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71.
Daisuke S. Yamamoto Megumi Sumitani Katsumi Kasashima Hideki Sezutsu Hiroyuki Matsuoka 《PLoS pathogens》2016,12(9)
Malaria is an important global public health challenge, and is transmitted by anopheline mosquitoes during blood feeding. Mosquito vector control is one of the most effective methods to control malaria, and population replacement with genetically engineered mosquitoes to block its transmission is expected to become a new vector control strategy. The salivary glands are an effective target tissue for the expression of molecules that kill or inactivate malaria parasites. Moreover, salivary gland cells express a large number of molecules that facilitate blood feeding and parasite transmission to hosts. In the present study, we adapted a functional deficiency system in specific tissues by inducing cell death using the mouse Bcl-2-associated X protein (Bax) to the Asian malaria vector mosquito, Anopheles stephensi. We applied this technique to salivary gland cells, and produced a transgenic strain containing extremely low amounts of saliva. Although probing times for feeding on mice were longer in transgenic mosquitoes than in wild-type mosquitoes, transgenic mosquitoes still successfully ingested blood. Transgenic mosquitoes also exhibited a significant reduction in oocyst formation in the midgut in a rodent malaria model. These results indicate that mosquito saliva plays an important role in malaria infection in the midgut of anopheline mosquitoes. The dysfunction in the salivary glands enabled the inhibition of malaria transmission from hosts to mosquito midguts. Therefore, salivary components have potential in the development of new drugs or genetically engineered mosquitoes for malaria control. 相似文献
72.
Keiko Yasuma Jun-ichirou Yasunaga Keiko Takemoto Kenji Sugata Yuichi Mitobe Norihiro Takenouchi Masanori Nakagawa Yutaka Suzuki Masao Matsuoka 《PLoS pathogens》2016,12(1)
Human T-cell leukemia virus type 1 (HTLV-1) infects CD4+ T cells and induces proliferation of infected cells in vivo, which leads to the onset of adult T-cell leukemia (ATL) in some infected individuals. The HTLV-1 bZIP factor (HBZ) gene, which is encoded in the minus strand of HTLV-1, plays critical roles in pathogenesis. In this study, RNA-seq and ChIP-seq analyses using HBZ transduced T cells revealed that HBZ upregulates the expression and promoter acetylation levels of a co-inhibitory molecule, T cell immunoglobulin and ITIM domain (TIGIT), in addition to those of regulatory T cells related genes, Foxp3 and Ccr4. TIGIT was expressed on CD4+ T cells from HBZ-transgenic (HBZ-Tg) mice, and on ATL cells and HTLV-1 infected CD4+ T cells of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in vivo. Expression of Blimp1 and IL-10 was upregulated in TIGIT+CD4+ cells of HBZ-Tg mice compared with TIGIT-CD4+ T cells, suggesting the correlation between TIGIT expression and IL-10 production. When CD4+ T cells from HBZ-Tg mice were stimulated with TIGIT’s ligand, CD155, their production of the inhibitory cytokine IL-10 was enhanced. Furthermore, dendritic cells from HBZ-Tg mice produced high levels of IL-10 after stimulation. These data suggest that HBZ alters immune system to suppressive state via TIGIT and IL-10. Importantly, TIGIT suppressed T-cell responses to another HTLV-1 virus protein, Tax, in vitro. Blocking of TIGIT and PD-1 slightly increased anti-Tax T-cell activity in some HAM/TSP patients. These results suggest that HBZ-induced TIGIT on HTLV-1 infected cells impairs T-cell responses to viral antigens. This study shows that HBZ-induced TIGIT plays a pivotal role in attenuating host immune responses and shaping a microenvironment favorable to HTLV-1. 相似文献
73.
Mikako Saito Asako Kaneda Hajime Shigeto Nobuaki Hanata Keiko Otokuni Hideaki Matsuoka 《Cytotechnology》2016,68(4):987-998
In order to produce insulin-secreting cells with a high value of glucose-stimulated insulin secretion (GSIS) from mouse embryonic stem cells, we have developed an optimized 5-stage protocol by referring to culture conditions so far reported elsewhere. This protocol is characterized by 4 points: (1) use of an activin-free medium in the first stage, (2) use of gelatin/fibronectin coated culture dishes in 1–4 stages throughout, (3) removal of undifferentiated cells by cell sorter at the end of 4th stage, and (4) sedimental culture in the 5th stage. GSIS value of the produced cells reached 2.4, that was at a higher rank of those so far reported. The produced cells were transplanted in diabetes model mice but no remedy effect was observed. Then transplantation was conducted in pre-diabetes model mice, in which GSIS was impaired without affecting insulin producing function. The transplantation of 5 × 106 cells resulted in a marked improvement of glucose tolerance within 20 days. This effect decreased but was still observed at 120 days post-transplantation. This demonstrates the feasibility of the novel optimized protocol. 相似文献
74.
This protocol details a method for monitoring glucose uptake into single, living mammalian cells using a fluorescent D-glucose derivative, 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose (2-NBDG), as a tracer. The specifically designed chamber and superfusion system for evaluating 2-NBDG uptake into cells in real time can be combined with other fluorescent methods such as Ca2+ imaging and the subsequent immunofluorescent classification of cells exhibiting divergent 2-NBDG uptake. The whole protocol, including immunocytochemistry, can be completed within 2 d (except for cell culture). The procedure for 2-NBDG synthesis is also presented. 相似文献
75.
Journal of Ichthyology - The Serranidae are well known for protogynous sex change. The red-belted anthias Pseudanthias rubrizonatus inhabits Kagoshima Bay. We aimed to estimate the body size and... 相似文献
76.
Essential role of voltage-dependent anion channel in various forms of apoptosis in mammalian cells 总被引:21,自引:0,他引:21 下载免费PDF全文
Shimizu S Matsuoka Y Shinohara Y Yoneda Y Tsujimoto Y 《The Journal of cell biology》2001,152(2):237-250
Through direct interaction with the voltage-dependent anion channel (VDAC), proapoptotic members of the Bcl-2 family such as Bax and Bak induce apoptogenic cytochrome c release in isolated mitochondria, whereas BH3-only proteins such as Bid and Bik do not directly target the VDAC to induce cytochrome c release. To investigate the biological significance of the VDAC for apoptosis in mammalian cells, we produced two kinds of anti-VDAC antibodies that inhibited VDAC activity. In isolated mitochondria, these antibodies prevented Bax-induced cytochrome c release and loss of the mitochondrial membrane potential (Deltapsi), but not Bid-induced cytochrome c release. When microinjected into cells, these anti-VDAC antibodies, but not control antibodies, also prevented Bax-induced cytochrome c release and apoptosis, whereas the antibodies did not prevent Bid-induced apoptosis, indicating that the VDAC is essential for Bax-induced, but not Bid-induced, apoptogenic mitochondrial changes and apoptotic cell death. In addition, microinjection of these anti-VDAC antibodies significantly inhibited etoposide-, paclitaxel-, and staurosporine-induced apoptosis. Furthermore, we used these antibodies to show that Bax- and Bak-induced lysis of red blood cells was also mediated by the VDAC on plasma membrane. Taken together, our data provide evidence that the VDAC plays an essential role in apoptogenic cytochrome c release and apoptosis in mammalian cells. 相似文献
77.
We performed the in vitro micronucleus (MN) test on 2-[2-(acetylamino)-4-[bis(2-methoxyethyl)amino]-5-methoxyphenyl]-5-amino-7-bromo-4-chloro-2H-benzotriazole (PBTA-1) and 2-[2-(acetylamino)-4-[N-(2-cyanoethyl)-ethylamino]-5-methoxyphenyl]-5-amino-7-bromo-4-chloro-2H-benzotriazole (PBTA-2), which are newly identified water pollutants from the Nishitakase river in Kyoto, Japan, and on their possible mother compounds (AZO DYE) and intermediates (non-ClPBTAs). We tested these compounds in the absence and presence of S9 mix in two Chinese hamster cell lines CHL and V79-MZ and scored MN, polynuclear and karyorrhectic (PN), and mitotic (M) cells. PBTA-2 in the absence of S9 mix induced the strongest responses in both cell lines. It was also a strong inducer of binucleate cells in PN cells in both cell lines, which suggested that it induced polyploidy. PBTA-1 showed clear positive results only in the absence of S9 mix and only in V79-MZ cells, inducing aneuploidy. In CHL cells AZO DYE-1 significantly induced MN cells in the presence of S9 mix, and AZO DYE-2 induced MN and PN cells, including binucleate cells and cells with a multilobed nucleus, in the absence of S9 mix. In V79-MZ cells, AZO DYE-1 and -2 induced primarily M cells in the presence of S9 mix. 9% of the M cells treated with 50 microg/ml AZO DYE-1 showed endoreduplication. AZO DYE-2 at 200 microg/ml condensed the chromatin in 100% of the cells. The non-ClPBTAs were a bit more cytotoxic than the other compounds and induced a slight increase in MN cells in both cell lines. Some of the chemicals tested induced a characteristic karyomorphology that might reflect abnormal cell division. Abnormalities of cell division could be detected in PN and M cells as well as in MN cells. Structure-activity relationships have also been discussed. 相似文献
78.
79.
Yoshida M Sakuma-Mochizuki J Abe K Arai T Mori M Goya S Matsuoka H Hayashi S Kaneda Y Kishimoto T 《Biochemical and biophysical research communications》1999,265(2):503-508
A number of investigators have reported augmented expression of PDGF in lungs with idiopathic pulmonary fibrosis (IPF) or with other types of pulmonary fibrosis. To accomplish such a regulation of PDGF activity, we constructed an expression plasmid of the extracellular domain of PDGF receptor beta chain (XR), which lacks intracellular tyrosine kinase domain and transmembrane portions, and estimated the therapeutic effects of XR gene transfer through the trachea on bleomycin-induced lung fibrosis of C57BL/6 mice using the hemagglutinating virus of Japan(HVJ)-liposome method. The XR gene transfer ameliorated the increases in the wet weight and hydroxyproline content and the histopathologic changes of the lung induced by bleomycin. These findings suggest that PDGF plays a crucial role in the pathogenesis of pulmonary fibrosis, and that XR gene transfer using the HVJ-liposome method may limit the progression of pulmonary fibrosis. 相似文献
80.