Development of a Humanized Anti-Fibrotic Antibody Targeting Extracellular Collagen Assembly to Reduce Post-Traumatic...

Area of Science:

• Biotechnology
• Immunology
• Rheumatology

Background:

• Pathological scarring and fibrosis result from excessive fibrillar collagen accumulation.
• Targeting extracellular collagen assembly offers a promising anti-fibrotic strategy.
• Previous work developed a chimeric antibody disrupting collagen fibrillogenesis by targeting the α2(I) chain of human collagen I.

Purpose of the Study:

• To engineer a humanized antibody variant for therapeutic application against fibrosis.
• To enhance targeted retention in fibrotic tissues using a collagen-binding peptide (CBP).
• To evaluate the efficacy of the engineered antibody in a preclinical model.

Main Methods:

• Humanized antibody (ACA) engineering via in silico modeling, CDR grafting, and sequence optimization.
• Fusion of a CBP to the antibody to improve spatial localization.
• Assessment of in vitro properties (cytotoxicity, matrix retention) and in vivo efficacy in a rabbit arthrofibrosis model.

Main Results:

• Humanized ACA variants retained high specificity and affinity for the α2Ct target.
• CBP fusion (C-cbpACA) enhanced matrix retention without compromising target engagement or causing toxicity.
• Intra-articular C-cbpACA significantly reduced joint contracture and collagen deposition in rabbits.

Conclusions:

• A clinically viable, humanized, matrix-targeted anti-fibrotic antibody was successfully engineered.
• The antibody specifically inhibits extracellular collagen assembly and shows enhanced fibrotic tissue localization.
• This construct is a promising therapeutic for mitigating scarring and improving post-traumatic outcomes.