Assistant Professor Louisiana State University, Louisiana, United States
Disclosure(s):
Gianluca Veggiani, PhD: No financial relationships to disclose
Introduction/Rationale: Toll-like receptors (TLRs) are central mediators of innate immune signaling, yet their dysregulated activation drives chronic inflammation underlying diseases that affect over 60 million people in the U.S. Current TLR-targeted therapeutics are hindered by poor specificity, limited delivery, and systemic toxicity. To overcome these barriers, we developed a modular peptide-based strategy to selectively inhibit TLR2 and TLR5, two key receptors implicated in sterile and infection-driven inflammation.
Methods: We curated over 5,000 AIP sequences to design a novel phage-display library of 9 billion unique peptides targeting the extracellular domains of TLR2 and TLR5. Lead peptides were validated for binding specificity via phage ELISA. Functional inhibition of TLR signaling was assessed by measuring NF-κB activation. following stimulation with specific TLR agonists. Cytotoxicity and epitope mapping studies were conducted to assess peptide safety and mechanism of action.
Results: We successfully isolated peptides with exquisite specificity for TLR2 or TLR5, demonstrating no cross-reactivity with other TLRs. Epitope mapping confirmed these peptides act as genuine antagonists by competing with natural ligands at their canonical binding sites. In functional assays, they potently suppressed NF-κB activation. Critically, all peptides showed no cytotoxicity, underscoring their potential for safe therapeutic use.
Conclusion: This work establishes a robust platform for discovering selective peptide-based TLR inhibitors. The identified AIPs against TLR2 and TLR5 represent promising, safe therapeutic candidates, highlighting a potent and scalable strategy for controlling pathological inflammation through precise modulation of innate immune pathways.
