2’2’-cGAMP

STING ligand

2’2’-cGAMP, cyclic [G(2’,5’)pA(2’,5’)p], is a synthetic cyclic di-nucleotide that binds STING (stimulator of IFN genes) and subsequently induces TBK1-IRF3-dependent production of IFN-β [1]. 2’2’-cGAMP is the isomer of cGAMP most similar to 2’3’-cGAMP in terms of STING binding and type I interferon induction [1].

Certain variants of STING are able to distinguish between noncanonical and canonical cGAMP [2]. cGAMP is more potent in activating type I IFN than c-di-IMP, c-di-AMP and c-diGMP, other cyclic dinucleotides that also bind STING [3].

1. Zhang X. et al., 2013. Cyclic GMP-AMP containing mixed phosphdiester linkages is an endogenous high-affinity ligand for STING. Mol Cell.51(2):226-35.
2. Diner E. et al., 2013. The Innate Immune DNA Sensor cGAS Produces a Noncanonical Cyclic Dinucleotide that Activates Human STING. Cell Rep. 3(5):1355-61.
3. Burdette D. et al., 2011. STING is a direct innate immune sensor of cyclic di-GMP. Nature. 478(7370):515-8.

THP1-Dual™ cells were stimulated for 24 hours with the STING ligands as shown (all at 10 μg/ml). IRF induction was determined by measuring the relative light units (RLUs) in a luminometer using QUANTI‑Luc™, a Lucia luciferase detection reagent.

THP1-Dual™ cells were stimulated for 24 hours with the STING ligands as shown (all at 10 μg/ml). NF‑kB induction was determined using QUANTI‑Blue™, a SEAP detection reagent, and by reading the optical density (OD) at 655 nm. Non-induced cells (NI) have been included as a negative control.

Specifications

Description: Synthetic STING agonist
Synonym: Cyclic [G(2’,5’)pA(2’,5’)p], cyclic GMP-AMP; c-GpAp sodium salt
Formula: C₂₀H₂₂N₁₀O₁₃P₂ .2Na
Molecular weight: 718.38
Purity: ≥ 95% by LC/MS
Solubility: 50 mg/ml in water

Quality control:
- The biological activity is assessed by measuring induction of the interferon pathway in THP1-Blue™ ISG cells.
- The absence of endotoxins and other bacterial contaminants has been confirmed using HEK-Blue™ TLR4 and HEK-Blue™ TLR2 cells.

Contents

2’2’-cGAMP is provided as a lyophilized powder and is available in two quantities:
- 500 µg 2’2’-cGAMP
- 1.5 ml endotoxin-free water

or

- 1 mg (2 x 500 µg) 2’2’-cGAMP
- 1.5 ml endotoxin-free water

2’2’-cGAMP is shipped at room temperature and should be stored at -20°C. Product is sterile filtered prior to lyophilization.