Identification and Characterization of a Novel Nanobody Against Human CTGF to Reveal Its Antifibrotic Effect in an in vitro Model of Liver Fibrosis

Abstract

Background No agents are currently available for the treatment or reversal of liver fibrosis. Novel antifibrotic therapies for chronic liver diseases are thus urgently needed. Connective tissue growth factor (CTGF) has been shown to contributes profoundly to liver fibrogenesis, which makes CTGF as a promising target for developing antifibrotic agents. Methods In this study, we identified a novel nanobody (Nb) against human CTGF (anti-CTGF Nb) by phage display using an immunized camel, which showed high affinity and specificity in vitro. LX-2 cells, the immortalized human hepatic stellate cells, were induced by transforming growth factor beta1 (TGFβ1) as an in vitro model of liver fibrosis to verify the antifibrotic activity of the anti-CTGF Nb. Results Our data demonstrated that anti-CTGF Nb effectively alleviated TGFβ1-induced LX-2 cell proliferation, activation, and migration, and promoted the apoptosis of activated LX-2 cells in response to TGFβ1. Moreover, the anti-CTGF Nb remarkably reduced the levels of TGFβ1, Smad2, and Smad3 expression in LX-2 stellate cells stimulated by TGFβ1. Conclusion Taken together, we successfully identified a novel Nb against human CTGF, which exhibited antifibrotic effects in vitro by regulating the biological functions of human stellate cells LX-2.

Therapeutic Potential and Mechanisms of Rosmarinic Acid and the Extracts of Lamiaceae Plants for the Treatment of Fibrosis of Various Organs

“…CTGF regulates the proliferation and differentiation of cells, as well as other biological processes, and participates in the development of inflammation, fibrosis, cancer, and other diseases [38]. Therefore, CTGF is a promising therapeutic target to treat various fibrotic diseases [39,40]. A specific monoclonal antibody (FG-3019) against CTGF recovered the impaired lung function in mice exposed to radiation, improved the reduced grip strength in rats induced by chronic overuse of the upper extremity skeletal muscle, and prevented fibrosis in both animal models [40,41].…”