Figure 2: The levels of TNF-α after treatment with 1,25(OH)2D3, MTX, and 1,25(OH)2D3 plus MTX in RA patients. The RA patients’ PBMCs treated with either anti-CD3/CD28, or 1,25(OH)2D3, MTX at various concentrations, or the combination of 1,25(OH)2D3 and MTX (D2M2 group). The level of TNF-α was detected and significantly decreased in the groups of 1,25(OH)2D3, MTX and D2M2 compared to the level in the group of anti-CD3/CD28 ( ). *Mean .