No abstract

Mesenchymal stem cell (MSC)-based therapy using gene delivery systems has been suggested for degenerative diseases. Although MSC-based clinical applications are effective and safe, the mode of action remains unclear. Researchers have commonly applied viral-based gene modification because this system has efficient vehicles. While viral transfection carries many risks, such as oncogenes and chromosomal integration, nonviral gene delivery techniques are less expensive, easier to handle, and safe, although they are less efficient. The electroporation method, which uses Nucleofection technology, provides critical opportunities for hard-to-transfect primary cell lines, including MSCs. Therefore, to improve the therapeutic efficacy using genetically modified MSCs, researchers must determine the optimal conditions for the introduction of the Nucleofection technique in MSCs. Here, we suggest optimal methods for gene modification in PD-MSCs using an electroporation gene delivery system for clinical application.

The toxic effects of particulate matter have been linked to polycyclic aromatic hydrocarbons (PAHs) such as benzopyrene. PAHs are potent inducers of the aryl hydrocarbon receptor (AhR), which is an expressed nuclear receptor that senses environmental stimuli and modulates gene expression. Even though several studies have shown that the benzopyrene (BP) of chemical pollutants significantly impaired stem cell activity, the exact molecular mechanisms were not clearly elucidated. In the present study, we aimed to investigate the effects of BP on placenta-derived mesenchymal stem cells (PD-MSCs) in vitro. We found that the AhR in PD-MSCs was expressed under the treatment of BP, and its activation markedly disrupted osteogenic differentiation through the alteration of stemness activity of PD-MSCs. Moreover, BP treatment significantly reduced the proliferation activity of PD-MSCs and expression of pluripotent markers through the induction of AhR. Treatment with StemRegenin 1 (SR1), a purine derivative that antagonizes the AhR, effectively prevented BP-induced reduction of the proliferation and differentiation activity of PD-MSCs. In this study, we found that BP treatment in PD-MSCs markedly obstructs PD-MSC stemness through AhR signaling. Noteworthy, SR1-mediated MSC application will contribute to new perspectives on MSC-based therapies for air pollution-related bone diseases.

Background Conventional cytogenetic analysis using G-band karyotyping has been the method of choice for prenatal diagnosis, accurately detecting chromosomal abnormalities larger than 5 Mb. However, the method is inefficient for detecting the submicroscopic deletions and duplications that are associated with malformations and mental retardation. This study evaluated the results of the multiplex ligation-dependent probe amplification (MLPA) P245 assay used for prenatal diagnosis in cases with unusual ultrasonographic findings or specifically where parents wanted to be tested. The objective was to compare the results from MLPA with those from conventional cytogenetic testing in order to determine their concordance and the additional diagnostic yield of MLPA over G-band karyotyping. Results Of the 7522 prenatal cases analyzed, 124 were found to have genomic imbalances (1.6%). Of those 124 cases, 41 had gene loss (33.6%), and 83 had gene gain (66.4%). Most of the cases with genomic imbalances (64.5%) showed no abnormal karyotype. In particular, all cases with a 4p16.3 deletion (Wolf-Hirschhorn syndrome) showed an abnormal karyotype, whereas all of those with a 22q11–13 deletion showed a normal karyotype. In most of the cases with pathogenic deletions, the indication for invasive prenatal testing was an increase in the nuchal translucency (NT) alone (51.2%). Other indications observed in the remaining cases were abnormal serum screening markers (14.6%), other ultrasonographic findings (9.8%), pregnancy through in vitro fertilization and fertility assistance (9.8%), and advanced maternal age(2.4%). Conclusions These results show that for fetuses with an enlarged NT or abnormal ultrasonographic findings and normal conventional karyotype, additional genetic investigation like molecular testing would be for identifying the microscopic genomic aberrations (microdeletions, microduplications) responsible for syndromic associations including structural anomalies and mental retardation.

No abstract