Comparison of the efficacy of seven types of microneedles for treating a rabbit hypertrophic scar model

Microneedle technology can effectively suppress the formation of hypertrophic scarring in both animals and humans. Our previous research has revealed that this is due to the physical contact inhibition effect by using microneedles made of liquid-crystal polymers as the model device. One important factor we didn't study is the influence of the fabrication materials of microneedles. Therefore, this article examines this key point on a rabbit ear hypertrophic scar model. We monitor the thickness of the scars, and the expression of α-SMA and Ki-67 protein, and TGF-β1 mRNA in a period of 42 days. Among microneedles made of 6 polymeric materials and stainless steel, polymethylmethacrylate microneedles present superiority in all aspects including the reduction of tissue fibrosis, and the expression of α-SMA, Ki-67 protein and TGF-β1 mRNA. On the other hand, polycarbonates, polyurethane, and polylactic-co-glycolic acid microneedles could suppress three biomarker expressions.