Calsyntenin-3 suppresses inflammation via inhibition of TLR N-glycosylation and membrane localization.

Summary

Using genome-wide CRISPR screening, the authors identify CLSTN3 as an endogenous brake on TLR-driven inflammation. CLSTN3 disrupts OST complex assembly (via DDOST–STT3A), decreasing N-glycosylation and membrane localization of TLR4 and other TLRs, thereby broadly dampening innate immune activation.

Key Findings

• Genome-wide CRISPR screen identified CLSTN3 as a suppressor of TLR4-triggered inflammation in macrophages.
• CLSTN3 binds DDOST, disrupting its interaction with STT3A, impairing OST complex assembly and TLR4 N-glycosylation.
• Reduced N-glycosylation limits TLR4 membrane translocation; CLSTN3 also suppresses membrane translocation/activation of TLR3, TLR7, and TLR9.

Clinical Implications

By modulating TLR N-glycosylation, CLSTN3 (or its pathway) could inspire therapies that temper hyperinflammation without broad immunosuppression in sepsis and other inflammatory states.

Limitations

• Preclinical mechanistic work; in vivo validation in sepsis models and translational studies are needed
• Safety and specificity of targeting OST assembly require careful evaluation to avoid broad proteostasis effects

Future Directions

Validate CLSTN3-mediated modulation in in vivo sepsis models, assess pharmacologic tractability of the CLSTN3–OST axis, and test whether selective TLR glycosylation tuning improves outcomes without immunoparesis.