1 / 39

Disorders of the Immune System

Disorders of the Immune System. Disorders of Immune System. Defenses against infection Immune system disorders Autoimmune diseases Immunodeficiency. Defenses Against Infection. Barriers (non-specific) Skin Mechanical removal (coughing, vomiting, diarrhea, skin sloughing) Normal flora

Download Presentation

Disorders of the Immune System

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Disorders of the Immune System

  2. Disorders of Immune System • Defenses against infection • Immune system disorders • Autoimmune diseases • Immunodeficiency

  3. Defenses Against Infection • Barriers (non-specific) • Skin • Mechanical removal (coughing, vomiting, diarrhea, skin sloughing) • Normal flora • Antimicrobial secretions • Inflammation (non-specific) • Immunity (specific)

  4. Immune Response • Natural vs. Acquired • Active vs. Passive • Primary vs. Secondary • Humoral vs. Cell-Mediated

  5. Humoral Immunity • B Lymphocytes (Plasma Cells) • Produced in bone marrow • Make antibodies (immunoglobulins)

  6. Antibodies • Protein molecules produced by B-cells • Specific shapes allow binding to specific molecules (antigens) • Allow body to respond defensively to presence of specific potential threats

  7. Antibody Types • IgG • IgM • IgA • IgD • IgE

  8. IgG • Most common antibody type • Only antibody that crosses placenta • Prime mediator of secondary immune response • Principal defender against bacteria, viruses, and toxins

  9. IgM • Macroglobulin • Confined to bloodstream • First antibody to appear in response to presence of antigen • Agent of primary immune response

  10. IgA • Secretory antibody • Found in saliva, tears, respiratory secretions, GI tract secretions • Frontline bacterial, viral defense

  11. IgD • Role not fully understood • Low serum levels • High concentrations on B-cells • May act as receptors that trigger production of other antibodies

  12. IgE • Very low serum levels • Primarily bound to mast cells in tissues • Controls allergic response • Prevents parasitic infections

  13. Antigen-antibody binding initiates reactions that: • Neutralize bacterial toxins • Neutralize viruses • Promote phagocytosis • Activate components of inflammatory response

  14. Cell-Mediated Immunity • T Lymphocytes • Originate in bone marrow • Altered by passage through thymus • Responsible for mediation of cellular immunity

  15. T Lymphocyte Types • Helper cells (T4 cells) • Cytotoxic cells (Killer T cells) • Suppressor cells • Memory cells

  16. Helper T-Cells • Master “on-switch” of immune system • Recognize antigens • Secrete lymphokines that activate all other immune system cells • Stimulate B-cells to begin antibody production

  17. Cytotoxic (Killer) T-Cells • Respond to presence of antigens and lymphokines produced by T-4 cells • Seek out, bind to, and destroy: • Cells infected by viruses • Some tumor cells • Cells of tissue transplants • Can deliver lethal hits on multiple cells in sequence

  18. Suppressor T-Cells • Produce lymphokines that inhibit proliferation of B and T cells • Downregulate or dampen immune response

  19. Memory T-Cells • Have previously encountered specific antigens • Respond in enhanced fashion on subsequent exposures • Induce secondary immune response

  20. Inflammation • Occurs in vascularized tissue • Nonspecific response to injury • Response is same regardless of agent that initiates it

  21. Inflammation: Physiology • Triggered by cellular injury • Injury activates mast cells • Mast cells release chemical mediators: • Histamine • Heparin • Leukotrienes (SRS-A) • Eosinophil chemotactic factor

  22. Inflammation: Pathology • Mediators cause: • Vasodilation (redness, heat) • Vascular permeability (swelling) • White cell movement to and infiltration of affected area (pus) • Nerve ending stimulation (pain) “Dolor, Calor, Tumor, Rubor”

  23. Inflammation: Purposes • Confines injurious agents • Increases blood cell, plasma movement to injured areas • Enhances immune response • Destroys injurious agents • Promotes healing

  24. Inflammation: Cellular Components • Neutrophils • Phagocytic cells • Engulf foreign material/organisms • Arrive early • Short-lived

  25. Inflammation: Cellular Components • Macrophages • Phagocytic cells • Engulf foreign material/organisms • Arrive later • Long-lived • Transfer antigens back to T4 cells • Help initiate immune response to specific agents

  26. Inflammation: Cellular Components • Eosinophils • Secrete caustic proteins • Dissolve surface membranes of parasites

  27. Disorders of Immunity

  28. Autoimmune Disease • Clinical disorder produced by an immune response to a normal tissue component of a patient’s body

  29. Autoimmune Diseases • Hyperthyroidism • Primary myxedema • Type I diabetes • Addison’s disease • Multiple sclerosis • Myasthenia gravis

  30. Autoimmune Diseases • Rheumatic fever • Crohn’s disease • Ulcerative colitis • Rheumatoid arthritis • Systemic lupus erythematosis

  31. Systemic Lupus Erythematosis • Primarily occurs in 20- to 40-year old females • Also in children and older adults • 90% of patients are female • Autoimmune reaction to host DNA • Mortality after diagnosis averages 5% per year

  32. Systemic Lupus Erythematosis • Signs/Symptoms • Facial rash/skin rash triggered by sunlight exposure • Oral/nasopharyngeal ulcers • Fever • Arthritis

  33. Systemic Lupus Erythematosis • Signs/Symptoms • Serositis (pleurisy, pericarditis) • Renal injury/failure • CNS involvement with seizures/psychosis • Peripheral vasculitis/gangrene • Hemolytic anemia

  34. Systemic Lupus Erythematosis • Chronic management • Anti-inflammatory drugs • Aspirin • Ibuprofen • Corticosteroids • Avoidance of emotional stress, physical fatigue, excessive sun exposure

  35. Disorders of Immunity Immunodeficiency Diseases

  36. Immunodeficiency Diseases • Congenital • Acquired

  37. Immunodeficiency Diseases: Congenital • B cell deficiency • Agammaglobulinemia • Hypogammaglobulinemia

  38. Immunodeficiency Diseases: Congenital • T cell deficiency • IgA deficiency • Severe combined immune deficiency syndrome (B and T cell deficiency)

  39. Immunodeficiency Diseases: Acquired • Nutritional deficiency • Iatrogenic (drugs, radiation) • Trauma (prolonged hypoperfusion) • Stress • Infection (AIDS)

More Related