Tumor necrosis factor-α blockade treatment decreased CD154 (CD40-ligand) expression in rheumatoid arthritis

Contexts CD154 (commonly referred to as CD40-ligand) is a critical T cell factor that participates in the pathogenesis of autoimmune and is over-expressed in rheumatoid arthritis (RA). TNF-alpha blockade treatment had dramatic efficacy in RA. Objective To investigate whether TNF-alpha blockade treatment can inhibit CD154 expression in RA. Methods Blood samples were collected from 33 patients with rheumatoid arthritis before and 3 months after TNF-alpha blockade treatment. Clinical serological data determined by standard assays and T cell CD154 expression levels determined by flow cytometry were statistically analyzed for these two time points. Results The percentage of CD154 expression on gated CD4+ T cells of PBMCs from RA patients after 3 months TNF-alpha blockade treatment was significantly lower than before treatment (2.94 +/- 3.21% vs. 7.21 +/- 5.64%; p = 0.0001). The disease activity and anti-CCP antibody levels were also significantly reduced after TNF-alpha blockade treatment. The CD154 expression levels were positively correlated with disease activity index DAS28, and CRP. The post-stimulated CD154 expression percentage of purified CD4+ T cells between baseline and after TNF-alpha blockade treatment was not significantly different (p = 0.221). Baseline CD154 levels were positively correlated with treatment-induced changes in DAS28 (p = 0.014; r2 = 0.187). Conclusions TNF-alpha blockade treatment significantly decreased the CD154 expression on CD4+ T cells, disease activity and anti-CCP antibody simultaneously in RA patients. However TNF-alpha blockade did not impair T cell capacity to express CD154 after stimulation. These results suggest that decreased CD154 expression after TNF-alpha blockade may be due to decreased RA disease activity but not direct inhibition of CD154 responsiveness of T cells.