As we have previously reported that adenosine, generated by the action of CD39 and CD73, plays a critical role in development of both hepatic and dermal fibrosis in murine models of cirrhosis and scleroderma, respectively, [7, 23] we tested the hypothesis that tenofovir’s antifibrotic effects are mediated by inhibition of adenosine production. This evidence concerns the gene ENTPD1 and scleroderma.