Li-Fong Seet, Li Zhen Toh, Stephanie Chu, Sharon N. Finger, Florent Ginhoux, Wanjin Hong, Tina T. Wong; Bevacizumab Promotes T-Cell–Mediated Collagen Deposition in the Mouse Model of Conjunctival Scarring. Invest. Ophthalmol. Vis. Sci. 2018;59(3):1682-1692. doi: https://doi.org/10.1167/iovs.17-22694.
Abstract:
Purpose: We determine the effects of bevacizumab on collagen production in a mouse model of conjunctival scarring.
Methods: Experimental surgery was performed as described for the mouse model of conjunctival scarring, and bevacizumab was introduced by conjunctival injection. The capacity of bevacizumab to recognize conjunctival VEGF-A was determined by ELISA. Col1a1 was measured by real-time PCR and immunoblotting. T cells and collagen were visualized by immunofluorescence and picrosirius red staining of bleb cryosections. Conjunctival CD4+ or CD8a+ T cells were counted by flow cytometry. Mouse splenic T cells were cultured with bevacizumab/IgG and their numbers, cell cycle, and collagen production were measured using a cell counter, flow cytometry, and sircol soluble collagen assay, respectively. Reconstitution experiments in severe combined immunodeficiency (SCID) mice were performed by injection of freshly isolated T cells on day 2 postoperatively.
Results: Bevacizumab recognized approximately 20% of endogenous murine VEGF-A. Injection of bevacizumab raised Col1a1 expression in the blebs at mRNA and protein levels. Bevacizumab did not induce collagen in conjunctival fibroblasts, but increased CD4+ and CD8a+ cell numbers as well as collagen production by these cells. Collagen appeared to accumulate in the vicinity of T cells in the bevacizumab-treated blebs. While SCID blebs did not show elevated collagen levels, reconstitution with CD4+ or CD8a+ cells resulted in increased Col1a1 expression at mRNA and protein levels.
Conclusions: Bevacizumab increased collagen production in the mouse model of conjunctival scarring. This collagen induction was mediated by T cells that were also stimulated by bevacizumab to increase in numbers.
License type:
http://creativecommons.org/licenses/by-nc-nd/4.0/
Funding Info:
Supported by the Singapore National Research Foundation under its Translational and Clinical Research (TCR) Programme (NMRC/TCR/002-SERI/2008) administered by the Singapore Ministry of Health's National Medical Research Council. Animal studies were partially funded by the SERI core grant (NMRC/CG/015/2013).
Description:
This is a version of record published in Investigative Ophthalmology & Visual Science. The final authenticated version is available online at: https://doi.org/10.1167/iovs.17-22694