Comparative Experiments for Biocompatibility of the Nanocomposites Intended for Use in Artificial Conjunctiva

Abstract

Abstract: : Purpose: To evaluate the biocompatibility of the nanocomposites as a support for the artificial conjunctiva. Methods: 20 New Zealand white rabbits were used. Poly ε–caprolactone(PCL) nanocomposites alone, PCL coated with polyvinyl alcohol(PVA), PCL coated with polyvinyl pyrrolidone(PVP), PCL coated with chitosan and amniotic membrane as a control were cut into small discs with 5mm diameter. The discs were inserted underneath the conjunctiva of the rabbits through 3mm horizontal incision to measure the inflammation–inducing property. To investigate epithelial adhesion and goblet cell differentiation, discs were transplanted to the conjunctival defect after round excision of the conjunctiva whose diameter was 3mm, then were secured with interrupted suture. The number of inflammatory cells was counted in 5–consecutive HPFs in inserted–discs at 2 weeks. The amount of reepithelialization and the density of goblet cells were measured in transplanted discs using H&E and PAS staining at 2 weeks. Results: The numbers of inflammatory cells found inside the inserts were as follows: 21±4.9 for control, 21±15.1 for PCL, 49.6±26.0 for PVP coated PCL, 40.2±17.1 for chitosan coated PCL, 13.8±3.9 for PVA coated PCL. In PVA coated PCL, the accumulation of inflammatory cells was significantly lower than the control (p < 0.05, Mann whitney–U). Except PCL coated with chitosan, the reepithelization of conjunctival cell was accomplished more than 75% in all discs. We could find the differentiation of golblet cells in the order of amniotic membrane, PCL only and PCL coated with PVP. Conclusions: PCL only and PCL coated with PVA seemed to be biocompatible in rabbit conjunctiva, suggesting it can be a candidate for the use in artificial conjunctiva.

Keywords: conjunctiva • anterior segment