Nano-bioactive glass incorporated polymeric apatite/tricalcium phosphate cement composite supports proliferation and osteogenic differentiation of human adipose-derived stem/stromal cells

Abstract

Apatite/Tricalcium phosphate composite cement composed with polyacrylic acid (PAA-apatite/TCP) has previously been reported to be a great promise for orthopedic applications. However, it was investigated that PAA could inhibit apatite phase conversion and result in poor bioactivity. To improve those limitations, PAA-apatite/TCP cement modified with the bioactive glass nanoparticle (0–1.5 wt%) was investigated for physical properties, phase formation after setting and bioactivity. In addition, human Adipose-derived Stem/Stromal cells (hASCs), which were isolated from human adipose tissue and represent a widely implemented cell type for tissue engineering applications, were selected to determine their biological response to the bioactive glass modified PAA-apatite/TCP cement. The results indicated that the PAA-apatite/TCP cement added with bioactive glass cement decreased setting time and enhanced apatite phase transformation and bioactivity, as compared with the control cement. For in vitro testing, hASCs viability, proliferation, and differentiation potential were assessed under two cell culture conditions. In details, cells were either cultured with cement-preconditioned medium (indirect setting) or with cement (direct setting). The indirect culture presented a lower proliferation rate as compared with the control medium. In contrast, the result of direct culture indicated a higher proliferation rate on both control cement and 1 wt% bioactive glass incorporated cement, as compared with coverslip control. Moreover, the increase in Alkaline Phosphatase activity following osteogenic stimuli indicated that both cements supported osteogenic commitment. In conclusion, these in vitro data lay the basis for a deeper investigation of 1 wt% bioactive glass incorporated cement as a promising formula for clinical applications in bone engineering and orthopedics.