Yang Yi, Rossi Fabio M V, Putnins Edward E
Department of Oral Biological and Medical Sciences, Faculty of Dentistry, The University of British Columbia, 2199 Wesbrook Mall, Vancouver, B.C., Canada V6T 1Z3.
Biomaterials. 2007 Jul;28(20):3110-20. doi: 10.1016/j.biomaterials.2007.03.015. Epub 2007 Mar 18.
Bone marrow mesenchymal stromal cells (BM-MSC) are attractive candidates for connective tissue regeneration. Currently, their use is limited by poor overall cell survival and high apoptosis rates upon transplantation in vivo. We hypothesized that disruption of cell-extracellular matrix contact either during cell expansion or immediately prior to cell transplantation may impair cell viability and facilitate apoptosis. We therefore investigated whether BM-MSC can be expanded on microcarrier beads in spin culture and directly transplanted. This novel approach removes the need for the repeated trypsinizations that are usually required for expansion and transplantation. CultiSpher-S gelatin microcarrier beads supported Fisher and transgenic green fluorescent protein (GFP)(+) Sprague Dawley rat BM-MSC expansion. Bead-expanded BM-MSC could still be differentiated along the chondrogenic, osteogenic and adipogenic lineages. In the short term, direct subcutaneous transplantation of cells expanded on microcarriers was associated with significantly less apoptosis than trypsinized control cells. In the long term, BM-MSC expanded on microcarrier beads induced de novo trabecular bone formation in vivo. This novel approach present several advantages over current expansion-transplantation protocols for mesenchymal tissue regeneration.
骨髓间充质基质细胞（BM-MSC）是结缔组织再生的理想候选细胞。目前，它们的应用受到体内移植后总体细胞存活率低和凋亡率高的限制。我们推测，在细胞扩增过程中或细胞移植前立即破坏细胞与细胞外基质的接触可能会损害细胞活力并促进细胞凋亡。因此，我们研究了BM-MSC是否可以在旋转培养的微载体珠上扩增并直接移植。这种新方法无需通常扩增和移植所需的反复胰蛋白酶消化。CultiSpher-S明胶微载体珠支持Fisher大鼠和转基因绿色荧光蛋白（GFP）（+）的斯普拉格-道利大鼠BM-MSC的扩增。在微载体上扩增的BM-MSC仍可沿软骨生成、成骨和成脂谱系分化。短期内，直接皮下移植在微载体上扩增的细胞比胰蛋白酶消化的对照细胞凋亡明显减少。长期来看，在微载体珠上扩增的BM-MSC在体内诱导了新的小梁骨形成。这种新方法在间充质组织再生的当前扩增-移植方案方面具有几个优点。
