Purchase this article with an account.
H. Mietz, G. Welsandt, M. Becker, G.K. Krieglstein; Antiproliferative Effect of Cytotoxic Substances on Conjunctival Fibroblasts: Two Applications of Substances With a Fixed Time Interval . Invest. Ophthalmol. Vis. Sci. 2005;46(13):57.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: The process of wound healing following trabeculectomy involves Tenon and episcleral fibroblasts as target cells. This process is one of the most important factors that distinguish between a surgical success or failure. Current clinical concepts mainly involve antifibroblastic substances given once (Mitomycin) or multiple times (5–Fluorouracil) during or following surgery. To our knowledge, only the antiproliferative effect of a single application on cell proliferation in–vitro has been investigated. In a clinical setting, it may become important to apply such substances more than once to the same eye. For this reason, we aimed to develop an in–vitro model to investigate the cytotoxic effect of two applications of similar and different substances on conjunctival fibroblasts. Methods: 3T3 fibroblasts and human Tenon fibroblasts were cultured. First, Mitomycin and 5–Fluorouracil were applied for 5 minutes. Then, the cells were allowed to grow for 24h. The concentrations used led to a reduction of cell survivial of about 20%. Then, the cells were exposed for another 5 minuntes to Mitomycin, 5–Fluorouracil, Suramin, Lomustin, Doxorubicin and Staurosporin. The cell survival was determined after another 24h using the crystal violet assay. Results: Primary cell proliferation was reliably inhibited with concentrations of 62 µg/ml of Mitomycin and 130 µg/ml of 5–Fluorouracil. Concentrations of the other four substances, which also reduced cell survival by 20% after a single application, only led to a significantly increased cytotoxic effect after the second application with the use of Staurosporin and Doxorubicin (p<0.01 and p<0.05, respectively; t–test). The effect of Suramin and Lomustin was similar to that of a second application of the substance primarily used. Conclusions: The results of this experiment suggest, that the effect of a second application of a cytotoxic substance on conjunctival fibroblasts is largely variable. While the concentrations of all substances were selected to achieve an inhibitory effect of about 20% when applied for the first time, the total inhibitory effect following the second application ranged from 20% to 90%. This finding suggests that only selected substances may be feasible to be used following a primary application of Mitomycin or 5–Fluorouracil.
This PDF is available to Subscribers Only