Detalle de: Calcium phosphate glass improves angiogenesis capacity of poly(lactic acid) scaffolds and stimulates differentiation of adipose tissue-derived mesenchymal stromal cells to the endothelial lineage

The angiogenic capacity of a new biomaterial composite of poly(lactic acid) and calcium phosphate glass (PLA/CaP) was analyzed by noninvasive bioluminescence imaging (BLI) and histological procedures. Human adipose tissue‐derived mesenchymal stromal cells expressing cytomegalovirus (CMV) promoter regulated Photinus pyralis luciferase (hAMSC‐PLuc) grew up to 30 times the initial cell load, in vitro , when seeded in PLA/CaP scaffolds, but suffered an initial growth crisis followed by recovery when the scaffolds were subcutaneously implanted in SCID mice. To analyze changes in gene expression, hAMSC‐PLuc cells were double labeled with a CMV promoter regulated Renilla reniformis luciferase and a Photinus pyralis luciferase reporter regulated by either the PECAM promoter or a hypoxia response element (HRE) artificial promoter and seeded in PLA/CaP and PLA scaffolds implanted in SCID mice. Analysis by BLI showed that hAMSCs in scaffolds were induced to differentiate to the endothelial lineage and did this faster in PLA/CaP than in PLA scaffolds. Endothelial differentiation correlated with a decrease in the activity of HRE regulated luciferase expression, indicative of a reduction of hypoxia. Histological analysis showed that PLA/CaP scaffolds were colonized by a functional host vascular system. Moreover, colonization by isolectin B 4 positive host cells was more effective in PLA/CaP than in PLA scaffolds, corroborating BLI results. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.