Objective　To investigate the effect of laboratory domestication duration on the gut microbiota of mosquitoes, reveal the patterns of intestinal microbiota changes, and more systematically elucidate the role of mosquito gut microbiota on the transmission of vector-borne pathogens and mosquito resistance to insecticides, providing new insights into the interaction between microorganisms and mosquitoes. Furthermore, to understand the composition of gut microbiota in different geographic strains of mosquitoes to serve as a reference for selecting suitable populations for subsequent functional studies of gut microbiota. Methods The full-length bacterial ribosomal 16S amplification and metagenomic sequencing were performed to reveal the midgut microbiota in 5 Aedes aegypti strains which had been domesticated in the laboratory for various years. The composition, abundance, diversity, and correlation of the microbiota carried by the 5 mosquito strains were analyzed through bioinformatics, and the content of specific bacteria that play an important role in mosquito growth and development, pathogen transmission, and insecticide resistance in different samples were compared. Results The ML and CJ strains, which had been domesticated for a shorter duration, exhibited higher diversity indices compared to the DB and SA strains, which had been bred for a longer time. The gut microbiota of all mosquitoes mainly consisted of Proteobacteria, Firmicutes, and Bacteroidota. At the genus level, the bacterial composition of Aedes aegypti MH, DB, and SA strains was relatively homogenous, predominantly consisting of Cedecea and Asaia, while the ML and CJ strains, domesticated for a shorter period, harbored a richer and more balanced variety of bacteria. Conclusions Under laboratory conditions, the diversity of mosquito gut microbiota will decrease with increased domestication duration. Bacteria that have a positive effect on mosquito growth and development tend to be retained and increase in proportion over time, while the proportion of most other bacteria will decrease or even disappear.

To study the inhibitory effect of a recombinant adenoviral vector carrying human IL-24 gene on SGC-7901 human gastric cancer cell. We infected the SGC-7901 gastric cancer cells with Ad blank adenovirus at various multiplicity of infection (MOIs) to find the optimal infective dose. The SGC-7901 tumor cells were infected with Ad-IL-24 at the optimal MOI in the following experiments. Adenovirus-mediated IL-24 transcription expression in SGC-7901 cells was examined by RT-PCR. The growth-suppressing effect of Ad-IL-24 on SGC-7901 tumor cells was assessed by MTT assay. Apoptosis and cell cycle of SGC-7901 tumor cells infected with Ad-IL-24 was evaluated by flow cytometer (FCM), respectively. The karyomorphology of apoptotic SGC-7901 tumor cells was examined using Hoechst33258 staining under fluorescence microscopy. The expression of apoptosis-related genes was future determined by semi-quantification RT-PCR; We demonstrated that the MOI of 100 was the optimal infective dose in the study on adenovirus-mediated IL-24 gene transfer into SGC-7901 gastric cancer cell; IL-24 gene mediated by adenovirus could successfully transcribe in SGC-7901 tumor cells; Ad-IL-24 could significantly inhibit SGC-7901 tumor cell growth and induce apoptosis, it also can up-regulate the express of bax, caspase-3 and p53 whilst down-regulate the bcl-2 expression. Thus, adenovirus-mediated IL-24 expression had marked anti-tumor effect in suppressing SGC-7901 human gastric cancer cell growth and inducing apoptosis, which may be closely associated with its up-regulation of bax/bcl-2, caspase-3 and p53.
Adenoviridae ; genetics ; metabolism ; Apoptosis ; genetics ; Caspase 3 ; genetics ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Interleukins ; biosynthesis ; genetics ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; Stomach Neoplasms ; genetics ; pathology ; Transfection ; Tumor Suppressor Protein p53 ; genetics ; metabolism ; Up-Regulation ; bcl-2-Associated X Protein ; genetics ; metabolism

To study the inhibitory effect and anti-cancer mechanisms of interleukin 24 (IL-24) on human osteosarcoma cell MG-63, we delivered IL-24 into MG-63 cells in vitro and in vivo by adenovirus. The expression level of IL-24 was detected by RT-PCR and fluorescence microscope; the growth inhibition, apoptosis rate and apoptosis body were measured by MTT, Flow cytometry and Hoechst staining respectively. Furthermore, we analyzed the expression of bcl-2, bax, caspase3 genes by RT-PCR after overexpression of IL-24. For in vivo study, we first established the MG-63 tumor model by grafting MG-63 cells in athymic nude mice; and then injected Ad-IL-24 into the tumors. Two weeks after injection, we sacrificed the mice, removed the tumors, weighed and calculated the ratios of tumor-suppression. We also detected the expressions of Bcl-2, Bax, Caspase-3 and CD34 with immumohistochemistry. Our in vitro results indicated that Ad-IL-24 was transcribed and translated in MG-63 osteosarcoma cells. More interestingly, IL-24 inhibited the growth of MG-63 cells and induced apoptosis by up-regulation of bax, caspase-3 and down-regulation of bcl-2. The in vivo data showed that IL-24 suppressed the tumor growth conspicuously through down-regulating the expression of bcl-2, and up-regulating the expression of bax, caspase-3. This study would provide evidence for the gene therapy of IL-24 on osteosarcoma.
Adenoviridae ; genetics ; metabolism ; Animals ; Apoptosis ; genetics ; Bone Neoplasms ; pathology ; therapy ; Caspase 3 ; metabolism ; Cell Line, Tumor ; Genetic Therapy ; Humans ; Interleukins ; biosynthesis ; genetics ; Mice ; Mice, Nude ; Osteosarcoma ; pathology ; therapy ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; bcl-2-Associated X Protein ; metabolism

Objective:To study the inhibitory effect and anti-cancer mechanisms of adenovirus-mediated ING4 gene on the MG-63 osteosarcoma xenografts in nude mice.Methods:Ad-ING4 was transfected into QBI-293 cells and harvested.15 nude mice of the subcutaneous tumor models were established with MG-63 osteosarcoma cells and were randomly divided into PBS,Ad-GFP and Ad-ING4 groups.Then PBS(100 μl),Ad-GFP(100 μl,10~9pfu/ml) and Ad-ING4 (100 μl,10~9pfu/ml) for each one were given respectively QOD for 5 times,with intratumor injections.Tumor volume changes were monitored;and the 15 mice were sacrificed 2 weeks after treatment,the tumors were removed,weighed and ratios of tumor-suppression were calculated.The morphological changes of apoptotic tumor cells were observed under microscope.Bcl-2,Bax,Caspase-3,VEGF,CD34 expression was tested by immumohistochemistry.Results:High titer(10~9pfu/ml)adenoviral vector of ING4 gene were obtained.In nude mice bearing MG-63 osteosarcoma xenografts,the growth of MG-63 tumors treated by intratumoral injecting of Ad-ING4 was significantly suppressed,compared with PBS group and Ad-GFP group.The ratios of tumor weight-suppression of Ad-ING4 group was 59.3%(P＜0.05).Immumohistochemistry displayed that the expression of Bax,Caspase-3 was up-regulated and the expression of Bcl-2,VEGF,CD34 was down-regulated by Ad-ING4.Conclusion:Ad-ING4 can inhibit the growth of MG-63 osteosarcoma xenografts in nude mice,which may be via activating the apoptosis pathway and inhibiting tumor angiogenesis.

Objective To establish Ad-hLIF transgenic feeder cells for the expansion of umbilical cord blood CD34+ HSPC in vitro and study the SCID mice model of hematopoietic stem/progenitor cell (HSPC) transplantation. Methods The expression of objective gene in Ad-hLIF transgenic feeder cells was detected by RT-PCR and ELISA. The purity of umbilical cord blood CD34+ HSPC separated by magnetic-activated cell sorting(MACS) was detected by the flow cytometry. After expanded with various combinant of cytokines and transgenic feeder layer cells for 28 d, the quantity of mono-nuclear cell (MNC) and CD34+ cells rate was detected in different time. MNC after expansion stained by CFDA SE was injected to the sublethally irradiated SCID mice. Humanize gene Alu was detected by RT-PCR and fluorescence microscope. Results The green fluorescence was observed in the transgenic cells infected with 50MOI( multiplicity of infection) Ad-hLIF, and the objective gene was confirmed by RT-PCR and ELISA. The purity of umbilical cord blood CD34+ HSPC separated by MACS could reach 95.60% ±2.58%, Ad-hLIF transgenic feeder cells and various cytokines system increased MNC by 356.95±0.87 fold, and maximal expansion of CD34+ cells was observed during 0-14 d of culture, then down-expansion gradually. Four weeks after transplanted in SCID mice, fluorescently-labeled humanize cells still can be observed. The existence of the humanized gene Alu was confirmed by RT-PCR. Conclusion Ad-hLIF transgenic feeder cells can effectively proliferate umbilical cord blood CD34+ HSPC in vitro and delay it differentiate, what's more, it has high transplant efficacy and haematogenesis activity.