Alwan Abdelrahman, Khalil Fatma, Bowlby Joshua, Peko Gabrielle, Estrada Exel Valle, Singh Sangeeta, Deep Gagan, Zhang Yuanyuan, Farney Alan C, Opara Emmanuel C
Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, United States.
Department of Histology, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt.
Front Bioeng Biotechnol. 2024 Aug 21;12:1436296. doi: 10.3389/fbioe.2024.1436296. eCollection 2024.
The hepatic growth factor (HGF) stimulates DNA synthesis and cell proliferation and plays a role in tissue protection and regeneration. In this study, we have examined the effect of incubation of HGF with urine-derived stem cells (USCs) on the secretion of small extracellular vesicles (sEV) by the cells.
HGF in the incubation medium was either a bolus administration or a controlled release of an equivalent amount from microbeads within the size range of 50-200 µm made with ultrapurified low-viscosity high-guluronic acid (UP-LVG) alginate. USCs were incubated with or without HGF for 3 days or 7 days before removal of the incubation media, followed by harvesting sEV by the precipitation method. The protein content of isolated sEV was measured by bicinchoninic acid assay (BCA) for these three groups: control (no HGF beads), bolus HGF, and HGF beads. We also performed nanoparticle tracking analysis (NTA), Western blot assay, and ELISA for the HGF content of samples.
We found a significantly higher concentration of proteins in the HGF microbead group (control release group) compared to the bolus group and the control group after 7 days ( < 0.0017). The NTA data aligned with the BCA; they showed a significantly higher concentration of particles within the size range of sEV (<200 nm) in the group treated with HGF beads compared to the two other groups on day 7 ( < 0.0001).
We found that administration of HGF to USCs by controlled release of the growth factor significantly enhances the levels of sEV secretion during 7 days of incubation.
肝细胞生长因子（HGF）可刺激DNA合成和细胞增殖，并在组织保护和再生中发挥作用。在本研究中，我们检测了HGF与尿源干细胞（USCs）共孵育对细胞分泌小细胞外囊泡（sEV）的影响。
孵育培养基中的HGF采用一次性给药，或由超纯低粘度高古洛糖醛酸（UP-LVG）海藻酸盐制成的50-200 µm大小范围内的微珠控释等量HGF。在去除孵育培养基之前，将USCs与有或无HGF共孵育3天或7天，然后通过沉淀法收集sEV。采用二喹啉甲酸测定法（BCA）测量这三组分离的sEV的蛋白质含量：对照组（无HGF微珠）、一次性给予HGF组和HGF微珠组。我们还对样品的HGF含量进行了纳米颗粒跟踪分析（NTA）、蛋白质免疫印迹分析和酶联免疫吸附测定（ELISA）。
我们发现，7天后，HGF微珠组（控释组）的蛋白质浓度明显高于一次性给药组和对照组（<0.0017）。NTA数据与BCA结果一致；它们显示，与另外两组相比，在第7天，用HGF微珠处理的组中，sEV大小范围内（<200 nm）的颗粒浓度明显更高（<0.0001）。
我们发现，通过生长因子控释向USCs给药HGF可在7天的孵育期内显著提高sEV的分泌水平。
