Cornea - ARVO

ARVO 2013 Annual Meeting Abstracts by Scientific Section/Group - Corneastudy was to evaluate the in vivo functionality, ultrastructure andbiocompatibility of allogeneic and xenogeneic tissue-engineered (TE)stromal grafts in the feline model.Methods: Human and feline keratocytes were isolated from normalcorneas and cultured to tissue engineer a 6 sheet-stromal substituteusing a self-assembly approach. Eight healthy animals underwent twointra-stromal grafts in one eye and the controlateral eye was used as acontrol. Animals were followed during 4 months after surgery, withslit lamp ophthalmic examination, intraocular pressure measurementand in vivo optical coherent tomography (Thorlabs®). Histology andtransmission electron microscopy (TEM) were performed on allcorneas at 4 months.Results: 16 grafts were performed. The average graft transparencyscore (0 (opaque) to 4 (crystal clear) scale) was 3.3±0.4 on Day 1 and3.9±0.2 on Day 37, which was similar to that of normal controls. Theminimal intraocular inflammation (cells and flare) observed in alleyes on Day 1 entirely resolved on Day 10. The mean graft thicknessdecreased with edema resorption (Day 3: 44.5±8 µm; Day 114:31.4±5 µm). Intraocular pressure remained unchanged (Preop:11.8±3.6; Postop: 11.7±3.0 mmHg). The grafts did not attract cornealvessels. Mean corneal endothelial cell counts remained stable (Preop:2506±77 cells/mm2; Postop: 2482±70 cells/mm2). Histology showednicely integrated grafts, with undisturbed host corneal epithelium,stroma, and endothelium. TEM confirmed the normal aspect of thekeratocytes, found in greater number in the grafts, and the absence ofinflammatory cells. Spacing between the collagen fibers of the TEstromawas 33.55±7.21 nm prior to transplantation, due to edema,and 25.90±4.68 nm 4 months after transplantation, with a regulararrangement similar to that of normal native stromas. All results werestatistically significant (p