Efficient derivation of extended pluripotent stem cells from NOD-scid Il2rg mice

Recently we have established a new culture condition enabling the derivation of extended pluripotent stem (EPS) cells, which, compared to conventional pluripotent stem cells, possess superior developmental potential and germline competence. However, it remains unclear whether this condition permits derivation of EPS cells from mouse strains that are refractory or non-permissive to pluripotent cell establishment. Here, we show that EPS cells can be robustly generated from non-permissive NOD-scid Il2rg mice through de novo derivation from blastocysts. Furthermore, these cells can also be efficiently generated by chemical reprogramming from embryonic NOD-scid Il2rg fibroblasts. NOD-scid Il2rg EPS cells can be expanded for more than 20 passages with genomic stability and can be genetically modified through gene targeting. Notably, these cells contribute to both embryonic and extraembryonic lineages in vivo. More importantly, they can produce chimeras and integrate into the E13.5 genital ridge. Our study demonstrates the feasibility of generating EPS cells from refractory mouse strains, which could potentially be a general strategy for deriving mouse pluripotent cells. The generation of NOD-scid Il2rg EPS cell lines permits sophisticated genetic modification in NOD-scid Il2rg mice, which may greatly advance the optimization of humanized mouse models for biomedical applications.

Rapid generation of gene-targeted EPS-derived mouse models through tetraploid complementation

One major strategy to generate genetically modified mouse models is gene targeting in mouse embryonic stem (ES) cells, which is used to produce gene-targeted mice for wide applications in biomedicine. However, a major bottleneck in this approach is that the robustness of germline transmission of gene-targeted ES cells can be significantly reduced by their genetic and epigenetic instability after long-term culturing, which impairs the efficiency and robustness of mouse model generation. Recently, we have established a new type of pluripotent cells termed extended pluripotent stem (EPS) cells, which have superior developmental potency and robust germline competence compared to conventional mouse ES cells. In this study, we demonstrate that mouse EPS cells well maintain developmental potency and genetic stability after long-term passage. Based on gene targeting in mouse EPS cells, we established a new approach to directly and rapidly generate gene-targeted mouse models through tetraploid complementation, which could be accomplished in approximately 2 months. Importantly, using this approach, we successfully constructed mouse models in which the human interleukin 3 (IL3) or interleukin 6 (IL6) gene was knocked into its corresponding locus in the mouse genome. Our study demonstrates the feasibility of using mouse EPS cells to rapidly generate mouse models by gene targeting, which have great application potential in biomedical research.

Correction to: Efficient derivation of extended pluripotent stem cells from NOD-scid Il2rg mice

In the original publication Fig. 1D and supplementary material is incorrect. The correct figure and supplementary material is provided in this correction.

Differences in expression profiles of circular RNA between luminal breast cancer cells and normal breast cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the differences in the expression profiles of circular RNA (circRNA) between luminal breast cancer cells and normal breast cells.</p><p><b>METHODS</b>Total RNA extracted from luminal breast cancer cells MCF7 and normal breast cells MCF10A was digested with Rnase R to remove linear RNAs and enrich circRNAs. The enriched circRNAs were amplified and transcribed into fluorescent cRNAs using a random priming method, and were hybridized onto the circRNA hybridization array. The circRNA expression profiles of MCF7 and MCF10A cells were analyzed using Agilent Feature Extraction software. Quantile normalization and subsequent data processing were performed, and volcano plot filtering and hierarchical clustering were utilized to analyze the circRNA expression patterns. The expressions of 3 circRNAs with significant log fold changes were validated using qPCR.</p><p><b>RESULTS</b>The hybridization array data revealed significant differences in the circRNA expression profiles between MCF7 and MCF10A cells. Compared with those of MCF10A cells, the 12910 circRNAs expressed in MCF7 cells showed 5964 up-regulated, 81 consistently regulated, and 6865 down-regulated circRNAs; 343 circRNAs showed a log fold change by more than 2 folds, among which 213 circRNAs were up-regulated and 130 were down-regulated. Nine circRNAs showed differential expressions by more than 2 folds, including 8 up-regulated ones, namely hsa_circRNA_061260 (6.02 folds), hsa_circRNA_103933 (5.96 folds), hsa_circRNA_005239 (5.84 folds), hsa_circRNA_100689 (5.69 folds), hsa_circRNA_004087 (5.60 folds), hsa_circRNA_104420 (5.25 folds), hsa_circRNA_104421 (5.13 folds) and hsa_circRNA_101222 (5.03 folds); only one circRNA was down-regulated, namely hsa_circRNA_104864 (5.09 folds). The expressions of hsa_circRNA_100689, hsa_circRNA_005239 and hsa_circRNA_104864 were further validated by qPCR, which yielded consistent results with the microarray data.</p><p><b>CONCLUSIONS</b>The circRNA expression profiles differ significantly between luminal breast cancer cells and normal breast cells. These differentially expressed circRNAs may serve as potential novel targets for the diagnosis of luminal breast cancer.</p>

The treatment of cerebrospinal fluid rhinorrhea:a report of 82 cases / 中国微创外科杂志

Objective To summarize our experience in managing cerebrospinal fluid(CSF) rhinorrhea. Methods 82 cases of cerebrospinal fluid rhinorrhea treated in our department from 1995 to 1999 were reviewed retrospectively. 61 were male and 21 were female.They ranged from 2 to 82 years old.CSF leak was caused by trauma in 43 cases,iatrogenic injury in 18 cases and spontaneous leak occurred in 21 cases. Results 36 cases underwent surgical repair.The closure rate was 86 11%.Otorhinolaryngologists underwent 25 cases,and 23 cases succeeded (92%).The department of neurology underwent 11 cases,and 8 cases succeeded (72 7%). Conclusions The repair of CSF leak through transnasal extracranial approach can obtain better therapeutic results,especially through intranasal endoscopy.