Tissue engineering a tendon-bone junction with biodegradable braided scaffolds

Abstract

Background Tendons play an important role in transferring stress between muscles and bones and in maintaining the stability of joints. Tendon tears are difficult to heal and are associated with high recurrence rates. So, the objective of this study was to develop a biodegradable scaffold for tendon-bone junction regeneration. Methods Two types of polylactic acid (PLA) yarns, having fibers with round and four deep grooved cross-sections, were braided into tubular scaffolds and cultured with murine Transforming growth factor beta type II receptor (Tgfbr2)-expressing joint progenitor cells. The scaffolds were designed to mimic the mechanical, immuno-chemical and biological properties of natural mouse tendon-bone junctions. Three different tubular scaffolds measuring 2 mm in diameter were braided on a Steeger 16-spindle braiding machine and biological and mechanical performance of the three scaffolds were evaluated. Results The mechanical test results indicated that three different braided scaffold structures provided a wide range of mechanical properties that mimic the components of tendon bone junction and results of the biological tests confirmed cell viability, active cell attachment and proliferation throughout all three scaffolds. Conclusions This study has identified that the three proposed types of braided scaffolds with some improvement in their structures have the potential to be used as scaffolds for the regeneration of a tendon bone tissue junction.

Fibrous Systems as Potential Solutions for Tendon and Ligament Repair, Healing, and Regeneration

“…More specifically, three different tissue regions should be designed: tendon/ligament, fibrocartilage interface and bone. [ 206 ]…”

“…This phenomenon can create a considerable properties mismatch between tendon/ligament and bone regions, often leading to refailure. [ 206 ]…”

“…Several fiber‐based platforms have been developed for this application, including knitted, braided, electrospun, and multilayered systems. [ 206–208 ] In this frame, the knitting technology was applied to fabricate a silk construct, further combined with aligned collagen fibers. The authors presented bone marrow stem cells adhesion and osteogenic differentiation in vitro, while adequate biomechanical properties were detected in vivo.…”

“…The different braided regions showed zonal mechanical characteristics, recapitulating the tissue junction properties. [ 206 ]…”

Biomaterials for stem cell engineering and biomanufacturing

“…In addition, GAG [90] was introduced to promote scaffold, cellular and biological cue interactions as it has strong affinity to growth factors for directing cell fate. PLA [91], PLGA [92], PCL [93] and polyurethane (PU) [94] are popular synthetic biomaterials for bone/cartilage tissue engineering. Among them, PCL stood out for its superior short-term and long-term biocompatibility due to non-inflammatory and nontoxic degradation products [[145], [146], [147]], unlike acid-releasing PLA and PLGA.…”