Abstract
Abstract: :
Purpose:Programmed cell death or apoptosis is a process, whereby developmental or environmental stimuli cause cell death, without causing reproliferation or inflammation. Recently we have identified several death receptors in tenon fibroblasts. ( TRAMP, TRAIL, CD95 ) Here we investigated, if the use of topical, glaucoma medication could change the expression of CD95L (Fas/Apo-1 ligand), one of the best known inductors of apoptosis Methods:Expression of CD95L was analyzed in surgically removed tenon tissues by immunohistochemistry. CD95L expression by cultured tenon fibroblasts pretreated with topical glaucoma drugs was assessed by flow cytometry. The general immunostaining procedures were performed as described previously. Surgical specimens were obtained from patients undergoing trabeculectomy for a variety of glaucomatous disorders. All patients gave informed consent prior to surgery. Flow Cytometry: Human Tenon Fibroblasts were treated with Timolol 0,5%, Pilocarpin 1% and Latanoprost 0,005% for 2 weeks on a subtoxic level. Afterwards, flow Cytometry was performed as described previously. The standardized fluorescence index (SFI) was calculated as the ratio of the mean fluorescence values obtained with the specific antibody and the isotype control antibody. Results:CD95L expression could be observed in most specimens. Flow cytometry revealed a marked increase of the CD95 expression for the prostaglandinderivat latanoprost (SFI=9,22) and for the ß-blocker Timoptol (SFI=8,50), in contrast to Pilocarpine-treated cells (SFI= 4,56) and the control (SFI= 4,50). Conclusion:Antiglaucomatous medication has often been shown to alter conjunctival tissue. Since reproliferation of tenon fibroblasts and therefore scarring and closure of filter blebs still is the main reason for failure of glaucoma surgery, induction of apoptosis could lead to a new way of treatment. Here we showed the important fact, that antiglaucomatous medication can alter apoptotic proteins and therefore influence treatments of glaucoma by proapoptotic drugs.
Keywords: 631 wound healing • 323 apoptosis/cell death • 365 conjunctiva