Effective Osteogenic Priming of Mesenchymal Stem Cells through LNA-ASOs-Mediated Sfrp1 Gene Silencing.

María Isabel Pérez-Núñez,Flor M. Pérez-Campo,Ricardo Reyes,Patricia García-García,Carmen Évora,José Carlos Rodríguez-Rey,José A. Riancho,Daniel García-Sánchez,Alberto González-González

doi:10.3390/pharmaceutics13081277

Abstract

Mesenchymal stem cell (MSC) transplantation has emerged as a promising approach for bone regeneration. Importantly, the beneficial effects of MSCs can be improved by modulating the expression levels of specific genes to stimulate MSC osteogenic differentiation. We have previously shown that Smurf1 silencing by using Locked Nucleic Acid-Antisense Oligonucleotides, in combination with a scaffold that sustainably releases low doses of BMP-2, was able to increase the osteogenic potential of MSCs in the presence of BMP-2 doses significantly smaller than those currently used in the clinic. This would potentially allow an important reduction in this protein in MSs-based treatments, and thus of the side effects linked to its administration. We have further improved this system by specifically targeting the Wnt pathway modulator Sfrp1. This approach not only increases MSC bone regeneration efficiency, but is also able to induce osteogenic differentiation in osteoporotic human MSCs, bypassing the need for BMP-2 induction, underscoring the regenerative potential of this system. Achieving successful osteogenesis with the sole use of LNA-ASOs, without the need of administering pro-osteogenic factors such as BMP-2, would not only reduce the cost of treatments, but would also open the possibility of targeting these LNA-ASOs specifically to MSCs in the bone marrow, allowing us to treat systemic bone loss such as that associated with osteoporosis.

Highlights

Mesenchymal stem cells (MSCs) are multipotent cells present in different adult tissues that possess the capacity to differentiate into various specialized cell lineages including osteoblasts, adipocytes, and chondrocytes
We describe here how Sfrp1 silencing in MSCs can considerably accelerate bone formation both in vitro and in vivo in an ectopic mouse model, something that could be advantageous in clinical practice, for example, to reduce the length of fracture healing
Transfection efficiency achieved by using this method was always over 90%, as shown by the control fluorescent GapmeR internalization measured by flow cytometry

Summary

Introduction

Mesenchymal stem cells (MSCs) are multipotent cells present in different adult tissues that possess the capacity to differentiate into various specialized cell lineages including osteoblasts, adipocytes, and chondrocytes. Due to this ability, in the last few years, there has been an increasing interest in using MSCs-based approaches to improve bone repair and regeneration [1]. The use of MSCs-based therapies would benefit the treatment of critical size bone defects resulting from direct trauma or from the removal of large bone areas through surgical procedures in patients with osteosarcoma, osteonecrosis, or other pathologies. Pharmaceutics 2021, 13, 1277 osteogenic differentiation of the transplanted cells. Different MSCs modifications have been designed to achieve this point [2,3,4,5]

Methods

Results

Conclusion