Cre/LoxP Genetic Recombination Sustains Cartilage Anabolic Factor Expression in Hyaluronan Encapsulated MSCs Alleviates Intervertebral Disc Degeneration.

Long-Yi Chan,Shu-Jui Kuo,Chin-Yu Lin,Po-Liang Lai,Horng-Chaung Hsu,Cheng-Chung Chang,Tomoji Maeda

doi:10.3390/biomedicines10030555

Abstract

(1) Background: Inexplicable low back and neck pain frequently results from spinal disc degeneration with an imbalanced intervertebral disc (IVD) cell homeostasis. We hypothesize that introducing MSC expressing a sustained cartilage-anabolic factor in the IVD may stimulate the mucoid materials secreted from the IVD cells, promote the MSC’s chondrogenesis and maintain the hydration content providing mechanical strength to decelerate the disc degeneration progression; (2) Methods: This study expressed a cartilage-anabolic factor runx1 by a baculoviral vector (BV) transduced MSCs through a Cre/LoxP gene editing and recombination system for sustained recombinant runx1 transcription factor production. The Cre/LoxP BV modified MSCs were encapsulated by hyaluronan hydrogel, due to its’ vital composition in ECM of a healthy disc and transplanted to a punctured coccygeal disc in rats through micro-injection, followed by X-ray radiography and histological analysis at the 4- and 12-weeks post-transplantation; (3) Results: Data reveals the Cre/LoxP BV system-mediated long-termed runx1 gene expression, possessing good biosafety characteristics in the in vitro cell transduction and in vivo MSCs transplantation, and maintained superior hydration content in the disc than that of mock transduced MSCs; (4) Conclusions: This proof-of-concept study fulfills the need of implanting therapeutic cells accompanied with microinjection in the disc, such as a discography and paves a road to manufacture composite hyaluronan, such as peptide modified hyaluronan as an MSC carrier for IVD regeneration in the future study.

Highlights

Introduction distributed under the terms andWith global aging population, spine pathologies remain one of the leading causes of disability and financial burden, the medical devices development and healthy technology were largely improved in recent years
The intervertebral disc (IVD) is composed of a central hydrophilic proteoglycan-rich gelatinous matrix, the nucleus pulposus (NP), which is surrounded by a multilamellar collagenous ring, the annulus fibrosus (AF), and cartilaginous bony end-plates that separate the discs from the vertebrates [7]
To further confirm the functionality of bone marrows derived MSCs (BMSCs), the osteogenesis and chondrogenesis induced by culture medium alone were examined

Summary

Introduction

Spine pathologies remain one of the leading causes of disability and financial burden, the medical devices development and healthy technology were largely improved in recent years. Low back pain was one of the top three leading causes worldwide contributors of Years Lived with Disability (YLD) from 1990 to conditions of the Creative Commons. The economic burden of low back and neck problems in the USA is $85.9 billion, higher than that of many other causes of disability, including arthritis, and potentially fatal diseases such as cancer [2,3]. IVDs are the most crucial part of the healthy spinal column by providing stability while permitting motion between the vertebrae [6]. The complex structural features of IVDs enable them to absorb and disperse physical weight-loading from motion activities and other body parts. The gelatinous matrix-specific NP cells provide the extracellular matrix (ECM) components of the IVDs and maintain homeostasis

Methods

Results

Discussion

Conclusion