Healthy Tendon Stem Cell-Derived Exosomes Promote Tendon-to-Bone Healing of Aged Chronic Rotator Cuff Tears by Breaking the Positive-Feedback Cross-Talk Between Senescent Tendon Stem Cells and Macrophages through the Modulation of Macrophage Polariza

Investigators found a positive feedback cross-talk between senescent tendon stem cells (s-TSCs) and macrophages. The conditioned medium from s-STCs could promote macrophage polarization mainly toward the M1 phenotype, whose CM reciprocally accelerated further s-TSC senescence.