The Immune System - Physical Therapy Implications PDF

The Immune System: Physical Therapy Implications PTHP 8242: Medical Conditions II Vanessa J. Everett, PT, DPT, GCS Adapted from: Margaret Blagg, PT, DPT, WCS Objectives Discuss and differentiate between innate and acquired immunity. Identify the role of humoral- an...

The Immune System: Physical Therapy Implications PTHP 8242: Medical Conditions II Vanessa J. Everett, PT, DPT, GCS Adapted from: Margaret Blagg, PT, DPT, WCS Objectives Discuss and differentiate between innate and acquired immunity. Identify the role of humoral- and cell-mediated immunity. Identify therapeutic clinical importance of immune functions. Explain the role and impact of HLA antigens and autoimmune disease. Discuss the process of infectious disease, the chain of transmission, and aspects of control and the significance in physical therapy. Immune System Function Protects the body from possibly harmful substances by recognizing and responding to antigens Failure of the system can result in localized or systemic infection Responses can be harmful as in transplant rejection Excessive response can result in hypersensitivity, immune complex disease, or autoimmune disease Major Histocompatibility Complex Proteins Cell markers on body cells that are unique to the individual are major histocompatibility proteins FYI II Commonly called human leukocytic antigens (HLAs) Determine which antigens an individual responds to and how strongly AnythinrewarrenBy theBonmaresaresponseto theimmunesystemthat Allow immune cells to recognize each other and communicate Inherited and can predispose an individual to certain diseases Major Histocompatibility Complex Proteins Class I MA RM HLA-A, HLA-B, HLA-C THE Found on nucleated cells and platelets Class II HLA-DP, HLA-DQ, HLA-DR Found on monocytes, macrophages, B cells, activated T cells, vascular endothelial cells, Langerhans’ cells, and dendritic cells Class III Complement proteins C2, C4, and factor B Types of Immunity Innate immunity First line of defense Non-specific and non-adaptive Physical barriers and bloodborne Acquired immunity Specific and adaptive Recognizes and destroys foreign substances Increasing strength and speed of reaction to each encounter Humoral and cell-mediated BCEU T CEV Innate vs. Adaptive (Acquired) Immunity Inflammatory response: resident cells Tissue injury (cut in the skin) Microorganisms get introduced into body because of the breach in first line of defense (skin) Activated macrophages phagocytose foreign matter Activated macrophages release cytokines (IL-1, TNF) MASTCEU ACTUATION Mast Cells release histamine & eicosanoids WCAU prevent neutropunapoptosis from Causes vasodilation and increased vascular permeability Systemium ip.iecmanIae RELEASEmom wruso Leads to Cardinal signs of inflammation: Rubor, Calor, Tumor and Dolor II T.IE river 9 PAN VED WANT JEW  Complement Defensive Proteins move into the local area (from increased vasodilation and increased capillary permeability) First complement protein (inactive): comes into contact with a bacterial cell – makes it an active enzyme Membrane attack complex (MAC - is 1 result of this activation) When this activation happens – it splits in two 1: part of complement molecule: remains bound to bacterial cell - promotes phagocytosis by neutrophils & monocytes/macrophages Am 2: soluble mediator that becomes a chemo-attractant – blood cells follow these and hone in on the source – leads them where to go Innate Immunity Innate Immunity 1st Line Exterior Defenses Skin is first and best line of protection Body openings have their own unique protection Lysozymes in tears Waxy secretions in ear canal Nasal hair Cough and sneeze reflex Stomach acid Acidic pH of vaginal secretions and urine Innate Immunity 2nd Line Cellular Defense MATT KNEW Leukocytes WB ENGULF Principle phagocytes – neutrophils and monocytes/macrophages Cells that release inflammatory mediators Basophils, mast cells, and eosinophils UNIA I GW If VINS SEND IN GRANNYAS Natural killer cells BREAK DOWN EXTERNAL Interdigitating dendritic cells Lymphoid Tissue Five Types of Leukocytes RADIATION MEMO SnortLiver 2 3Days White Blood Cell Count Leukocyte Function Absolute Count % of WBC (cells/mm3) Neutrophils Phagocytose microorganisms in the 1800-7000 50%-60% acute phase Basophils Release histamines during allergic 0-200 < 1% reactions Eosinophils Attack parasites and play a role in 0-450 < 3% asthma and allergic reactions Monocytes Clean up debris after neutrophils 200-800 1%-9% (macrophages) are done Lymphocytes (B Produce antibodies, fight tumor 1500-4000 30%-40% cells and T cells) cells, and respond to viral infection Total WBC 4500 – 11,000 Neutrophil Polymorphonuclear cells (PMNs) Derived from bone marrow and increase in response to infection, inflammation, and physical stress Short lived and directly kill invading tissue but also damages host tissues AUMULATION Of THEM CAN CANpuss Neutrophil Neutrophilia Abnormally high number of circulating neutrophils Associated with acute inflammation May result from chronic myelogenous leukemia, a cancer of blood-forming tissues Neutropenia Abnormally low number of neutrophils Associated with immunodeficiency or exposure to harmful chemicals or drugs Significantly increases the risk of infection Macrophage Circulating monocytes mature into macrophages when they migrate into the tissue Longer living and appear after neutrophils to clean debris from neutrophils and any organisms too large for the neutrophils After phagocytosis, become antigen-presenting cells Presents antigen’s epitope to helper/inducer lymphocyte, or the T4 (CD4) lymphocyte via interleukin-1 Participate in defense against tumor cells Macrophage Monocytosis Increase number of circulating monocytes Occurs in viral and bacterial infection, chronic inflammation, and in stress response Extremely high count occurs with sepsis Monocytopenia Decreased count of circulating monocytes Occurs with immunosuppressive drugs (e.g. glucocorticoids) Eosinophil Derived from bone marrow Circulate in blood stream 8-12 hours Multiply in response to parasitic infection and allergic disorders Involved in allograft rejection and neoplasia Destroys large organisms by getting close and releasing contents of granules I UNCONTROWN are Eosinophil Eosinophilia Increase in circulating eosinophils Parasitic infestation of intestines, collagen vascular disease (RA), malignant disease, or extensive skin disease Seen with use of certain drugs like penicillin Most common cause is allergic asthma Basophil Least common of WBCs Function similarly to mast cells Release histamine, vasodilation Increase blood supply to affected area Present in allergic symptoms Contains anticoagulant heparin Basophil Basophilia Elevated blood count of basophils Uncommon but seen in some forms of leukemia or lymphoma Basopenia Decreased blood count of basophils May be associated with uticaria TWIN CASts curve Mast Cell Releases histamine which acts as a vasodilator and increases vascular permeability, and heparin an anticoagulant In anaphylaxis, body-wide degranulation of mast cells leads to vasodilation and severe symptoms Implicated in pathophysiology of rheumatoid arthritis and multiple sclerosis Mature at site of damage STIMULATE RESIDENT CEUs WAY Inflammatory Mediators Complement System 30 serum proteins designed to help immune function Released by cells and affect the behavior of other cells Opsonization Coats organisms so they can be more easily phagocytosed May wall off the organism Cytokines Non-antibody proteins that act as messengers between cells and mediate biologic response Interferons Cytokine that is produced by virally infected cells to protect surrounding cells Natural Killer Cell Large granular lymphocytes that are neither B- nor T-lymphocytes Kill viruses, other infected cells, and tumor cells Bind with the target cell and interact with receptors to detach or activate Releases cytotoxic granules and secretes cytokines Adaptive Immunity Adaptive Immunity Recognizes different organisms and kills them Rapidly responds with strong reaction to repeated exposure Lymphocytes are specific for a given antigen T- and B-cells migrate throughout the body Two types of adaptive immune responses VE Humoral immunity (immunoglobulin-related immunity)β Cell-mediated immunity (T-cell immunity) Develops a highly diverse group of antigen receptors Antigens Any foreign substance that does not have cell markers of the individual (MHC) Bacteria, viruses, fungi, parasites, foreign tissue, or large protein molecules Epitopes protrude from antigen surface and combine with antibodies, capable of creating immune response 3 types of antigens: exogenous, endogenous, and autoantigens Humoral Immunity B lymphocytes (B cells) Originate in bone marrow and circulate through extracellular fluid Coated with immunoglobulin Contains an antibody that recognizes specific antigen Mediated by antibodies present in body fluids or secretions B-cells change to plasma cells or memory B-cells after coming in contact with the antigen Circulate in the blood, lymph system, and tissues for a year or longer Particularly useful against bacterial infection Humoral Immunity Plasma Cell Produce and secrete a specific antibody (immunoglobulin) to a specific antigen Immunoglobulin function Attack and destroy/neutralize antigens via agglutination Activate the complement system Activate anaphylaxis by releasing histamine Stimulate antibody-mediated hypersensitivity Antibodies Serve to tag cells or microorganisms to alert other defensive cells Bind to the antigen via the epitope Each antibody fits only one epitope 5 classes of antibodies IgG – 75%-85% IgM – 5%-10% IgA – 10-15% IgD IgE Antibodies IgM IgA Predominates primary immune response Defends external surfaces Largest immunoglobulin Found on mucous membranes and in Almost exclusively blood and lymph secretions vasculature IgD IgG Predominant antibody on the surface of Major antibacterial and antiviral antibody B lymphocytes The predominant immunoglobulin in Serves mainly as antigen receptor blood IgE Protection of newborn in first 6 months Functions during allergic reactions by Synthesized during secondary immune activating mast cells and releasing response histamine Associated with allergies, anaphylaxis, extrinsic asthma, and urticaria Vaccinations Inject killed microorganism or harmless antigen Effector response is slow and weak, but it is not needed to stay healthy Important aspect DOES happen – which is the generation of memory cells When infection may occur by the natural, pathogenic microorganism occurs, the effector response is fast and strong. Active vs. passive immunity Cell-Mediated Immunity T-cells originate in bone marrow and mature in the thymus Recognizes organisms that are hiding inside the cells where antibodies cannot reach them Activated cells produce additional lymphocytes called sensitized T- cells Helper T-cells (CD4 or T4) assist B-cells to mature and produce antibodies by secreting lymphokines Regulatory/Suppressor T-Cells suppress activation of immune system and prevent autoimmune disease T-Cell Function Helps B-cells produce antibodies Activates macrophages and helps them destroy large bacteria Helps cytotoxic T-cells (CD8) recognizes and destroy virally infected cells Helps NK cells kill infected cells Cell-Mediated Immunity TUE Responsible for rejection of transplanted tissue, hypersensitivity reactions, and some autoimmune Basis for many skin tests (TB and allergy) Cannot be transferred to another person T-cell function compromised by HIV and AIDS, stress, malignancy, general anesthesia, thermal injury, surgery, diabetes, and immunosuppressive drugs Pathway of Lymphocyte Maturation CELLS PROCESS Normal Range NK Cells Lysis of virally infected cells and tumor cells Innate 02-03% Helper T Cells Release cytokines and growth factor that Adaptive 28-59% (CD4 T Cells) regulate other immune cells Cellular Cytotoxic T Cells Lysis of virally infected cells, tumor cells, and Adaptive 13-32% allografts Cellular Regulatory (Suppressor) T Immunoregulation, modulate the immune Adaptive 02-08% Cells system, shuts down T-cell mediated immunity, Cellular prevents autoimmune response B Cells Secretion of antibodies Adaptive 18-47% Humoral Lymphocyte Lymphocytopenia Decrease in number of lymphocytes Seen in HIV and leukemia Lymphocytosis Increase in number of lymphocytes Seen in viral infections Immune System Summary Factors Affecting Immunity Aging Concurrent illnesses and disease Sex and hormone influences Medications, Nutrition/malnutrition immunosuppressant Environmental pollution Hospitalization, surgery, general anesthesia Exposure to toxic chemicals Splenectomy Trauma Stress; psycho-spiritual well Burns being Sleep disturbance Socioeconomic status Factors Increasing Exposure to Pathogens Iatrogenic Sexual practices Urinary catheters Recreational drug use Nasogastric tubes Endotracheal tubes Chest tubes Intracranial pressure monitor External fixators Implanted prostheses Diseases of the Immune System Immunodeficiency: immune response is absent or depressed Acquired Immunodeficiency Chronic Fatigue Syndrome: interactions between CNS, immune system, hormonal regulation, and psychosocial Hypersensitivity Disorders: exaggerated or inappropriate immune response Autoimmune Disease: body fails to distinguish self from non-self and may be associated with HLA Antigens Isoimmune Disease: tissue graft and organ transplant rejection Immunology and Infections Infectious Disease 1950-1980 communicable infectious disease was under control In the 1970s-1980s new infectious agents appeared and previously controlled diseases have reemerged Multiple factors Misuse and overuse of antibiotics Large numbers of children in daycare centers Sicker populations in hospitals Agricultural reliance on antibiotics Climate change Increased human mobility Infectious Disease Process by which an organism establishes a parasitic relationship with its host Signs & symptoms vary depending on type of organism and the system affected Once agent is transmitted, three possible outcomes Contamination of body surface Subclinical infection with no apparent symptoms Development of infectious disease Period of communicability usually precedes symptoms and continues through part of clinical disease Chain of Transmission Transmission Chain Factors Pathogen or agent Viruses, mycoplasmas, bacteria, rickettsiae, chlamydiae, protozoa, fungi, prions Reservoir Human beings (clinical cases, subclinical cases, and carriers) Animal, arthropod, plant, soil, food, organic substance Portal of exit Genitourinary tract, GI tract, respiratory tract, oral cavity, open lesion, blood, vaginal secretions, semen, tears, excretions (urine, feces) Transmission Contact (direct or indirect) Airborne (float on air currents and remain suspended for hours; small particles) Droplet (fall out within 3 feet of source; large particles) Vehicle (through a common source such as water or food) Vectorborne (carried by insects or animals) Modes of entry Ingestion, inhalation, percutaneous injection, transplacental entry, mucous membranes Susceptible host Specific immune reactions Nonspecific body defenses Host characteristics: age, sec, ethnic group, heredity, behaviors Environmental and general health status