Attenuation of CCl4-Induced Hepatic Fibrosis in Mice by Vaccinating against TGF-β1

Abstract

Transforming growth factor β1 (TGF-β1) is the pivotal pro-fibrogenic cytokine in hepatic fibrosis. Reducing the over-produced expression of TGF-β1 or blocking its signaling pathways is considered to be a promising therapeutic strategy for hepatic fibrosis. In this study, we evaluated the feasibility of attenuating hepatic fibrosis by vaccination against TGF-β1 with TGF-β1 kinoids. Two TGF-β1 kinoid vaccines were prepared by cross-linking TGF-β1-derived polypeptides (TGF-β125–[41-65] and TGF-β130–[83-112]) to keyhole limpet hemocyanin (KLH). Immunization with the two TGF-β1 kinoids efficiently elicited the production of high-levels of TGF-β1-specific antibodies against in BALB/c mice as tested by enzyme-linked immunosorbent assay (ELISA) and Western blotting. The antisera neutralized TGF-β1-induced growth-inhibition on mink lung epithelial cells (Mv1Lu) and attenuated TGF-β1-induced Smad2/3 phosphorylation, α-SMA, collagen type 1 alpha 2 (COL1A2), plasminogen activator inhibitor-1 (PAI-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) expression in the rat hepatic stellate cell (HSC) line, HSC-T6. Vaccination against TGF-β1 with the kinoids significantly suppressed CCl4-induced collagen deposition and the expression of α-SMA and desmin, attenuated hepatocyte apoptosis and accelerated hepatocyte proliferation in BALB/c mice. These results demonstrated that immunization with the TGF-β1 kinoids efficiently attenuated CCl4-induced hepatic fibrosis and liver injury. Our study suggests that vaccination against TGF-β1 might be developed into a feasible therapeutic approach for the treatment of chronic fibrotic liver diseases.

New Developments on the Treatment of Liver Fibrosis

“…Although TGF-β1 is one of the most potent stimuli of extracellular matrix synthesis, suppressing its expression remains a major challenge of antifibrotic therapy, since systemic blocking of TGF-β1 can provoke inflammation and increase the risk of neoplasia. Neutralization of TGF-β in animal models inhibits liver fibrosis and reduces the risk of developing cholangiocarcinoma (14, 15). Fresolimumab (GC1008) is a human anti-TGF-β1 monoclonal antibody that neutralizes all isoforms of TGF-β.…”

New therapies for hepatic fibrosis

“…Although TGF-β1 is one of the most potent stimuli of extracellular matrix synthesis, suppressing its expression remains a major challenge of antifibrotic therapy, since systemic blocking of TGF-β1 can provoke inflammation and increase the risk of neoplasia. Neutralization of TGF-β in animal models inhibits liver fibrosis and reduces the risk in developing cholangiocarcinoma [13][14]. Fresolimumab (GC1008) is a human anti-TGF-β1 monoclonal antibody that neutralizes all isoform of TGF-β.…”

Histological and biochemical studies on the effect of tetrodotoxin extracted from Puffer fish (Lagocephalus sceleratus) against carbon tetrachloride induced hepatotoxicity in albino mice.

“…The present study revealed that intraperitoneal injection with CCl 4 to male albino mice at a dose of 1 ml/kg dissolved in olive oil, twice/week for six weeks following the method of Fan et al (2013) resulted in an increase in the activity of serum ALT and AST. Also, the level of Alb decreased.…”

“…with saline (control group, n=6); 2) mice injected i.p. with CCl 4 (1 ml/kg of body weight, dissolved in olive oil to reach a final concentration of 20%) twice a week for 6 weeks (CCl 4 group, n=6) according to Fan et al (2013); 3) mice administered i.p. 5 doses of TTX extract (1 µg/kg of body weight dissolved in saline) every next day for 10 days (TTX group, n=6); and 4) mice received i.p.…”