Biogenic gas vesicles labeled bone marrow mesenchymal stem cells: from synthesis to ultrasound imaging and tracking / 中华核医学与分子影像杂志

ABSTRACT

Objective:To fabricate biogenic gas vesicles (GVs)- polyethyleneimine (PEI)-marrow mesenchymal stem cells (BMSCs) and evaluate its potential on stem cell tracking with ultrasound imaging.Methods:GVs were cationized by PEI to fabricate GVs-PEI. The diameter and zeta potential of GVs-PEI were determined. GVs-PEI were co-incubated with BMSCs to obtain GVs-PEI-BMSCs and stem cell uptake was observed by fluorescence microscope. The cell viability of GVs-PEI-BMSCs was verified by cell counting kit-8 (CCK-8) assay were set. Ultrasound imaging was performed on 0, 2, 4 and 6 d in agarose phantom to evaluate ultrasound imaging capability of GVs-PEI-BMSCs group and BMSCs group in vitro. GVs-PEI-BMSCs and BMSCs were injected into quadriceps femoris of SD rats, and ultrasound imaging was performed on 0, 2, 4 and 6 d to evaluate the ultrasound imaging capability in vivo. One-way analysis of variance and independent-sample t test were used to analyze the data. Results:The diameter and zeta potential of GVs-PEI were (383.63±11.55) nm and (18.48±2.20) mV. Plenty of GVs-PEI were observed in GVs-PEI-BMSCs through microscope. When BMSCs were incubated with GVs-PEI in absorbance ( A) 500 nm of 0.5 and 1.0, there were no significant changes in the cell viability of GVs-PEI-BMSCs at 24, 48 and 72 h ( F values 7.078-11.982, all P>0.05). Compared with BMSCs, GVs-PEI-BMSCs showed better ultrasound imaging capability in vitro in all time points with still significantly different signal at 6 d (634.29±10.78 vs 2 864.51±100.86; t=-121.86, P<0.001). The ultrasound imaging capability of GVs-PEI-BMSCs in vivo was much better than that of BMSCs at each time point with still significantly different signal at 6 d (2 108.02±217.96 vs 267.71±7.87; t=-121.39, P<0.001). Conclusion:GVs-PEI-BMSCs are successfully fabricated with the advantages of significant ultrasound imaging capability, long duration and safety, which provide a brand-new means for stem cells tracking in vivo.