A Nanofibrillar Surface Promotes Superior Growth Characteristics in Cultured Human Retinal Pigment Epithelium

Abstract

Background: To evaluate the influence of surface topography on the proliferation of the retinal pigment epithelium (RPE) by comparing nanofibrillar and smooth substrates. Methods: Electrospun polyamide nanofibers (EPN) are an engineered surface mimicking native basement membranes. Commonly used plastic (polystyrene, PS) and glass substrates have a smooth topography. All were analyzed by scanning electron microscopy. RPE cultures were established from fetal and adult donors. Growth curves were established on the above substrates. Cell cycle and growth fractions were analyzed with 5-ethynyl-2′-deoxyuridine (EdU) and 4′,6-diamidino-2-phenylindole (DAPI). Results: At a magnification of ×5,000, EPN showed randomly overlapping fibers and pores. The surface of glass was slightly studded yet regular, in contrast to ideally smooth PS. Polygonal cells grew on nanofibers in a colony-like distribution, while randomly spread spindle-shaped cell morphologies were seen on smooth surfaces. This was observed at all donor ages. Initial proliferation rates were higher on EPN, and similar final cell densities were reached in all age groups, compared to an age-related decline on PS. EdU/DAPI revealed faster cell cycles on EPN. Growth fractions were higher and maintained longer on EPN. Observed substrate differences in growth behavior were statistically significant. Conclusion: Surface topography appears to induce distinct RPE proliferation characteristics.

The influences of purple sweet potato anthocyanin on the growth characteristics of human retinal pigment epithelial cells

“…3c and 3d) of RPE when treated with 100 µg/ml PSPA for 2 to 3 days, which had shown normal mitosis and more living cells with higher viability compared to the control group, it was clear that PSPA promoted DNA synthesis, which took place in the S-phase, rather than inducing cell cycle blockage. Cells undergo DNA synthesis in the S-phase, and DNA synthesis rates are determined as a proportion of the cell population in the S-phase or growth phase to indicate cell proliferation (32, 33). Moreover, an increase in the percentage of the RPE cell population in the S-phase of the cell cycle was also found in thrombin-induced RPE cell proliferation (34).…”

Optimization of Storage Temperature for Cultured ARPE-19 Cells

“…Several laboratories have investigated the cultivation of RPE cells on artificial substrates, aiming to identify carrier materials that could be directly transplanted into the subretinal space [15, 45, 46]. However, there is currently no consensus in regard to the future use of culture substrates for RPE transplantation.…”

Assessing the Suitability of Electrospun Poly(Ethylene Terephthalate) and Polystyrene as Cell Carrier Substrates for Potential Subsequent Implantation as a Synthetic Bruch's Membrane

“…Cells grew in patches [16] starting to form monolayers in the short-term culture. Fluorescence images for PS also showed cell presence only on UV=ozone treated surfaces, although not in the monolayer morphology as exhibited on PET, but wrapped around individual fibers due to the larger distance between PS fibers [35,36].…”

“…Although both PET and EPN showed very good cell response, EPN has been described as being a better surface for RPE cell replication, due to its fibrous structure [10,12]. Fibrous surfaces have been previously reported to allow cells to exhibit a more in vivo-like morphology than compared to when grown on planar surfaces [13][14][15][16] and since the native BM is fibrous [8] it would be ideal if the cell carrier substrate were to also mimic this fibrous structure.…”