Mesenchymal Stem Cell Secretome Improves Tendon Cell Viability In Vitro and Tendon-Bone Healing In Vivo When a Tissue Engineering Strategy Is Used in a Rat Model of Chronic Massive Rotator Cuff Tear

Abstract

This work supports further investigation into the use of MSC secretome for priming TCs toward a more differentiated phenotype, and it promotes the tissue engineering strategy as a promising modality to help improve treatment outcomes for chronic MRCTs.

Comparative Evaluation of the Book‐Type Acellular Bone Scaffold and Fibrocartilage Scaffold for Bone‐Tendon Healing

“…Among the above three factors, the scaffolds play the most critical role, which can give structural support, mimic the in vivo microenvironment and biologically influence the local cells, so as to regenerate the injured tissue with high‐efficiency . Currently, to precisely control the stiffness, alignment and surface topology of the scaffold, lots of artificial polymer materials have been designed to fabricate the scaffold for B‐T healing, such as poly lactic‐co‐glycolic acid, poly‐ N ‐acetyl glucosamine and electrospun scaffolds . However, these scaffolds composed of polymer materials remain uncertain in biosafety and insufficient in bioactivity, thus partly limiting their application .…”

Biologics and stem cell‐based therapies for rotator cuff repair

“…Finally, immediate repair after laceration also does not mimic the clinical scenario in which tendon tears are usually left untreated for weeks or months prior to repair. To model delayed repair, a few groups recently carried out supraspinatus tendon detachment followed by surgical repair 3–16 weeks later . Prolonged unloading resulted in tendon retraction, muscle atrophy, fatty infiltration, and fibrotic scarring.…”

“…For example, naive MSCs are thought to be immunoprivileged and may exert immunomodulatory effects on the local environment via secreted factors . One study demonstrated a therapeutic effect of MSC‐conditioned media applied to injured rotator cuff . While enthesis healing was not determined, application of the MSC secretome inhibited muscle degeneration and atrophy.…”

“…To model delayed repair, a few groups recently carried out supraspinatus tendon detachment followed by surgical repair 3-16 weeks later. 34,[42][43][44][45][46][47] Prolonged unloading resulted in tendon retraction, muscle atrophy, fatty infiltration, and fibrotic scarring. Despite eventual repair, these studies generally suggested that the pathological events associated with unloading cannot be reversed by simple reattachment.…”

“…128 One study demonstrated a therapeutic effect of MSC-conditioned media applied to injured rotator cuff. 47 While enthesis healing was not determined, application of the MSC secretome inhibited muscle degeneration and atrophy. While still not definitively established, the immunomodulatory benefits of MSCs may be due to their effect on macrophage recruitment or polarization.…”