3D printing of microneedle arrays for hair regeneration in a controllable region

Abstract

Hair loss is a common skin disease that causes intense emotional suffering. Hair regeneration in a personalized area is highly desirable for patients with different balding conditions. However, the existing pharmaceutical treatments have difficulty precisely regenerating hair in a desired area. Here, we show a method to precisely control the hair regeneration using customized microneedle arrays (MNAs). The MNA with a customized shape is fast fabricated by a static optical projection lithography process in seconds, which is a 3D printing technology developed by our group. In the mouse model, MNA treatment could induce hair regrowth in a defined area corresponding to the customized shape of MNA. And the regenerated hair promoted by MNAs had improved quality. Cellular and molecular analysis indicated that MNA treatment could recruit macrophages in situ and then initiate the proliferation of hair follicle stem cells, thereby improving hair regeneration. Meanwhile, the activation of the Wnt/β-catenin signaling pathway was observed in hair follicles. The expressions of Hgf, Igf 1 and Tnf-α were also upregulated in the treated skin, which may also be beneficial for the MNA-induced hair regeneration. This study provides a strategy to precisely control hair regeneration using customized microneedle arrays by recruiting macrophages in situ, which holds the promise for the personalized treatment of hair loss.

Transdermal Drug Delivery System: Current Status and Clinical Application of Microneedles

“…In comparison to conventional manufacturing methods, 3D printing reduces labor and equipment costs in the production process. Moreover, it optimizes the utilization of raw materials, minimizes waste, and lowers production costs. ,, Additionally, 3D printing technology facilitates customized production of microneedles tailored to individual requirements. , By adjusting design parameters, the shape, size, and structure of microneedles can be easily modified to meet diverse clinical needs. , It also enables the realization of complex structures and integration of multiple functions in microneedles. − By incorporating intricate details and functionalities during the design and printing process, the performance and efficacy of microneedles can be enhanced to cater to a wider range of clinical requirements. Furthermore, the utilization of renewable and biodegradable materials in printing further enhances the sustainability of microneedles while minimizing their environmental impact. , Additionally, as a versatile medical tool, microneedles must be capable of accommodating diverse treatment needs and application scenarios.…”

“…110,111 By adjusting design parameters, the shape, size, and structure of microneedles can be easily modified to meet diverse clinical needs. 112,113 It also enables the realization of complex structures and integration of multiple functions in microneedles. 114−116 By incorporating intricate details and functionalities during the design and printing process, the performance and efficacy of microneedles can be enhanced to cater to a wider range of clinical requirements.…”

Dissolving microneedles for transdermal drug delivery in cancer immunotherapy

“…3D printing technology is an emerging additive manufacturing technology that can easily, flexibly, and rapidly achieve the customization of elaborate structures and personalized shapes, which has received significant attention. [35][36][37] Recently, static optical projection lithography (SOPL) [38][39][40] and magnetorheological drawing lithography (MDL) 41 have received great attention. These novel 3D printing methods, based on the process of emerging layer by layer, are able to avoid the stepped surface associated with traditional 3D printing technologies.…”