Farnebo Simon, Farnebo Lovisa, Kim Maxwell, Woon Colin, Pham Hung, Chang James
VA Palo Alto Health Care System, Livermore, CA, USA; Linköping University, Sweden.
Stanford University, CA, USA.
Hand (N Y). 2017 Jan;12(1):68-77. doi: 10.1177/1558944715628005. Epub 2016 Mar 15.
Tendon-derived extracellular matrix (ECM) hydrogel has been shown to augment tendon healing in vivo. We hypothesized that reseeding of the gel with adipose-derived stem cells (ASCs) could further assist repopulation of the gel and that combinations of growth factors (GFs) would improve the survival of these cells after reseeding. A tendon-specific ECM solution was supplemented with varying concentrations of basic fibroblast growth factor (bFGF), insulin-like growth factor-1 (IGF-1), and platelet-derived growth factor-BB (PDGF-BB). Gels were then seeded with ASCs transfected with a green fluorescent protein/luciferin construct. Cell proliferation was determined using the MTT assay and histology, and GF and ASC augmented gels were injected into the back of Sprague Dawley rats. Bioluminescence of seeded gels was continuously followed after reseeding, and cell counts were performed after the gels were explanted at 14 days. Synergistic effects of the GFs were seen, and an optimal combination was determined to be 10 ng/mL bFGF, 100 ng/mL IGF-1, and 100 ng/mL PDGF-BB (2.8-fold increase; < .05). In vivo bioluminescence showed an improved initial survival of cells in gels supplemented with the optimal concentration of GF compared with the control group (10.6-fold increase at 8 days; < .05). Cell counts of explants showed a dramatic endogenous repopulation of gels supplemented by GF + ASCs compared with both gels with GF but no ASCs (7.6-fold increase) and gels with ASCs but no GF (1.6-fold increase). Synergistic effects of GFs can be used to improve cellular proliferation of ASCs seeded to a tendon ECM gel. Reseeding with ASCs stimulates endogenous repopulation of the gel in vivo and may be used to further augment tendon healing.
肌腱衍生的细胞外基质（ECM）水凝胶已被证明可在体内促进肌腱愈合。我们假设用脂肪来源的干细胞（ASC）重新接种凝胶可以进一步帮助凝胶重新填充，并且生长因子（GF）的组合将改善重新接种后这些细胞的存活。向肌腱特异性ECM溶液中补充不同浓度的碱性成纤维细胞生长因子（bFGF）、胰岛素样生长因子-1（IGF-1）和血小板衍生生长因子-BB（PDGF-BB）。然后将用绿色荧光蛋白/荧光素构建体转染的ASC接种到凝胶中。使用MTT法和组织学测定细胞增殖，并将GF和ASC增强的凝胶注射到Sprague Dawley大鼠的背部。重新接种后持续跟踪接种凝胶的生物发光，并在14天后将凝胶取出后进行细胞计数。观察到GF的协同作用，确定最佳组合为10 ng/mL bFGF、100 ng/mL IGF-1和100 ng/mL PDGF-BB（增加2.8倍；P<0.05）。体内生物发光显示，与对照组相比，补充最佳浓度GF的凝胶中细胞的初始存活率有所提高（8天时增加10.6倍；P<0.05）。与仅含GF但不含ASC的凝胶（增加7.6倍）和仅含ASC但不含GF的凝胶（增加1.6倍）相比，取出物的细胞计数显示，GF+ASC补充的凝胶有显著的内源性重新填充。GF的协同作用可用于改善接种到肌腱ECM凝胶中的ASC的细胞增殖。用ASC重新接种可刺激凝胶在体内的内源性重新填充，并可用于进一步促进肌腱愈合。
