Page 957 - Veterinary Immunology, 10th Edition

plays an important role in resistance to parasitic helminths and
VetBooks.ir arthropods. It is also, however, a cause of unwanted inflammatory

disease and thus of major significance in veterinary medicine. IgE
production is characteristic of type 2 responses. These responses are

triggered by the production of interleukin-4 (IL-4) and other
cytokines from Th2 cells.

FIG. 29.1 The mechanism of type I hypersensitivity reactions.
Numerous biologically active molecules and inflammatory mediators
are released by mast cells when antigen cross-links two IgE
molecules on the mast cell surface. Some are produced
immediately. Others may be synthesized within minutes or hours.

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