Hand (N Y). 2018 Aug 6:1558944718792708. doi: 10.1177/1558944718792708. [Epub ahead of print]

The Effect of Growth Differentiation Factor 8 (Myostatin) on Bone Marrow-Derived Stem Cell-Coated Bioactive Sutures in a Rabbit Tendon Repair Model.

Muraoka K^1,2, Le W¹, Behn AW¹, Yao J¹.

Abstract

BACKGROUND:

We have reported that bioactive sutures coated with bone marrow-derived mesenchymal stem cells (BMSCs) enhance tendon repair strength in an in vivo rat model. We have additionally shown that growth differentiation factor 8 (GDF-8, also known as myostatin) simulates tenogenesis in BMSCs in vitro. The purpose of this study was to determine the possibility of BMSC-coated bioactive sutures treated with GDF-8 to increase tendon repair strength in an in vivo rabbit tendon repair model.

METHODS:

Rabbit BMSCs were grown and seeded on to 4-0 Ethibond sutures and treated with GDF-8. New Zealand white rabbits' bilateral Achilles tendons were transected and randomized to experimental (BMSC-coated bioactive sutures treated with GDF-8) or plain suture repaired control groups. Tendons were harvested at 4 and 7 days after the surgery and subjected to tensile mechanical testing and quantitative polymerase chain reaction.

RESULTS:

There were distinguishing differences of collagen and matrix metalloproteinase RNA level between the control and experimental groups in the early repair periods (day 4 and day 7). However, there were no significant differences between the experimental and control groups in force to 1-mm or 2-mm gap formation or stiffness at 4 or 7 days following surgery.

CONCLUSIONS:

BMSC-coated bioactive sutures with GDF-8 do not appear to affect in vivo rabbit tendon healing within the first week following repair despite an increased presence of quantifiable RNA level of collagen. GDF-8's treatment efficacy of the early tendon repair remains to be defined.