Page 292 - Veterinary Immunology, 10th Edition

endothelial cells, fibroblasts, NK cells, smooth muscle cells,
VetBooks.ir astrocytes, microglial cells, platelets, and some epithelial cells such

as thymic epithelial cells and corneal cells. Their effectiveness may
depend on the local environment. Thus fibroblasts may be very

effective antigen-processing cells when located within granulomas.
Presumably, costimulation can come from other nearby cells in this
cytokine-rich environment. Vascular endothelial cells can also take
up antigens, synthesize IL-1, and under the influence of IFN-γ,

express MHC class II molecules. Even skin keratinocytes can secrete
cytokines similar to IL-1, express MHC class II molecules, and
present antigen to T cells. In pigs, a subpopulation of circulating γ/δ
T cells may act as professional antigen-processing cells.

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