Inhibition of COX-1/COX-2 and iNOS synergistically enhances OT-II CD4⁺ T cell proliferation and IFN-γ production <i>in vitro</i>.

<p>(A) CFSE-stained OT-II CD4⁺ T cells were mixed with congenic DCs and stimulated with OVA protein with or without TLR agonists in combination with L-NMMA (40 μM) or Indo (10 μM) for 4 days. Proliferation of OT-II CD4⁺ T cells were analyzed by CFSE dilution. The range and number in each plot indicate cells that proliferated at least one time. Data shown are representative of two independent experiments. (B) OT-II CD4⁺ T cells were mixed with congenic DCs and stimulated with OVA protein with or without TLR agonists and inhibitors for 4 days. GolgiPlug was added to the cultures to inhibit exocytosis of intracellular IFN-γ at 5 h before harvest. Cells were first stained for CD4, fixed, and stained for intracellular IFN-γ. The numbers in the upper right quadrant signifies the percentage of IFN-γ positive cells among CD4⁺ T cells. Dead cells were excluded using a fixable live/dead dye. Data shown are representative of two independent experiments. iNOS: inducible nitric oxide synthase; COX: cyclooxygenase.