Blocking peptides are synthetic or recombinant peptides engineered to interfere with protein-protein interactions (PPIs) by competitively binding to target proteins. Their design often mimics regions of interacting proteins (e.g., receptor-binding domains or enzyme active sites). Applications range from basic research (e.g., validating PPI roles) to therapeutic interventions. 

Mechanisms of Action

Blocking peptides function through several mechanisms:

• Competitive Inhibition: Blocking peptides bind to target proteins (e.g., cytokines, receptors) with high affinity, preventing endogenous ligand interactions. For example, the IL-1 receptor antagonist peptide blocks IL-1β signaling, mitigating inflammation.
• Allosteric Modulation: Some peptides disrupt PPIs indirectly by binding to allosteric sites, altering protein conformation.

Therapeutic and Research Applications

Blocking peptides have diverse applications in both research and therapy:

• Autoimmune Diseases: Peptides blocking MHC class II-T cell receptor interactions (e.g., glatiramer acetate) reduce relapse rates in multiple sclerosis.
• Cancer: Peptides targeting PD-1/PD-L1 interactions (e.g., AUNP-12) enhance antitumor immunity but face delivery challenges.
• Inflammation: Blocking the HMGB1-TLR4 interaction with synthetic peptides attenuates sepsis-induced organ damage.

Blocking peptides hold immense potential for modulating PPIs in disease contexts. We provide researchers and clinicians with blocking peptides and delivery solutions designed to overcome the limitations discussed in this review. Our products are rigorously validated for specificity, stability, and efficacy, empowering your work in PPI research and therapeutic development.