An In Vitro Comparison of the Neurotrophic and Angiogenic Activity of Human and Canine Adipose-Derived Mesenchymal Stem Cells (MSCs): Translating MSC-Based Therapies for Spinal Cord Injury.

Ibtesam R T Al Delfi,William E B Johnson,Peter Myint,Louis D V Johnson,Chelsea R Wood,John F Innes,Martyn D Snow

doi:10.3390/biom10091301

Abstract

The majority of research into the effects of mesenchymal stem cell (MSC) transplants on spinal cord injury (SCI) is performed in rodent models, which may help inform on mechanisms of action, but does not represent the scale and wound heterogeneity seen in human SCI. In contrast, SCI in dogs occurs naturally, is more akin to human SCI, and can be used to help address important aspects of the development of human MSC-based therapies. To enable translation to the clinic and comparison across species, we have examined the paracrine, regenerative capacity of human and canine adipose-derived MSCs in vitro. MSCs were initially phenotyped according to tissue culture plastic adherence, cluster of differentiation (CD) immunoprofiling and tri-lineage differentiation potential. Conditioned medium (CM) from MSC cultures was then assessed for its neurotrophic and angiogenic activity using established cell-based assays. MSC CM significantly increased neuronal cell proliferation, neurite outgrowth, and βIII tubulin immunopositivity. In addition, MSC CM significantly increased endothelial cell migration, cell proliferation and the formation of tubule-like structures in Matrigel assays. There were no marked or significant differences in the capacity of human or canine MSC CM to stimulate neuronal cell or endothelial cell activity. Hence, this study supports the use of MSC transplants for canine SCI; furthermore, it increases understanding of how this may subsequently provide useful information and translate to MSC transplants for human SCI.

Highlights

Much research has been performed to better understand the effects of spinal cord injury (SCI) and it sequelae, and how best to repair the damage caused and alleviate the loss of function
The human and canine cells isolated and culture-expanded from adipose tissue fulfilled the criteria previously proposed by the International Society for Cellular Therapy (ISCT) to be considered mesenchymal stem cell (MSC) [24]
Following analysis by flow cytometry, the human and canine cell cultures showed a lack of immunoreactivity for the hematopoietic cluster of differentiation (CD) markers, i.e., CD34 and CD45, while showing immunopositivity for the MSC-associated markers, i.e., CD44 and CD90, with each marker being detected in greater than 90% of all cell populations (Figure 1c)

Summary

Introduction

Much research has been performed to better understand the effects of spinal cord injury (SCI) and it sequelae, and how best to repair the damage caused and alleviate the loss of function. Rats inflicted with a complete contusion SCI recover a capacity for weight-bearing and some movement within 1–2 weeks of injury, as determined by observational scoring, whilst humans can remain with a complete loss of motor function for life [5]. Because SCI does not naturally occur in rodents, the injury must be induced in a controlled laboratory setting. This benefits analysis of specific neuronal defects, interventions and experimental reproducibility; it does not address the natural heterogeneity of human SCI, or the likely heterogeneity of new treatment outcomes [6,7]

Results

Discussion

Conclusion