The regenerative capacity of cell imprinting and collagen/PCL scaffolds in gastrocnemius tendon defect

Traumatic tendon injuries are among the most common types of injuries, often characterized by insufficient and slow recovery. The current study aims to evaluate the regenerative capacity of a tissue-engineered tendon graft in a rabbit gastrocnemius tendon defect. This graft comprises gap-electrospun collagen-coated parallel polycaprolactone (PCL) fibers seeded with adipose-derived stem cells (ADSCs), which promoted to adopt a tenogenic phenotype using a tenocyte-imprinted substrate for the first time. Scanning electron microscopy (SEM) images confirmed the parallel structure and successful cell attachment to the scaffold. Sirius red staining, high-performance X-ray photoelectron spectroscopy, and water contact angle showed that collagen successfully coated and changed the surface hydrophilicity of the scaffold. Imprinted substrates showed tenocyte patterns in SEM images. In an in vitro evaluation, ICC and real-time polymerase chain reaction confirmed that the stem cells acquired tenogenic traits. In addition, histopathology scoring outcomes showed significant improvement in the Pattern group and an almost 2.58 times increase in the total score average compared to the control group. In vitro and in vivo therapy results show that differentiated ADSCs seeded on the collagen-coated PCL scaffold for tendon repair have astounding therapeutic potential.