OBJECTIVE: To prepare decellularized nerve grafts from alpha-1, 3-galactosyltransferase (GGTA1) gene-edited pigs and explore their biocompatibility for xenotransplantation. METHODS: The sciatic nerves from wild-type pigs and GGTA1 gene-edited pigs were obtained and underwent decellularization. The alpha-galactosidase (α-gal) content in the sciatic nerves of GGTA1 gene-edited pigs was detected by using IB4 fluorescence staining and ELISA method to verify the knockout status of the GGTA1 gene, and using human sciatic nerve as a control. HE staining and scanning electron microscopy observation were used to observe the structure of the nerve samples. Immunofluorescence staining and DNA content determination were used to evaluate the degree of decellularization of the nerve samples. Fourteen nude mice were taken, and subcutaneous capsules were prepared on both sides of the spine. Decellularized nerve samples of wild-type pigs ( n=7) and GGTA1 gene-edited pigs ( n=7) were randomly implanted in the subcutaneous capsules. Blood was drawn at 1, 3, 5, and 7 days after implantation to detect neutrophil counting. RESULTS: IB4 fluorescence staining and ELISA detection showed that GGTA1 gene was successfully knocked out in the nerves of GGTA1 gene-edited pigs. HE staining showed that the structure of the decellularized nerve from GGTA1 gene-edited pigs was well preserved; the nerve basement membrane tube structure was visible under scanning electron microscopy; no cell nuclei was observed, and the extracellular matrix components was retained in the nerve grafts by immunofluorescence staining; and the DNA content was significantly reduced when compared with the normal nerves ( P<0.05). In vivo experiments showed that the number of neutrophils in the two groups were similar at 1, 3, and 7 days after implantation, with no significant difference ( P>0.05); only at 5 days, the number of neutrophils was significantly lower in the GGTA1 gene-edited pigs than in the wild-type pigs ( P<0.05). CONCLUSION The decellularized nerve grafts from GGTA1 gene-edited pigs have well-preserved nerve structure, complete decellularization, retain the natural nerve basement membrane tube structure and components, and low immune response after xenotransplantation through in vitro experiments.
Animals ; Transplantation, Heterologous ; Galactosyltransferases/genetics* ; Sciatic Nerve/immunology* ; Swine ; Tissue Engineering/methods* ; Humans ; Graft Rejection/prevention & control* ; Gene Editing ; Mice ; Mice, Nude ; Heterografts/immunology* ; Animals, Genetically Modified ; Tissue Scaffolds ; Decellularized Extracellular Matrix

OBJECTIVES: Multiple myeloma (MM) is a plasma cell malignancy occurring in middle and old age. MM is still an incurable disease due to its frequent recurrence and drug resistance. However, its pathogenesis is still unclear. Abnormal amino acid metabolism is one of the important characteristics of MM, and the important metabolic pathway of amino acids participates in protein synthesis as basic raw materials. Aminoacyl transfer ribonucleic acid synthetase (ARS) gene is a key regulatory gene in protein synthesis. This study aims to explore the molecular mechanism for ARS, a key factor of amino acid metabolism, in regulating amino acid metabolism in MM and affecting MM growth. METHODS: The corresponding gene number was combined with the gene expression profile GSE5900 dataset and GSE2658 dataset in Gene Expression Omnibus (GEO) database to standardize the gene expression data of ARS. GSEA_4.2.0 software was used to analyze the difference of gene enrichment between healthy donors (HD) and MM patients in GEO database. GraphPad Prism 7 was used to draw heat maps and perform data analysis. Kaplan-Meier and Cox regression model were used to analyze the expression of ARS gene and the prognosis of MM patients, respectively. Bone marrow samples from 7 newly diagnosed MM patients were collected, CD138⁺ and CD138^- cells were obtained by using CD138 antibody magnetic beads, and the expression of ARS in MM clinical samples was analyzed by real-time RT-PCR. Human B lymphocyte GM12878 cells and human MM cell lines ARP1, NCI-H929, OCI-MY5, U266, RPMI 8266, OPM-2, JJN-3, KMS11, MM1.s cells were selected as the study objects. The expression of ARS in MM cell lines was analyzed by real-time RT-PCR and Western blotting. Short hairpin RNA (shRNA) lentiviruses were used to construct gene knock-out plasmids (VARS-sh group). No-load plasmids (scramble group) and gene knock-out plasmids (VARS-sh group) were transfected into HEK 293T cells with for virus packaging, respectively. Stable expression cell lines were established by infecting ARP1 and OCI-MY5 cells, and the effects of knockout valyl-tRNA synthetase (VARS) gene on proliferation and apoptosis of MM cells were detected by cell counting and flow cytometry, respectively. GEO data were divided into a high expression group and a low expression group according to the expression of VARS. Bioinformatics analysis was performed to explore the downstream pathways affected by VARS. Gas chromatography time-of-flight mass spectrometry (GC-TOF/MS) and high performance liquid chromatography (HPLC) were used to detect the valine content in CD138⁺ cells and ARP1, OCI-MY5 cells and supernatant of knockdown VARS gene in bone marrow samples from patients, respectively. RESULTS: Gene enrichment analysis showed that tRNA processing related genes were significantly enriched in MM compared with HD (P<0.0001). Further screening of tRNA processing-pathway related subsets revealed that cytoplasmic aminoacyl tRNA synthetase family genes were significantly enriched in MM (P<0.0001). The results of gene expression heat map showed that the ARS family genes except alanyl-tRNA synthetase (AARS), arginyl-tRNA synthetase (RARS), seryl-tRNA synthetase (SARS) in GEO data were highly expressed in MM (all P<0.01). With the development of monoclonal gammopathy of undetermined significance (MGUS) to MM, the gene expression level was increased gradually. Kaplan-Meier univariate analysis of survival results showed that there were significant differences in the prognosis of MM patients in methionyl-tRNA synthetase (MARS), asparaginyl-tRNA synthetase (NARS) and VARS between the high expression group and the low expression group (all P<0.05). Cox regression model multivariate analysis showed that the high expression of VARS was associated with abnormal overall survival time of MM (HR=1.83, 95% CI 1.10 to 3.06, P=0.021). The high expression of NARS (HR=0.90, 95% CI 0.34 to 2.38) and MARS (HR=1.59, 95% CI 0.73 to 3.50) had no effect on the overall survival time of MM patients (both P>0.05). Real-time RT-PCR and Western blotting showed that VARS, MARS and NARS were highly expressed in CD138⁺ MM cells and MM cell lines of clinical patients (all P<0.05). Cell counting and flow cytometry results showed that the proliferation of MM cells by knockout VARS was significantly inhibited (P<0.01), the proportion of apoptosis was significantly increased (P<0.05). Bioinformatics analysis showed that in addition to several pathways including the cell cycle regulated by VARS, the valine, leucine and isoleucine catabolic pathways were upregulated. Non-targeted metabolomics data showed reduced valine content in CD138⁺ tumor cells in MM patients compared to HD (P<0.05). HPLC results showed that compared with the scramble group, the intracellular and medium supernatant content of ARP1 cells and the medium supernatant of OCI-MY5 in the VARS-shRNA group was increased (all P<0.05). CONCLUSIONS MM patients with abnormal high expression of VARS have a poor prognosis. VARS promotes the malignant growth of MM cells by affecting the regulation of valine metabolism.
Humans ; Valine-tRNA Ligase ; Multiple Myeloma/genetics* ; Metabolomics ; Amino Acids ; RNA, Transfer

Objective To evaluate the cost-utility of different hepatitis E vaccination strategies in women aged 15 to 49.Methods The Markov-decision tree model was constructed to evaluate the cost-utility of three hepatitis E virus vaccination strategies.Parameters of the models were estimated on the basis of published studies and experience of experts.Both methods on sensitivity and threshold analysis were used to evaluate the uncertainties of the model.Results Compared with non-vaccination group,strategy on post-screening vaccination with rate as 100％,could save 0.10 quality-adjusted life years per capital in the women from the societal perspectives.After implementation of screening program and with the vaccination rate reaching 100％,the incremental cost utility ratio (ICUR) of vaccination appeared as 5 651.89 and 6 385.33 YuaWQALY,respectively.Vaccination post to the implementation of a screening program,the result showed better benefit than the vaccination rate of 100％.Results from the sensitivity analysis showed that both the cost of hepatitis E vaccine and the inoculation compliance rate presented significant effects.If the cost were lower than 191.56 Yuan (RMB) or the inoculation compliance rate lower than 0.23,the vaccination rate of 100％ strategy was better than the post-screening vaccination strategy,otherwise the post-screening vaccination strategy appeared the optimal strategy.Conclusion Post-screening vaccination for women aged 15 to 49 from social perspectives seemed the optimal one but it had to depend on the change of vaccine cost and the rate of inoculation compliance.

AIM: Our study focused on investigation of tissue specific regulatory activity of the newly cloned promoter: PLUNC-p with driving enhanced green fluorescent protein ( EGFP ). METHODS: Transgenic Xenopus Laevis system was applied.RESULTS: The green fluorescence protein directed under PLUNC-p was expressed strictly in branchial arches and epidermis of Xenopus Laevis embryos while CMV promoter showed ubiquitous regulation characteristic.CONCLUSION: PLUNC-p is able to direct epithelia specific expression of EGFP . This property of PLUNC-p might raise the possibility that lead target genes to express tissue-specifically.

The extract content and in vitro releasing content from different processed products of Squama Manitis were determined using protein as index.The result indicates that the releasing rate of both pro- eessed products are obviously higher than that of the crude.The in vitro study on releasing rate of the same processed product shows that the dissolving rate in vitro has tight relation to its particle size.