1 / 19

Chapter 15 Hypersensitivity Reactions

Chapter 15 Hypersensitivity Reactions. Mast cell. Although the word “ hypersensitivity ” implies an increased response, the immune response of a hypersensitivity reaction is not necessarily heightened but instead, an inappropriate response to an antigen. Portier and Richet :

lawson
Download Presentation

Chapter 15 Hypersensitivity Reactions

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. Chapter 15 Hypersensitivity Reactions Mast cell

  2. Although the word “hypersensitivity”implies an increased response, the immune response of a hypersensitivity reaction is not necessarily heightened but instead, an inappropriate response to an antigen.

  3. Portier and Richet : Anaphylaxis 過敏反應 ↕ Prophylaxis 預防 Richet was awarded the Nobel Prize in 1913 for the discovery of anaphylaxis. Portuguese man-of-war

  4. Four Types of Hypersensitive Responses Immediate Hypersensitivity: Type I IgE-mediated hypersensitivity Type II IgG- or IgM-mediated cytotoxic hypersensitivity Type III Immune complex-mediated hypersensitivity Delayed-type Hypersensitivity: Type IV Cell-mediated hypersensitivity

  5. Type I Hypersensitivity - IgE-mediated hypersensitivity

  6. allergen (過敏原), allergic (過敏的) atopy (過敏體質), atopic (具有過敏體質的)

  7. Transfusion Reactions are Type II Reactions

  8. Hemolytic Disease of the New Born is Caused by Type II Reactions

  9. Type III Hypersensitivity Localized Type III Reaction - Arthus Reaction tissue damage

  10. Generalized Type III Reaction – Serum Sickness fever, weakness, rashes, edema, erythema, arthritis, glomerulonephritis

  11. Type IV Hypersensitivity Some populations of activated TH cells encounter certain types of antigens, they secrete cytokines that induce a localized inflammatory reaction called delayed-type hypersensitivity (DTH). The term “hypersensitivity” is misleading, since it suggests that a DTH response is detrimental. Although a DTH response can cause extensive tissue damage in some cases, DTH plays an important role in defense against intracellular pathogens .

  12. Granuloma Formation - Caused by a prolonged DTH response

  13. Contact Dermatitis Is A Type of DTH formaldehype, trinitrophenol, nickel, turpentine, detergents, poison ivy, poison oak, and active agents in various cosmetics and hair dyes

  14. Summary

More Related