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Purpose: To assess the effect of alkylphosphocholine (APC)-coated intraocular lenses (IOLs) on human lens epithelial cell (LEC) proliferation in vitro and the corneal biocompatibility of APC in an organ culture model of human donor eyes., Setting: Research Laboratory for Experimental Ophthalmology, Ludwig-Maximilians-University, Munich, Germany., Design: Experimental study., Methods: Six foldable IOLs differing in optic material were incubated with APC, washed in phosphate-buffered saline, and dried overnight. Intraocular lenses of the same lot served as uncoated controls. Each rehydrated IOL was placed in 1 well of a 24-well plate containing proliferating human LECs. Cell survival was tested by the tetrazolium-dye reduction assay 5 days later. Biocompatibility of the human corneal endothelium was assessed by a 24-hour incubation of human donor corneas with different concentrations of APC before the live/dead assay was performed., Results: Human LEC proliferation was attenuated by APC-coated IOLs (P=.001). Coated hydrophilic acrylic IOLs were more effective inhibitors of human LEC proliferation than coated hydrophobic acrylic or silicone IOLs (P=.001). Alkylphosphocholines were well tolerated by the corneal endothelium in an organ culture model of human donor corneas up to a concentration of 1 mM (n = 12)., Conclusions: Results show that APCs are suitable agents for IOL coating without linker molecules. Coated IOLs can inhibit human LEC proliferation and were well tolerated by human donor corneas in organ culture., (Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the effect of alkylphosphocholines (APCs) on human lens epithelial cell (LEC) proliferation, attachment, and migration in a well-established in vitro model., Setting: Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany., Methods: The immortalized human LEC line HLE-B3 was incubated for 24 hours with APC in different concentrations in the presence of Eagle's modified essential medium supplemented with fetal calf serum under standard cell-culture conditions. The trypan blue exclusion test and live-dead assay were performed to exclude toxic concentrations. To determine cell proliferation, cells were incubated with APCs at the maximum slope of the growth curve for 24 hours before the tetrazolium dye-reduction assay (MTT test) was performed. After cells were seeded on coated 24-well plates, incubated with APCs, and rinsed with phosphate-buffered saline, cell attachment was assessed by the MTT test. Migration was determined by a modified Boyden chamber method after incubation of LECs with APCs., Results: Alkylphosphocholines were effective inhibitors of human LEC proliferation, attachment, and migration at nontoxic concentrations in vitro. The 50% inhibitory concentration was close to 0.1 mM. An APC concentration of 1.0 mM accounted for the following: inhibition of cell proliferation of more than 80%, reduction in cell attachment to 66.5%, and inhibition of cell migration of more than 90%. All effects were dose dependent. No toxic effects were detected compared with controls., Conclusions: Alkylphosphocholines might have the potential for topical application as a single-dose agent to prevent posterior capsule opacification formation. However, further studies are needed before a clinical application can be considered.

Proliferative vitreoretinopathy represents the major complication in retinal detachment surgery and occurs in about 5-15% of cases resulting in a significant loss of vision despite multiple surgical procedures. Although successful anatomical reattachment is usually achieved, the reduction in central vision often remains permanent due to the intraretinal changes induced by retinal detachment and the subsequent proliferative response within the retina. Retinal Muller glial cells play a pivotal role in this process together with retinal pigment epithelial cells which are dispersed in the vitreous and stimulated by growth factors and serum in the vitreous after the breakdown of the blood-retinal barrier., (Copyright 2009 S. Karger AG, Basel.)

Purpose: Alkylphosphocholines (APCs) are investigated for their effect on Müller glial cell proliferation and F-actin stress fiber distribution in vitro., Materials and Methods: Müller cells were incubated with APCs (C18:1-PC and C22:1-PC) +/- fetal calf serum. Proliferation was assessed by BrdU labeling and with the tetrazolium dye-reduction assay. Toxicity was measured using the trypan blue exclusion assay. The distribution of F-actin stress fibers was determined using FITC-phalloidin staining., Results: APCs are effective inhibitors of human and rat Müller glial cell proliferation and hypoxia-induced up-regulation of F-actin stress fibers in vitro in non-toxic concentrations., Conclusions: APCs might prevent intraretinal changes as a result of serum stimulation and hypoxia following retinal detachment.

Purpose: To determine the effect of alkylphosphocholines (APCs) on intraretinal proliferation induced by experimental retinal detachment in the rabbit., Methods: Retinal detachments were created in adult pigmented rabbits. APCs, either liposome bound (liposome, L-APC) or unbound (free, F-APC), were injected intravitreally on either day 1 or day 2 after detachment. BrdU was injected on day 3, 4 hours before death. After fixation, retinas were triple labeled with anti-BrdU, anti-vimentin, and the isolectin B4. The number of anti-BrdU-labeled cells was counted per millimeter of retina from sections imaged by laser scanning confocal microscopy. Toxicity was examined using toluidine blue-stained sections imaged by light microscopy and by electron microscopy for ultrastructural evaluation., Results: Retinal detachment initiated proliferation of all non-neuronal cells. After intravitreal injection on day 1 or 2 after experimental induction of retinal detachment, APCs significantly reduced the number of dividing cells at day 3. Liposome-bound drug given on day 2 was more effective on Müller cell proliferation than was unbound drug. Injection of F-APC on day 1 was more effective than when given on day 2. No apparent effect was seen on Müller cell hypertrophy as indicated by vimentin expression. In addition, no evidence of toxicity was observed in the retina at day 3 for any of the conditions., Conclusions: APCs significantly reduce the number of Müller cells that are stimulated to divide as a result of retinal detachment. The preliminary results indicate no evidence of significant toxicity; however, further studies are needed. APCs have the potential to be used as part of a therapeutic approach if they can be combined with other agents that can suppress the fibrosis that is also a critical event in the pathogenesis of proliferative vitreoretinal diseases such as proliferative vitreoretinopathy (PVR).

Purpose: To investigate the effect of alkylphosphocholines (APCs) on human retinal pigment epithelium (RPE) attachment, spreading, migration, and microfilament assembly in vitro., Methods: Cultured RPE cells of five human donors were treated with one of four APCs (C18:1-PC, C20:1-PC, C21:1-PC, or C22:1-PC) in the presence of fetal calf serum. Cell viability was tested by the trypan blue exclusion assay. Attachment was assessed after a 2-hour incubation of RPE cells on coated 96-well-plates and subsequent MTT testing. Cellular spreading is characterized by cytoplasmic halo formation and was quantified by counting four separate fields of RPE cells allowed to spread on coated 24-well plates for 4 hours. Migration was measured by a modification of the Boyden chamber method in microchemotaxis chambers with polycarbonated filters. Microfilament assembly was assessed by immunofluorescence analysis after incubation with rhodamine-phalloidin., Results: All four APCs inhibited RPE cell attachment by more than 70% of their IC50 (C18:1-PC: 30 microM; C20:1-PC: 10 microM; C21:1-PC: 10 microM; and C22:1-PC: 10 microM). Also, APCs inhibited RPE cell spreading by more than 80% and migration by more than 90% at similar concentrations. Trypan blue staining revealed a toxicity within control limits within the concentration interval tested. Microfilament organization was significantly disturbed after incubation of RPE cells with one of the four APCs close to its IC50., Conclusions: APCs inhibit RPE cell attachment and spreading in vitro at nontoxic concentrations. As a possible mechanism of action, APCs disturb microfilament assembly, since they are known to interfere with protein kinase C (PKC) function. This could represent a novel method of preventing even early stages of proliferative vitreoretinal diseases like proliferative vitreoretinopathy (PVR).