stevens