Abstract
Purpose:
Current methods to replace traumatized corneal endothelium involve the placement of partial or full thickness grafts. However, in the presence of inflammation, these grafts perform poorly and are not an optimal long term solution. An alternative, non-graft treatment for corneal endothelium repair is needed. The overall hypothesis is that corneal endothelial cells (CEC), loaded with superparamagnetic iron oxide nanoparticles (SPIONPs), can be injected into the anterior chamber of the eye while being exposed to a constant external magnetic field and be strategically targeted to damaged areas of the inner cornea. In this study, we investigate the in vitro biological effects of SPIONPs on corneal endothelial cells.
Methods:
Bovine corneal endothelial cells (BCECs; Astarte Biologics) were cultured in DMEM and 10% FBS. BCECs were seeded in 48 well plates and maintained in culture for 48 hours. Biotin coated SPIONPs (Micromod, Rostock Germany) were added to the wells at 0, 1x106, 10x106, and 100x106 SPIONPs per cell. SPIONP uptake was confirmed with Prussian blue staining. Cell viability was determined via MTT and Live/Dead staining after being in the presence or absence of a magnetic field. The effect of magnetic force on BCEC cytoskeletal structure was evaluated using rhodamine phalloidin staining. Comparisons between groups were made using either a two tailed t-test or a one-way analysis of variance with values of p ≤ 0.05 considered statistically significant.
Results:
BCEC viability was maintained at all SPIONP concentrations over three days with the exception of 100x106 SPIONPs per cell, where a significant decrease (p<0.05) in viability occurred. Furthermore, BCEC viability significantly increased (p<.05) upon exposure to magnetic force at all SPIONP concentrations tested. There were no observed differences in the arrangement of actin filaments within the cytoskeletal structure of any conditions evaluated.
Conclusions:
These results demonstrate that SPIONP loaded endothelial cells have potential for magnetically controlled cell guidance, as their viability and cytoskeletal structure were unaffected upon SPIONP incorporation and exposure to magnetic force. The information gleaned from this study will help advance cell guided delivery technology of human CECs to the damaged corneal endothelium, thus providing an alternative therapeutic option to corneal grafting.