A Dual-Domain Peptide Strategy for Targeted Regenerative Repair

Objectives This project aims to develop and evaluate a modular synthetic peptide designed to enhance tissue regeneration through coordinated extracellular matrix targeting and immune modulation. The peptide construct incorporates a collagen-binding domain (CBD) to spatially localize bioactivity within matrix-rich tissues. Two alternative CBDs are investigated: a DMP1-derived acidic motif (CBD1: DSESSEEDR) and a collagen-interactive sequence derived from a collagenase-associated domain (CBD2: TKKTLRT), enabling tunable collagen affinity and sustained local retention. This matrix-targeting module is coupled to an anti-inflammatory kinase inhibitory region derived from suppressor of cytokine signaling 1 (SOCS1; KIR), fused to a TAT cell-penetrating peptide (KIR-TAT) to promote intracellular delivery and attenuation of pro-inflammatory signaling pathways. Collectively, this dual-domain design seeks to confine therapeutic activity to the target tissue while modulating inflammation, thereby establishing a microenvironment favorable for regenerative repair. Methods To validate the functionality of the dual-domain peptide platform, both extracellular matrix targeting and intracellular anti-inflammatory activity were systematically evaluated. Collagen-binding performance of CBD1 and CBD2 was assessed using collagen-coated substrates, with quantitative analysis of binding affinity, matrix retention, and peptide release kinetics. Controlled release studies were conducted to characterize peptide dissociation profiles from collagen surfaces over time. The immunomodulatory module, consisting of SOCS1-derived KIR fused to a TAT cell-penetrating peptide, was evaluated for cellular uptake and biological activity. Intracellular delivery was visualized using confocal microscopy, while anti-inflammatory efficacy was quantified by qPCR analysis of pro-inflammatory gene expression. Together, these studies establish the structure–function relationships of each peptide component and assess their combined performance in creating a regenerative microenvironment. Results The results demonstrate effective and complementary functionality of the two modular components of the synthetic peptide platform. Comparative collagen-binding assays showed that CBD2 (TKKTLRT) exhibited significantly stronger and more sustained binding to collagen-coated surfaces than the DMP1-derived CBD1 (DSESSEEDR). This enhanced binding translated to improved matrix retention and slower peptide release kinetics, indicating superior suitability of CBD2 for applications requiring prolonged local bioactivity. In parallel, cellular studies confirmed that the KIR-TAT module functioned as intended, exhibiting efficient intracellular delivery as observed by confocal microscopy and robust suppression of pro-inflammatory gene expression as measured by qPCR. These findings validate the dual-domain design strategy by demonstrating enhanced matrix anchoring via CBD2 and effective intracellular immune modulation via KIR-TAT. Conclusions This study establishes the feasibility of a modular dual-domain peptide approach for regenerative applications. CBD2 provides superior collagen binding and sustained matrix retention compared to CBD1, while the KIR-TAT module effectively mediates intracellular anti-inflammatory signaling. Together, these results support a rational peptide design strategy that integrates extracellular matrix targeting with immune modulation to create a localized, pro-regenerative microenvironment.

Author dc:creator

• Li-Wei Teng (2272204)

• Development of Functionalized Collagen-Chitosan Hydrogels Incorporating CBD
• KIR
• and TAT Peptides for Anti-Inflammatory Applications.

Statement dc:rights

• In Copyright
• Open Access after 2028-05-01

DOI dc:identifier

https://doi.org/10.25417/uic.32995052.v1

OAI identifier oai:identifier

oai:figshare.com:article/32995052