Fol. Biol. 2018, 64, 155-166
Bone Marrow-Derived Cells Participate in Composition of the Satellite Cell Niche in Intact and Regenerating Mouse Skeletal Muscle
The cellular components of the satellite cell niche participate in the regulation of skeletal muscle regeneration. Beside myogenic cells at different developmental stages, this niche is formed by cells of the immune system, the interstitial connective tissue and the vascular system. Unambiguous determination of the origin of these cell types could contribute to optimization of the cell-based therapy of skeletal muscle disorders. In our work, we intravenously transplanted mouse GFP+ unseparated bone marrow cells into whole-body lethally irradiated immunocompetent mice four weeks before cardiotoxin-induced injury of the recipients’ skeletal muscles. Seven and 28 days after the toxin injection, the injured regenerating and contralateral intact muscles were examined for identification of GFP+ bone marrow-derived cells by direct fluorescence, protein immunohistochemistry and immunogold transmission electron microscopy. In both the intact and injured muscles, GFP positivity was determined in immune cells, mainly in macrophages, and in interstitial spindleshaped cells. Moreover, in the injured muscles, rare GFP+ endothelial cells of the blood vessels and newly formed myotubes and muscle fibres were present. Our results confirmed the ability of bone marrowderived cells to contribute to the cellular component of the satellite cell niche in the intact and regenerating skeletal muscle. These cells originated not only from haematopoietic stem cells, but obviously also from other stem or progenitor cells residing in the bone marrow, such as multipotent mesenchymal stromal cells and endothelial progenitors.
Keywords
satellite cells, bone marrow cells, satellite cell niche, transplantation, skeletal muscle regeneration.
Funding
This work was supported by grant project No. 15-09161S from the Grant Agency of the Czech Republic and grant project PROGRES Q40/06 and Q40/09 from the Ministry of Education, Youth and Sports of the Czech Republic.
References
Copyright
This is an open-access article distributed under the terms of the Creative Commons Attribution License.
