Chapter 9 - Autoimmune diseases and the role of Toll-like receptor-7 and -9 signaling cascades

Abstract

Endosomal toll-like receptors such as TLR7 and TLR9 are often upregulated in autoimmune settings. Interestingly, studies in animal models have largely confirmed a dichotomous function of these two receptors, with TLR7 being pathogenic and TLR9 being protective. We here introduce these TLRs and discuss data supporting a role for each in five different autoimmune disorders based on both human and animal data. Furthermore, we present a comprehensive list of currently known agonists and antagonists of TLR7 and TLR9 activation and signaling, speculating on the potential use of these therapeutics in autoimmunity.