Effect of In Vivo Expansion of Regulatory T Cells with IL-2/anti-IL-2 Antibody Complex Plus Rapamycin on Experimental Autoimmune Uveoretinitis

ABSTRACT

Purpose: To determine the effect of injection of IL-2/anti-IL-2 antibody (IL-2 complex) together with rapamycin on the development of experimental autoimmune uveoretinitis (EAU).

Methods: C57BL/6J mice were immunized with human interphotoreceptor retinoid-binding protein peptide. The immunized mice were injected intraperitoneally with PBS, IL-2 complex, rapamycin, or IL-2 complex/rapamycin on days 1, 2, 3, and 4 (induction phase) or days 10, 11, 12, and 13 (effector phase) after immunization.

Results: Expansion of CD4⁺Foxp3⁺ regulatory T cells in draining lymph nodes was observed in IL-2 complex and IL-2 complex/rapamycin-treated mice. Although injection of IL-2 complex alone was not capable of decreasing the clinical score of EAU, injection of IL-2 complex/rapamycin significantly delayed the onset of EAU. In contrast, the treatment with IL-2 complex alone or IL-2 complex/rapamycin during effector phase failed to suppress EAU.

Conclusions: These findings suggest the potential limitations of IL-2 complex or IL-2 complex/rapamycin during EAU.

KEYWORDS:

• Experimental autoimmune uveoretinitis
• Foxp3
• IL-2
• rapamycin
• regulatory T cells

Declaration of interest

The authors have no proprietary or commercial interest in any materials discussed in reporting these observations and this article.

Additional information

Funding

This work was supported by Grant for Research Grant for Young Investigators in Kyorin University, Japan, and Mitsubishi Tanabe Pharma, Japan and by Grant-in-Aid for Scientific Research [26462696] from the Ministry of Education, Culture, Sports, Science, and Technology, Japan.