Revving up cGAS

Cytosolic DNA is a well-known trigger of innate immunity, but it was only last year that its primary sensor, cyclic GMP-AMP synthase, was identified.¹ Now, the first in vivo functional study of the protein has confirmed its essential role in antiviral immunity and strengthened the case for developing modulators of cyclic GMP-AMP signaling, including agonists that serve as adjuvants or inhibitors for autoimmune conditions.²

A core component of the innate immune response is its ability to detect and react to foreign molecules, including DNA or RNA, during viral or bacterial infections. The toll-like receptors (TLRs), which are localized to the cell surface and in endosomes, are the best-understood system for this recognition. For example, foreign DNA is detected by TLR9, which recognizes unmethylated CpG sites commonly found in bacterial and viral DNA...