Page 413 - Veterinary Immunology, 10th Edition
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VetBooks.ir Th1 Cells
The production of Th1 cells is driven by IL-12 from antigen-
presenting dendritic cells (cDC1), macrophages (M1), and B cells,
plus co-stimulation by CD80. Complete Th1 cell activation,
proliferation, and IFN-γ production is achieved by additional
stimulation by IFN-γ. This signaling activates the transcription
factor T-bet. T-bet is the master regulator of Th1 cell differentiation.
Once activated, Th1 cells produce IL-2, IFN-γ, and TNF-α (Fig.
14.14). Th1 cells promote cell-mediated immune responses such as
the delayed hypersensitivity reaction and macrophage activation.
They thus generate immunity to intracellular organisms such as
mycobacteria and viruses (Fig. 14.15). These “type-1”–associated
cytokines also inhibit type-2 immune responses.
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