Chapter 27 Immunologic Diseases

1. Chapter 27 Immunologic Diseases

2. Review of Structure and Function • Immunity means the resistance to, or protection from an individuals environment. • As simple as that sounds, there are multiple ways this is achieved.

3. Immunity • Innate immunity • Skin • Inflammatory responses • Adaptive immunity • Internal chemical reaction to foreign substances (antigens) in the body

4. Incomplete and Complete Antigens • Incomplete Antigens (Haptens) • These cannot trigger an immune response unless coupled with another antigen. • Complete antigens • These can induce an immune response and also interact with the antibodies produced by an immune response.

5. T cells and B cells • B lymphocytes are capable of developing into plasma cells to produce immunoglobins. • They originate from the lymphoid tissue of the GI tract and bone marrow

6. T cells and B cells • T lymphocytes are produced by the thymus, and are broken down further • T-helper Cells • T-suppressor Cells • Cytotoxic T cells

7. T cells • Antigens are broken down and presented to T cells. • When this occurs, the body will stimulate B cells to create antibodies (T-helper cells), suppress the production of antibodies (T-suppressor cells), or direct kill the foreign cell (Cytotoxic T-cell)

8. Immunoglobins • IgG • Most abundant, very active in bacterial infections • IgM • Controls bacteria and clumping of large foreign substances • IgA • Secreted in bodily fluids

9. Immunoglobins • IgE • Histamine release in the allergic response • IgD • Antigen receptor on the surface of mature B cells

10. Classification of Immunologic Diseases • Immune deficiency disease • Too little response to foreign agents • T-cell or B-cell deficiencies • Hypersensitivity reactions • Too much response to antigens • Types I-IV

11. Hypersensitivity Responses • Type I • Anaphylactic-atopic allergy • Type II • Cytotoxic-type hypersensitivity

12. Hypersensitivity Responses • Type III • Immune complex or Arthus-type • Type IV • Delayed hypersensitivity

13. Most Frequent Type I Hypersensitivities • Allergic rhinitis • This is considered a chronic reaction • Allergic asthma • This is also considered a chronic reaction with acute episodes as well

14. Most Frequent Type I Hypersensitivities • Anaphylactic reactions • This is an acute reaction

15. Common Type II, III, and IV Hypersensitivities • Type II (Cytotoxic) • Transfusion reactions • Erythroblastosisfetalis • Type III (Immune complex) • Serum sickness • Cryoglobulinemia

16. Common Type II, III, and IV Hypersensitivities • Type IV (Delayed) • Allergic contact dermatitis • Poison Ivy

17. Diagnosis • Type I • Allergy skin testing • Type II • Direct Coombs test

18. Diagnosis • Type III • Immunofluorescence • Type IV • Injection under the skin, or a skin patch test.

19. Immune Deficiency Diseases • Primarily manifested by an increased susceptibility to infections. • B-cell system deficiency • Pyogenic pneumonia • T-cell system deficiency • Absence of skin reactivity

20. Autoimmune Diseases • Systemic Lupus Erythematosus (SLE) • A relatively common auto-immune disease • Usually affects multiple organ systems