HLTH 335 1st Edition Lecture 2 Chapter 2: Immunity and DiseaseObjectives:-Define immunity.-Compare and contrast nonspecific and specific immunity.-Describe hypersensitivity.-Define autoimmunity and autoantibodies.-Discuss stress and immunity.-Discuss age and immunity.Immunity:-The ability of the body to defend itself against infectious agents, foreign cells, and abnormal body cells. -Nonspecific Defenses (Innate Immunity): Barriers, Phagocytosis, NK cells, Fever, Interferon, Inflammation.-Specific Defenses (Acquired Immunity): Cell-Mediated & Humoral.Non-Specific Defense and Innate Immunity:-Physical and chemical barriers-Intact skin (physical).-Skin produces secretions (tears, sweat, saliva, oils) that contain chemicals that can destroy foreign invaders.-Phagocytosis-Leukocytes destroy infectious agents through phagocytosis (cell eating: they engulf and digest invading materials).-Natural Killer (NK) Cells:-One type of leukocyte that works by recognizing abnormal membranes.-Fever (raise in body temperature) stimulates phagocytosis.-Increases metabolism, inhibits multiplication of certain organisms.-Interferons are anti-viral proteins that boost immunity.-They remain after viral infections in some cells; stimulate the cells to resist infection.-They increase activity of NK cells.-They “interfere” with virus replication.Inflammation:-Tissue trauma is caused by chemical, physical, or pathogenic agents; trauma (injury); allergens; foreign substances.These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.-Tissue trauma  Histamine Release  Hyperemia (Heat)  Dilation of Arterioles, and Capillaries  Increased Capillary Permeability- Hyperemia (Heat), Dilation of Arterioles & Capillaries, and Increased Capillary Permeability  Movement of Neutrophils In and Out of Blood Vessels & Leukocytosis.- Movement of Neutrophils In and Out of Blood Vessels  Monocytes clean up debris (phagocytosis), Inflammatory Exudate (produces fibrin) Coagulation (Blood-Clotting)Review: Immunity:-The ability of the body to defend itself against infectious agents, foreign cells, and abnormal body cells. -Nonspecific Defenses (Innate Immunity): Barriers, Phagocytosis, NK cells, Fever, Interferon, Inflammation.-Specific Defenses (Acquired Immunity): Cell-Mediated & Humoral.**Acquired Immunity involves the lymphatic system.Acquired Immunity:-Acquired immunity is the body’s specific response to a specific pathogen.-Passive acquired immunity results when a person receives protective substances produces by another human or animal.-Active acquired immunity develops following direct exposure to the pathogenic agent.-Immunizations and vaccinations are special types of active acquired immunity.Cellular (Cell-Mediated) Immunity-Involves the production of T cells and natural killer (NK) cells.-These defense cells are cytotoxic.-They physically attack and destroy pathogenic cells.Humoral Immunity-Refers to the production of B lymphycytes, also called B cells.-B cells respond to antigens by producing a protective protein, an antibody.-Antibodies combine with the antigen to form an antigen – antibody complex.-It either targets the foreign substance for phagocytosis, or prevents the infectious agent from damaging healthy cells.The Body’s Defense Mechanisms-Immune System:-Non – Specific (Innate): Barriers, Phagocytosis, NK cells, Fever, Interferon & Inflammation.-Specific (Adaptive) “Acquired Immunity”: Humoral Response  B – lymphocytes  produced in bone marrow. Cell – Mediated Response (cytotoxic)  T – lymphocytes  produced in thymus.Hypersensitivity (ALLERGY!!)-Diseases that occur as a result of immune response.-An extreme immune response to a harmless antigen (a.k.a. allergen).-Types of hypersensitivity: Type I (immediate), Type II (cytotoxic), Type III (immune-complex), Type IV (delayed). Not in order of seriousness.Type I Hypersensitivty-Most common.-Localized.-IgE binds to mast cells & triggers histamine production.-Histamine triggers the inflammation process.-Antihistamines used for treatment.-Decongestant can help, but won’t stop process.Type II Hypersensitivity-Cytotoxic (very serious!)-IgM or IgG causes the destruction of cells.-Ex: Response to an incompatible blood transfusion.**Body is opposed to blood aka deadly.Type III Hypersensitivity-Immune – complex hypersensitivity.-Antigens combine with MANY antibodies, forming a soluble mass (immune complexes).-The complexes can deposit in tissues and vessels and trigger inflammation and tissue destruction.-Ex: glomerulonephritis (deposits in kidney after a strep infection).Type IV Hypersensitivity-Delayed hypersensitivity-Take time after exposure to develop/react.-Ex: Reactions to poison ivy/oak, contact dermatitis from wearing latex gloves.Autoimmunity-When the immune system attacks the body’s own tissue.-Immune response normally recognizes the difference between the individual’s own tissues and those of invaders; this is known as tolerance.-Autoimmune diseases occur when individuals develop antibodies to their own tissues or self-antigens.-Autobodies are those that attack the individual’s own tissues.Systemic Lupus Erythematosus-Noncontagious inflammatory disease that takes one of two forms: mild or severe.Symptoms begin suddenly or insidiously.-Rash and skin sensitivity to sunlight.-Joint and muscle pain, with lymph node enlargement.-Severe deterioration of collagenous connective tissue.-Systematic treatment of symptoms.-May be fatal.Lupus stats-1.5 million Americans affected.-More than 5 million worldwide.-90% of lupus patients are women.-Diagnosis usually occurs between ages of 15 to 44.Stress and the Immune System-(Stress  Increased production of epinephrine and norepinephrine  Increased production of serum cortisol)  Decreases production & numbers of lymphocytes; inhibits lymphocyte maturation. RESULT: Decreased immunity.Age and the Immune System-By middle age, the thymus is only about 15% of its maximum size.-The diversity of T lymphocytes is reduced with age.-Common problems include increased infection risk, decreased ability to fight disease, and autoimmune disorders.Summary-Two types of immunity to protect us from foreign invasion.-Nonspecific (Innate): Inflammation is the key player.-Specific (Acquired): Lymphatic System, Humoral vs. Cell-Mediated (Interaction of these produces