Biofabricating hollow microneedle array with controllable microstructure for cell transplantation.

Microneedles improve upon the direct injection method by piercing the epidermis to create microchannels for drug delivery in a painless and minimally invasive way. With these microchannels, large macromolecules can penetrate the skin barrier to reach the underlying target tissue. In this study, poly(methyl methacrylate) (PMMA) hollow microneedles (HMN) arrays were fabricated to transplant cells. The result showed that HMN arrays have good biocompatibility. Human epidermal melanocytes and follicle dermal papilla cells were shown to be successfully delivered to acellular porcine skin tissue. Similarly, human corneal keratocytes and corneal epithelial cells were shown to be successfully delivered to acellular porcine corneal tissue. The delivered cells proliferated and penetrated into the tissue. This system may have the potential in the application of cell delivery or cell transplantation.