Page 1370 - Veterinary Immunology, 10th Edition

NF-κB moves to the nucleus and activates genes involved in
VetBooks.ir inflammation and immunity. However, because corticosteroids

stimulate the production of IκBα, it continues to block NF-κB–
mediated processes, including cytokine synthesis and T cell

responses. As a result, corticosteroids suppress both immunological
and inflammatory processes.

FIG. 41.1 A schematic diagram showing the mode of action of
corticosteroids. Normally, signal transduction and cytokine
synthesis occur when the transcription factor NF-κB dissociates
from its inhibitor IκBα. The released IκBα is rapidly degraded.
Corticosteroids stimulate the synthesis of excessive amounts of
IκBα that binds to NF-κB and continues to prevent its activation.

Corticosteroids influence immunity in four areas (Box 41.1): they

affect leukocyte production and circulation; they influence the
effector mechanisms of lymphocytes; they modulate the activities of

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