The Role of Adenosine in γδ T-Cell Regulation of Th17 Responses in Experimental Autoimmune Uveitis

Autoimmune diseases caused by T cells can arise from either T-helper 1 (Th1) or T-helper 17 (Th17)-type pathogenic T cells. However, it is unclear whether these two T-cell subsets are influenced by distinct pathogenic factors and whether treatments that are effective for Th1 responses also work for Th17 responses. To compare these two pathogenic responses, we conducted a systematic analysis in a mouse model of experimental autoimmune uveitis (EAU) to identify the factors that promote or inhibit each response and to determine their responses to various treatments. Our study found that the two types of pathogenic responses differ significantly in their pathological progressions and susceptibility to treatments. Specifically, we observed that extracellular adenosine is a crucial pathogenic molecule involved in the pathogenicity of inflammation and T-cell reactivity and that reciprocal interaction between adenosine and gamma delta (γδ) T cells plays a significant role in amplifying Th17 responses in the development of autoimmune diseases. The potential effect of targeting adenosine or adenosine receptors is analyzed regarding whether such targeting constitutes an effective approach to modulating both γδ T-cell responses and the pathogenic Th17 responses in autoimmune diseases.