|
|
 |
 |
104. Jahrestagung der Deutschen Ophthalmologischen Gesellschaft 2006
Abstract
Abstract
FR.17.08 HP-Guar as a new tear substitute  An in vitro toxicity study Kasper K.1, Kremling C.1, Geerling G.2
1University of Luebeck, Department of Ophthalmology, Luebeck, 2University Hospital Wuerzburg, Eye Hospital, Wuerzburg Objective: The use of preservatives in pharmaceutical tear substitutes induces cytotoxic effects. HP-Guar has been introduced recently as a new artificial tear substitute. To reduce toxicity it is preserved with polyquad (0.001%), which is considered to be not toxic. We therefore examined the effect of preserved and unpreserved HP-Guar in dose- and time-response experiments in a human corneal epithelial cell culture model.
Methods: SV-40 immortalised human conjunctival and corneal epithelial cells were cultured in 96-well plates at 37°C, 5% CO2. Cell migration was assessed in a colony dispersion assay, proliferation quantified by means of a luminescence-based ATP-assay and cytotoxicity was visualised with a double fluorescent viability staining (Calcein AM/Ethidium-homodimerD-1). All experiments were performed in triplicates and repeated at least once. The significance of differences in cell proliferation was determined with an unpaired two-sided t test.
Results: HPMC with preservative was severely cytotoxic at all concentrations tested. Unpreserved HPMC however showed an inhibition of proliferation only at 100% and no toxicity in the fluorescent viability. HP-Guar with and without preservative were found to be more toxic than unpreserved HPMC, but the unpreserved solution was found to reduce cellular ATP levels and to permeabilise cell membranes significantly more than the preserved solution.
Conclusions: As expected unpreserved HPMC was found to be significantly less cytotoxic than the preserved solution. Paradoxcially HP-Guar without polyquad was found to be more toxic than the unpreserved solution. Possible explanations and limitations of the test model are discussed.
Zurück | Back
|
