First Author | Li L | Year | 2014 |
Journal | Nat Chem Biol | Volume | 10 |
Issue | 12 | Pages | 1043-8 |
PubMed ID | 25344812 | Mgi Jnum | J:273512 |
Mgi Id | MGI:6294165 | Doi | 10.1038/nchembio.1661 |
Citation | Li L, et al. (2014) Hydrolysis of 2'3'-cGAMP by ENPP1 and design of nonhydrolyzable analogs. Nat Chem Biol 10(12):1043-8 |
abstractText | Agonists of mouse STING (TMEM173) shrink and even cure solid tumors by activating innate immunity; human STING (hSTING) agonists are needed to test this therapeutic hypothesis in humans. The endogenous STING agonist is 2'3'-cGAMP, a second messenger that signals the presence of cytosolic double-stranded DNA. We report activity-guided partial purification and identification of ecto-nucleotide pyrophosphatase/phosphodiesterase (ENPP1) to be the dominant 2'3'-cGAMP hydrolyzing activity in cultured cells. The hydrolysis activity of ENPP1 was confirmed using recombinant protein and was depleted in tissue extracts and plasma from Enpp1(-/-) mice. We synthesized a hydrolysis-resistant bisphosphothioate analog of 2'3'-cGAMP (2'3'-cG(s)A(s)MP) that has similar affinity for hSTING in vitro and is ten times more potent at inducing IFN-beta secretion from human THP1 monocytes. Studies in mouse Enpp1(-/-) lung fibroblasts indicate that resistance to hydrolysis contributes substantially to its higher potency. 2'3'-cG(s)A(s)MP is therefore improved over natural 2'3'-cGAMP as a model agonist and has potential as a vaccine adjuvant and cancer therapeutic. |