Biocompatibility of adipose-derived stem cells and polypropylene mesh

Abstract

Objective To investigate the biocompatibility of adipose- derived stem cells (ADSC) and polypropylene mesh in vitro and in vivo. Methods The rabbit ADSC suspension was prepared, and identified by flow cytometry. The polypropylene mesh extract was used to culture ADSC. MTT assay was used to determine the cell viability in the 24, 48, 72 h experimental groups (polypropylene mesh extract) , negative control group (10% FBS of low glucose DMEM) , and positive control group (6.4% phenol solution) , and evaluate the scaffold cytotoxicity. After passaged and amplified, ADSC were inoculated on polypropylene mesh scaffold for 1-week in vitro culture. The growth and proliferation of ADSC on the scaffold were determined by scanning electron microscope. The polypropylene mesh and ADSC- polypropylene mesh were transplanted in the surface of rabbit rectus abdominis, and the mesh corrosion and adhesion were determined at 4 weeks. Hematoxylin-eosin (HE) staining was used for histological test. RT-PCR was used to dynamically measure the expression levels of VEGF mRNA in tissues surrounding the mesh. Results The ADSC CD90, CD44 and CD73 (98.54%, 95.32%, 98.49%) were strongly positive expressed, and CD45, CD34 and CD14 (1.21% , 3.01% , 2.14% ) were low expressed. The ADSC could maintain a high proliferation rate in the polypropylene mesh extract. The relative proliferation rate in the 24, 48 and 72 h experimental groups were (97.0±12.5)%, (96.0±10.3)%, and (101.0±22.8)%, respectively. There were no statistically significant differences between the experimental groups and the negative control group (all P> 0.05). There were statistically significant differences between the experimental groups and the positive control group (all P<0.05). No cytotoxicity was found in polypropylene mesh extract. ADSC grew fast after transplanted in the two kinds of scaffold. Both of the polypropylene mesh and ADSC-polypropylene mesh had different degrees of corrosion and adhesion, whereas the polypropylene mesh adhered more tightly. Compared with the polypropylene mesh, ADSC - polypropylene mesh showed mild - induced chronic inflammatory response, low score of inflammatory response [0.6 (0.3, 0.9) vs 1.1 (0.9, 1.4) , P=0.001] , and higher scores of neovascularization [2.6 (2.1, 3.1) vs 1.7 (1.2, 2.1) , P=0.000] and fibroblastic proliferation [2.2 (0.9, 2.6) vs 0.9 (0.6, 1.5) , P=0.001]. The VEGF mRNA content in the surrounding tissues of the ADSC- polypropylene mesh (1.53±0.11) was higher than that of the polypropylene mesh (0.96±0.05) (t=11.005, P< 0.05). Conclusion Polypropylene mesh scaffold and ADSC show good biocompatibility, which can be used as an ideal biological scaffold material for adipose tissue engineering. Key words: Adipose-derived stem cells; Polypropylene mesh; Biocompatibility