Targeting protein-protein interaction for immunomodulation: A sunflower trypsin inhibitor analog peptidomimetic...

Area of Science:

• Immunology
• Drug Discovery
• Biochemistry

Background:

• Protein-protein interactions (PPI) involving co-stimulatory molecules CD2-CD58 are crucial for initiating immune responses.
• Elevated CD2-CD58 expression is noted in the synovium of rheumatoid arthritis (RA) patients, suggesting their role in the disease pathogenesis.

Purpose of the Study:

• To design and synthesize a novel peptidomimetic capable of inhibiting CD2-CD58 PPI.
• To evaluate the in vitro and in vivo efficacy and stability of the designed peptidomimetic for potential therapeutic applications in autoimmune diseases.

Main Methods:

• Grafting of a CD2 epitope that binds CD58 onto the sunflower trypsin inhibitor (SFTI) peptide template.
• Incorporation of a dibenzofuran (DBF) organic moiety into the peptidomimetic structure.
• In vitro assessment of CD2-CD58 interaction inhibition, thermal stability, and enzymatic stability (trypsin cleavage).
• In vivo evaluation using a collagen-induced arthritis (CIA) mouse model.

Main Results:

• The designed peptidomimetic demonstrated stability against trypsin cleavage.
• In vitro studies confirmed the inhibition of CD2-CD58 interactions.
• In vivo studies in the CIA mouse model showed that the peptidomimetic could slow the progression of arthritis.

Conclusions:

• Grafting organic functional groups onto the stable SFTI peptide template enhances structural stability.
• This approach provides a viable strategy for designing stable peptide-based therapeutics for autoimmune diseases.
• The developed peptidomimetic shows promise as a potential treatment for rheumatoid arthritis.