Advances in electrospun scaffolds for meniscus tissue engineering and regeneration

Abstract

The meniscus plays a critical role in maintaining the homeostasis, biomechanics, and structural stability of the knee joint. Unfortunately, it is predisposed to damages either from sports-related trauma or age-related degeneration. The meniscus has an inherently limited capacity for tissue regeneration. Self-healing of injured adult menisci only occurs in the peripheral vascularized portion, while the spontaneous repair of the inner avascular region seems never happens. Repair, replacement, and regeneration of menisci through tissue engineering strategies are promising to address this problem. Recently, many scaffolds for meniscus tissue engineering have been proposed for both experimental and preclinical investigations. Electrospinning is a feasible and versatile technique to produce nano-to micro-scale fibers that mimic the microarchitecture of native extracellular matrix and is an effective approach to prepare nanofibrous scaffolds for constructing engineered meniscus. Electrospun scaffolds are reported to be capable of inducing colonization of meniscus cells by modulating local extracellular density and stimulating endogenous regeneration by driving reprogramming of meniscus wound microenvironment. Electrospun nanofibrous scaffolds with tunable mechanical properties, controllable anisotropy, and various porosities have shown promises for meniscus repair and regeneration and will undoubtedly inspire more efforts in exploring effective therapeutic approaches towards clinical applications. In this article, we review the current advances in the use of electrospun nanofibrous scaffolds for meniscus tissue engineering and repair and discuss prospects for future studies.

Cyclic freeze–thaw grinding to decellularize meniscus for fabricating porous, elastic scaffolds

“…4,45 Sufficient mechanical properties are a prerequisite for substitutes toward meniscus repair and regeneration. 27 Although many studies reported that bulk dmECM scaffolds had slightly decreased or even comparable compression strength with the native meniscus tissue, [50][51][52] they might be not optimal for implanting because of their dense matrix structure that does not allow cellular infiltration and poorly integrates with host tissue. 20,21 Previously, we reported a protocol to process dmECM into a formulation of injectable hydrogel, 8 which is compatible with cellular infiltration and integration with host tissue and has been widely exploited for meniscus repair in many preclinical investigations.…”

“…Sufficient mechanical properties are a prerequisite for substitutes toward meniscus repair and regeneration 27 . Although many studies reported that bulk dmECM scaffolds had slightly decreased or even comparable compression strength with the native meniscus tissue, 50–52 they might be not optimal for implanting because of their dense matrix structure that does not allow cellular infiltration and poorly integrates with host tissue 20,21 .…”

“…Despite good bioactivity and flexibility, the relatively soft nature of hydrogels might limit their applicability. Incorporating dmECM into synthetic polymers for electrospinning to generate nanofibers provides an alternative to preparing meniscus scaffolds 27 . We have shown that manipulation of electrospun nanofibers through special collectors is effective in recapitulating the hierarchical fibrous structure of the meniscus 14 .…”

“…Incorporating dmECM into synthetic polymers for electrospinning to generate nanofibers provides an alternative to preparing meniscus scaffolds. 27 We have shown that manipulation of electrospun nanofibers through special collectors is effective in recapitulating the hierarchical fibrous structure of the meniscus. 14 Electrospun scaffolds incorporated with dmECM exhibit biomimetic ultrastructure and larger pore size, allowing intensive cell infiltration and upregulating meniscus-associated gene expression and extracellular matrix deposition.…”

Pneumatospinning Biomimetic Scaffolds for Meniscus Tissue Engineering

“…However, a central feature that underlies the load bearing role of meniscus is the unique organization of collagen fibers, which is an essential requirement for a functional engineered meniscus. To this end, we, and other groups, have applied electrospinning (ES) to create nanofibrous scaffolds that emulate the meniscus collagen fibrillar matrix using natural and synthetic polymer (Grogan et al, 2020;Wang et al, 2021).…”