Microchannels in nano-submicro-fibrous cellulose scaffolds favor cell ingrowth

Micropatterned pores in scaffolds have been extensively used to promote mass transport, tissue integration, and vascularization. However, the combined effects of microchannels and biomimetic structure on cell functions have not been investigated. Herein, microchannels with varying diameters of about 100, 200, and 400 μm were fabricated in the scaffolds composed of nanofibrous (diameter < 100 nm) bacterial nanocellulose and submicro-fibrous (diameter = 100–1000 nm) saponified cellulose acetate. The nano-submicro-fibrous cellulose scaffolds with microchannels were fabricated by combining electrospinning, step-by-step in situ biosynthesis, and laser-aided punching. It is found that the presence of microchannels favors cell proliferation and migration at an optimum microchannel size. More importantly, the microchannels and nano-submicro-fibrous wall morphology show a synergistic effect in promoting cell migration. These results suggest that the biomimetic nano-submicro-fibrous cellulose scaffolds with microchannels show promising applications in tissue engineering and regenerative medicine.