Biomedical subjects

Hongyang Zhao

Publications and source records attributed to Hongyang Zhao.

6 recordsLinked to original sources

PubMed2026

Induced pluripotent stem cell reprogramming: methodological evolution and challenges in clinical translation.

Cell reprogramming can transform somatic cells into induced pluripotent stem cells providing a platform for patient-specific disease modeling, drug screening and regenerative medicine research. Since the advent of OKSM-mediated reprogramming, the system of technical approaches has evolved continuously - from integrated viral vectors to non-integrated episomal systems and, more recently, chemical reprogramming and CRISPR approaches. The simultaneous advances in single-cell multi-omics, biomaterials engineering, and artificial intelligence have further refined the controllability and precision of the reprogramming process. Despite these innovations, problems persist that hinder clinical translation: incomplete epigenetic resetting, ongoing clonal heterogeneity, genomic instability in long-term culture, and the lack of standardized Good Manufacturing Practice protocols for large-scale manufacturing. This review summarizes the trajectory of iPSC reprogramming technologies, with special emphasis on the translational applicability of each modality. We evaluated viral and nonviral delivery systems, chemical reprogramming, strategies that aid gene editing, and emerging engineering platforms, including microfluidics, smart biomaterials, and artificial-intelligence-driven process optimization. We further identify the core "translational triltrilas", namely, the inherent tradeoffs between security, homogeneity, and scalability, and propose a comprehensive strategy to overcome these bottlenecks. By linking basic mechanistic understandings with industrial and regulatory considerations, this review aims to provide a route for transitioning iPSC technology from a laboratory tool to a clinically viable manufacturing platform.

clinical translation↗

PubMed2006

Magnetic resonance imaging of transplanted neural stem cells in Parkinson disease rats.

In this study we implanted magnetically labeled neural stem cells (NSCs) in PD rats and then monitored their survival and migration in the host brain by magnetic resonance imaging (MRI). The mesencephalic NSCs were obtained from the brain of SD rats. Superparamagnetic iron oxide (SPIO) was transferred to NSCs by Lipofectamine transfection. Eighteen PD lesioned rats were selected for transplantation by evaluation of their rotational behavior in response to amphetamine and randomly assigned to 3 groups, i.e., sham group, PBS group and NSCs transplanted group, with 6 rats in each group. MR scanning was performed at 1, 2, 4, 6, 8 and 10 week(s) following transplantation. At the meantime, rotational behavior was assessed in each group. Our results showed that SPIO particles were clearly visible with Prissian blue staining in neurospheres and cells derived from NSCs. The rotational behavior of the NSCs transplanted group was remarkably improved compared with that of sham group and PBS group (P < 0.05). In vivo MR tracking of NSCs showed that SPIO labeling led to a strong susceptibility change of signal 1 week after transplantation on T2 weighted images. And a large circular hypointense signal appeared in the transplanted area on T2* gradient echo images. Ten weeks following transplantation, the hypointense signal on T2 weighted and T2* gradient echo images was still displayed. It is concluded that SPIO particles could label NSCs effectively, and MRI detection of SPIO labeled cells is a promising method and novel approach to analyzing the NSCs following transplantation in the treatment of PD.

Animals↗

PubMed2005

Effect of wild-type p53 gene transfection on the growth and radiotherapeutic sensitivity of human glioma cells.

To evaluate the effect of wild-type p53 gene on the growth and radiotherapeutic sensitivity of human glioma cells, plasmid PC53-SN3 carrying wild-type p53 gene was transfected into U251 cells. p53 gene expression in transfected cells was detected by RT-PCR, and the cell growth inhibition and apoptosis in the absence or presence of irradiation were assessed by MTT and flow cytometry. The transfection of p53 gene into U251 cells was confirmed by RT-PCR. MTT showed that p53 gene alone induced strong inhibitory effect on the growth of U251 cells (inhibition rate (IR), (79.60 +/- 5.69)%). The killing effect of irradiation alone on U251 cells was not strong (IR: (17.06 +/- 4.35)% (17.39 +/- 1.67)% (18.73 +/- 4.68)%) and increased with the irradiation doses (3, 6, 9 Gy). When combined treatment of wild-type p53 gene transfection and irradiation was used, the effect was significantly increased (IR:(80.60 +/- 5.35)%. (90.30 +/- 1.67)%, (91.30 +/- 2.01)%). The apoptosis rate of U251 cells induced by p53 gene transfection was 17.38%. The rate induced by irradiation increased (4.61%, 4.84%, 5.40%) with the irradiation doses (3, 6, 9 Gy). The apoptosis rate was also significantly increased (17.80%, 20.03%, 22.34%) after combined treatment of p53 and irradiation with different doses (3, 6, 9 Gy). It is concluded that wild-type p53 gene and irradiation could result in synergistic inhibitory effect on the growth of human glioma cells.

Apoptosis↗

PubMed2004

Anti-angiogenesis effect on glioma of attenuated Salmonella typhimurium vaccine strain with flk-1 gene.

To investigate the anti-vasculature effects and the anti-glioma effects of attenuated Salmonella typhimurium vaccine strain expressing VEGFR2 (flk-1) gene, plasmid pcDNA3.1-flk1 was constructed and electro-transfected into live attenuated Salmonella typhimurium strain SL7207. Mouse models of intracranial G1261 glioblastoma were treated with an orally administered attenuated Salmonella typhimurium expressing flk-1 gene. The survival period was recorded and vessel density was observed by immunofluorescence. CTLs activity was measured by MTT assay. Our results showed that attenuated Salmonella typhimurium vaccine strain expressing flk-1 gene could significantly inhibit glioblastoma growth, reduce vessel density, prolong the survival period and improve the survival rate in these mice. The flk-1 specific CTLs activity was increased obviously after the vaccination. Our study showed that attenuated Salmonella typhimurium vaccine strain expressing flk-1 gene could break peripheral immune tolerance a in glioma gainst this self-antigen and kill endothelial cells by the orally administered vaccine and can be used for both prophylactic and therapeutic purposes.

Angiogenesis Inhibitors↗

PubMed2002

The effects of wild-type p53 gene transfection on the growth and chemotherapeutic sensitivity of human glioma cells.

To evaluate the effects of wild-type p53 gene on the growth and chemotherapeutic sensitivity of human glioma cells, plasmid PC53-SN3 carrying wild-type p53 gene was transfected into U251 cells. p53 gene expression in transfected cells was detected by RT-PCR, the cell growth inhibition and apoptosis in either the absence or the presence of cisplatin was assessed by MTT and flow cytometry. The transfection of p53 gene into U251 cells was confirmed by RT-PCR. MTT showed that p53 gene by itself induced strong inhibition effect on the growth of U251 cells [inhibition rate, IR (79.60 +/- 5.69)%]. The killing effects of cisplatin by itself on U251 cells was not strong [IR (19.40 +/- 6.69)%, (24.41 +/- 2.68)%, (51.84 +/- 13.38)%, (66.22 +/- 5.02)%] and increased with the increase of cisplatin concentration (1, 2, 4, 8 micrograms/ml). When combined treatment of wild-type p53 gene transfection and cisplatin was used, that was significantly increased [IR (91.64 +/- 1.00)%, (94.98 +/- 1.67)%, (95.32 +/- 2.01)%, (95.65 +/- 1.00)%]. The apoptosis rate of U251 cells induced by p53 gene transfection was 17.38%. That induced by cisplatin increased (5.71%, 5.93%, 6.27%, and 6.81%) with the increase of cisplatin concentration (1, 2, 4, 8 micrograms/ml). The apoptosis rate was also significantly increased (23.50%, 23.54%, 23.89%, and 28.88%) after combined treatment of p53 and cisplatin with different concentration (1, 2, 4, 8 micrograms/ml). It is concluded that wild-type p53 gene and cisplatin could result in synergistic inhibition effects on the growth of human glioma cells.

Antineoplastic Agents↗

PubMed2002

[Effect of soil compaction on Vicia faba of growth in the Loess Plateau].

The effect of soil compaction on the growth of Vicia faba was studied by pot experiment, field plot experiment, and farmers' field production during two consecutive years. The results showed that increasing soil bulk density at 0-7 cm depth significantly decreased the root and shoot dry weight per plant, increased plant mortality caused by Fusarium species, and decreased seed yields. Field experiments indicated that compared to the plants grown on the plots with soil bulk density of 1.55 and 1.64 g.cm-3, the root and shoot dry weight of plants grown on the plots with soil bulk density of 1.84 g.cm-3 decreased by 30.8% and 27.9%, respectively, while the plant mortality rate increased by 21.0-48.7%, and seed yields decreased by 19.8%. The trials conducted on eight farmers' land illustrated that there existed significant negative correlations between soil bulk density in Spring and root and shoot dry weight of Vicia faba seedlings, and between soil bulk density in Autumn and seed yields. The causes of high soil compaction were discussed, and suggestions for improving soil quality were presented.

China↗