Monoclonal antibodies anti-TGFβ1 and anti-VEGF inhibit the experimental pleurodesis induced by silver nitrate

Abstract

Background. The mechanisms underlying pleural inflammation and pleurodesis are poorly understood. We hypothesized that the cytokines transforming growth factor β (TGFβ1) and vascular endothelial growth factor (VEGF) play a major role in pleurodesis after intrapleural silver nitrate (SN) injection. Method. Forty rabbits received intrapleurally 0.5% SN alone or 0.5% SN + anti-TGFβ1, anti-IL-8, or anti-VEGF. After 28 days, the animals were euthanized and macroscopic pleural adhesions, microscopic pleural fibrosis, and collagen deposition were analyzed for characterization of the degree of pleurodesis (scores 0–4). Results. Scores of pleural adhesions, pleural fibrosis, total collagen, and thin collagen fibers deposition after 28 days were significantly lower for 0.5% SN + anti-TGFβ1 and 0.5% SN + anti-VEGF. Significant correlations were found between macroscopic adhesion and microscopic pleural fibrosis with total collagen and thin collagen fibers. Conclusions. We conclude that both TGFβ1 and VEGF, but not IL-8, mediate the pleural inflammatory response and pleurodesis induced by SN.

Keywords::

• Pleura
• pleurodesis
• cytokines
• inflammatory mediators

Declaration of interest: The authors of this manuscript have no conflicts of interest or any personal/financial support or involvement with organization(s) with financial interest in the subject matter. Foundation to Support Research was from the State of Sao Paulo (FAPESP), Brazil. The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.