A collagen-based corneal stroma substitute with micro-designed architecture
A 3D corneal stroma substitute with micro-level patterns was constructed from a stack of 4 micro patterned collagen or collagen–elastin like recombinamer (Col:ELR) blend layers. The transparency of all of the films was quite high with the uncrosslinked (UXL) films and dehydrothermally treated (150 °C, 24 h) Col:ELR films yielding the best results. Human corneal keratocytes (HK) could be attached and proliferated equally well on the single films of Col and Col:ELR. However, for the multilayer constructs the proliferation was higher on Col than on Col:ELR. The cells were found to align along the patterns (microchannels with a 39 μm groove depth, 8 μm groove width, 3.3 μm ridge width, and 54.7° inclination angle) of the films, while no significant alignment was observed on the unpatterned films. The transparency of the seeded Col:ELR films was superior to the Col films over a 30 day incubation period and was quite close to that of a native human cornea. It was concluded that the Col and Col:ELR films and their 3D constructs have significant potential for use as corneal stroma substitutes.