FIGURE 6.

Concomitant treatment of MTX with an anti-TNF agent enhanced apoptosis of activated human CD4⁺ T cells. (A) CD4⁺ T cells were cultivated in the 96-well plate and activated by anti-CD3/28 Ab for 1 h. And then, cells were stimulated with 5 μg/ml PHA for 48 h. Cells were stained with FITC-conjugated anti-TNF and expression levels of TNF on the cells surface was detected by flow cytometry. (B) CD4⁺ T cells were untreated (Ctrl) or treated with PHA and stimulated with 1 μM MTX, 1 μM IFX, or combination of MTX and IFX for 48 h. The stimulated cells were stained with FITC-conjugated Annexin V and PI, and the apoptotic cells were detected by flow cytometry. (C,D) Similar experiments were performed with ETN (C) or CZP (D) instead of IFX. Values are mean ± SEM; n = 5/group, *p < 0.05, **p < 0.01, Paired t-test.