Anti-TNFalpha therapy modulates the phenotype of peripheral blood CD4+ T cells in patients with posterior segment intraocular inflammation

PURPOSE. Posterior segment intraocular inflammation (PSII) is a putative Th1 CD4(+) cell mediated autoimmune disorder. In experimental autoimmune uveoretinitis, neutralization of tumor necrosis factor (TNF)-alpha induces suppression of Th1 cells, macrophage activation, and target organ damage. Previous studies implicated an efficacy of anti-TNFalpha therapies in patients with PSII. This study investigated the immunomodulatory effect of anti-TNFa therapy to find predictors of effective immunosuppression in PSII.

METHODS. Fifteen patients with PSII refractory to conventional immunosuppressive therapy received a single infusion of a recombinant protein generated by fusing the p55 TNFalpha receptor. with human IgG1. During 17 treatment periods, visual acuity (logarithm of the minimum angle of resolution [logMAR]) was monitored as a response criterion. Phenotype markers of CD4(+) T cells were analyzed before and 2, 4, and 12 weeks after therapy. Expression of intracellular cytokines (interferon [IFN]-gamma, interleukin [IL]-10, and TNFa) and Th1/Th2-specific chemokine receptors (CXCR3, CCR4, and CCR5) on peripheral blood CD4(+) T cells was determined using flow cytometry.

RESULTS. The fraction of IL-10 -expressing CD4+ T cells was increased during 12 of 17 treatment periods within 2 weeks after treatment. During eight treatment periods, this increase was associated with an improvement of visual acuity of at least 0.2 logMAR within 4 weeks (P = 0.029). The ratio between IL-10- and IFNgamma- expressing CD4+ T cells was significantly increased 2 weeks after therapy (P = 0.015). There was no significant change of CXCR3, CCR4, or CCR5 expression.

CONCLUSIONS. Neutralizing TNFa activity in PSII increases the fraction of peripheral blood CD4(+) T cells expressing IL-10, which correlates with a recovery of visual function.