In antiviral therapy of hepatitis B virus(HBV)infection,drug resistance remains a huge obstacle to the long-term effectiveness of nucleoside/tide analogs(NAs).Primary resistance mutation(rtM204V)contributes to lamivud...In antiviral therapy of hepatitis B virus(HBV)infection,drug resistance remains a huge obstacle to the long-term effectiveness of nucleoside/tide analogs(NAs).Primary resistance mutation(rtM204V)contributes to lamivudine(LAM)-resistance,and compensatory mutations(rtL180M and rtV173L)restore viral fitness and increase replication efficiency.The evaluation of new anti-viral agents against drug-resistant HBV is limited by the lack of available small-animal models.We established LAM-resistance HBV replication mice models based on clinical LAM-resistant HBV mutants.Double(rtM204VþrtL180M)or triple(rtM204VþrtL180MþrtV173L)lamivudine-resistant mutations were introduced into HBV expression vector,followed by hydrodynamic injection into tail vein of NOD/SCID mice.Viremia was detected on days 5,9,13 and 17 and liver HBV DNA was detected on day 17 after injection.The serum and liver HBV DNA levels in LAM-resistant model carrying triple mutations are the highest among the models.Two NAs,LAM and entecavir(ETV),were used to test the availability of the models.LAM and ETV inhibited viral replication on wild-type model.LAM was no longer effective on LAM-resistant models,but ETV retains a strong activity.Therefore,these models can be used to evaluate anti-viral agents against lamivudine-resistance,affording new opportunities to establish other drug-resistant HBV small-animal models.展开更多
Omega-3 polyunsaturated fatty acids （w-3 PUFAs） are essential components required for normal cellular function and have been shown to have important therapeutic and nutritional benefits in humans. But humans or mamm...Omega-3 polyunsaturated fatty acids （w-3 PUFAs） are essential components required for normal cellular function and have been shown to have important therapeutic and nutritional benefits in humans. But humans or mammals cannot naturally produce w-3 PUFAs, due to the lack of the co-3 fatty acid desaturase gene （fat-1 gene）. Previously, fat-1 gene has been cloned from Caenorhabditis elegans and transferred into mice, pigs and sheep, but not yet into beef cattle. We attempt to transfer it into beef cattle. The object of this paper is to edit the fat-1 gene from C. elegans to express more efficiently in beef cattle and verify its biological function in mice model. As a result, the fat-1 gene from C. elegans was modified by synonymous codon usage and named it Bfat-l. We have demonstrated that degree of codon bias of Brat-1 gene was in- creased in beef cattle. Moreover, Bfat-1 gene could be transiently expressed in mouse liver and muscle, the w-6/co-3 PUFAs ratio of 18 and 20 carbon was decreased significantly in liver （P〈0.05）, and the ratio of 20 carbon decreased significantly in muscle 24 and 72 h after injection （P〈0.05）. This confirms that the Bfat-1 gene modification was successful, and the protein encoded was able to catalyze the conversion of w-6 PUFAs to e0-3 PUFAs.展开更多
Experiments were conducted on a lab-scale fluidized bed to study the distribution of liquid ethanol injected into fluidized catalyst particles. Electrical capacitance measurements were used to study the liquid distrib...Experiments were conducted on a lab-scale fluidized bed to study the distribution of liquid ethanol injected into fluidized catalyst particles. Electrical capacitance measurements were used to study the liquid distribution inside the bed, and a new method was developed to determine the liquid content inside fluidized beds of fluid catalytic cracking particles. The results shed light on the complex liquid injection region and reveal the strong effect of superficial gas velocity on liquid distribution inside the fluidized bed, which is also affected by the imbibition of liquid inside particle pores. Particle internal porosity was found to play a major role when the changing mass of liquid in the bed was monitored. The results also showed that the duration of liquid injection affected liquid-solid contact inside the bed and that liouid-solid mixin~ was not homogeneous durin~ the limited liouid injection time.展开更多
T cell immunoglobulin- and mucin-domain-containing molecule-3 （Tim-3） has been reported to participate in the pathogenesis of inflammatory diseases. However, whether Tim-3 is involved in hepatitis B virus （HBV） in...T cell immunoglobulin- and mucin-domain-containing molecule-3 （Tim-3） has been reported to participate in the pathogenesis of inflammatory diseases. However, whether Tim-3 is involved in hepatitis B virus （HBV） infection remains unknown. Here, we studied the expression and function of Tim-3 in a hydrodynamics-based mouse model of HBV infection. A significant increase of Tim-3 expression on hepatic T lymphocytes, especially on CD8^＋ T cells, was demonstrated in HBV model mice from day 7 to day 18. After Tim-3 knockdown by specific shRNAs, significantly increased IFN-γ production from hepatic CD8^＋ T cells in HBV model mice was observed. Very interestingly, we found Tim-3 expression on CD8^＋ T cells was higher in HBV model mice with higher serum anti-HBs production. Moreover, Tim-3 knockdown influenced anti-HBs production in vivo. Collectively, our data suggested that Tim-3 might act as a potent regulator of antiviral T-cell responses in HBV infection. Cellular ＆ Molecular Immunology.展开更多
The lymphatic system is important in mounting an immune response to foreign antigens and tumors in humans and animal models. The liver produces a large amount of lymph, and its lymphatic system is divided into three m...The lymphatic system is important in mounting an immune response to foreign antigens and tumors in humans and animal models. The liver produces a large amount of lymph, and its lymphatic system is divided into three major components： the portal, sublobular and superficial lymphatic vessels. Despite the fact that mice are the most commonly used laboratory animals, detailed descriptions of the anatomical location and function of the lymph nodes （LNs） that drain the liver are surprisingly absent. In this study, we found that the portal and celiac LNs adjacent to mouse liver were stained with Evans blue within 5-8 min. Enhanced green fluorescence protein （EGFP）-positive cells from the liver also drained into the two aforementioned LNs. These data indicate that the portal and celiac LNs drain the mouse liver. Lymphadenectomy of the identified liver-draining LNs resulted in hepatitis B virus （HBV） persistence in immunocompetent mice compared with the sham group. In addition, the frequencies of CD8＋ T cells and dendritic cells （DCs） increased significantly in the liver-draining LNs after hydrodynamic injection of HBV plasmid. Liver-draining LN cells in HBV plasmid-injected mice also showed significant antigen-specific proliferation in response to stimulation with recombinant hepatitis B core antigen in vitro. Adoptive transfer of these cells into Rag1-/- mice induced a reduction in the serum concentration of hepatitis B surface antigen （HBsAg） compared to liver-draining LN cells in uninjected mice. Altogether our data characterize the liver-draining LNs and provide evidence that the liver-draining LNs induce an anti-HBV-specific immune response responsible for HBV clearance.展开更多
基金This work was supported by the Basic Scientific Research Program of Materia Medica,CAMS(2013ZD05)State Mega Programs(2012ZX09301002-003/006)+1 种基金the Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study(BZ0150)973 Project(2012CB911103).
文摘In antiviral therapy of hepatitis B virus(HBV)infection,drug resistance remains a huge obstacle to the long-term effectiveness of nucleoside/tide analogs(NAs).Primary resistance mutation(rtM204V)contributes to lamivudine(LAM)-resistance,and compensatory mutations(rtL180M and rtV173L)restore viral fitness and increase replication efficiency.The evaluation of new anti-viral agents against drug-resistant HBV is limited by the lack of available small-animal models.We established LAM-resistance HBV replication mice models based on clinical LAM-resistant HBV mutants.Double(rtM204VþrtL180M)or triple(rtM204VþrtL180MþrtV173L)lamivudine-resistant mutations were introduced into HBV expression vector,followed by hydrodynamic injection into tail vein of NOD/SCID mice.Viremia was detected on days 5,9,13 and 17 and liver HBV DNA was detected on day 17 after injection.The serum and liver HBV DNA levels in LAM-resistant model carrying triple mutations are the highest among the models.Two NAs,LAM and entecavir(ETV),were used to test the availability of the models.LAM and ETV inhibited viral replication on wild-type model.LAM was no longer effective on LAM-resistant models,but ETV retains a strong activity.Therefore,these models can be used to evaluate anti-viral agents against lamivudine-resistance,affording new opportunities to establish other drug-resistant HBV small-animal models.
基金funded by the National Key Project for Production of Transgenic Breeding Plan, China (2013ZX08007002, 2014ZX08007-002)the Earmarked Fund for ModernAgro-Industry Technology Research System, China (CARS38)+1 种基金the Agricultural Science and Technology Innovation Program (ASTIP-IAS03)the Fundamental Research Budget Increment Project (2013ZL031) of Chinese Academy of Agricultural Sciences
文摘Omega-3 polyunsaturated fatty acids （w-3 PUFAs） are essential components required for normal cellular function and have been shown to have important therapeutic and nutritional benefits in humans. But humans or mammals cannot naturally produce w-3 PUFAs, due to the lack of the co-3 fatty acid desaturase gene （fat-1 gene）. Previously, fat-1 gene has been cloned from Caenorhabditis elegans and transferred into mice, pigs and sheep, but not yet into beef cattle. We attempt to transfer it into beef cattle. The object of this paper is to edit the fat-1 gene from C. elegans to express more efficiently in beef cattle and verify its biological function in mice model. As a result, the fat-1 gene from C. elegans was modified by synonymous codon usage and named it Bfat-l. We have demonstrated that degree of codon bias of Brat-1 gene was in- creased in beef cattle. Moreover, Bfat-1 gene could be transiently expressed in mouse liver and muscle, the w-6/co-3 PUFAs ratio of 18 and 20 carbon was decreased significantly in liver （P〈0.05）, and the ratio of 20 carbon decreased significantly in muscle 24 and 72 h after injection （P〈0.05）. This confirms that the Bfat-1 gene modification was successful, and the protein encoded was able to catalyze the conversion of w-6 PUFAs to e0-3 PUFAs.
文摘Experiments were conducted on a lab-scale fluidized bed to study the distribution of liquid ethanol injected into fluidized catalyst particles. Electrical capacitance measurements were used to study the liquid distribution inside the bed, and a new method was developed to determine the liquid content inside fluidized beds of fluid catalytic cracking particles. The results shed light on the complex liquid injection region and reveal the strong effect of superficial gas velocity on liquid distribution inside the fluidized bed, which is also affected by the imbibition of liquid inside particle pores. Particle internal porosity was found to play a major role when the changing mass of liquid in the bed was monitored. The results also showed that the duration of liquid injection affected liquid-solid contact inside the bed and that liouid-solid mixin~ was not homogeneous durin~ the limited liouid injection time.
基金supported in part by grants from the National Nature Science Foundation of China (No. 30670966)the National Basic Research Program (No. 2009CB521900)+1 种基金the Taishan Scholar Programthe Scientific Foundation of Innovative Research Team in Shandong University.
文摘T cell immunoglobulin- and mucin-domain-containing molecule-3 （Tim-3） has been reported to participate in the pathogenesis of inflammatory diseases. However, whether Tim-3 is involved in hepatitis B virus （HBV） infection remains unknown. Here, we studied the expression and function of Tim-3 in a hydrodynamics-based mouse model of HBV infection. A significant increase of Tim-3 expression on hepatic T lymphocytes, especially on CD8^＋ T cells, was demonstrated in HBV model mice from day 7 to day 18. After Tim-3 knockdown by specific shRNAs, significantly increased IFN-γ production from hepatic CD8^＋ T cells in HBV model mice was observed. Very interestingly, we found Tim-3 expression on CD8^＋ T cells was higher in HBV model mice with higher serum anti-HBs production. Moreover, Tim-3 knockdown influenced anti-HBs production in vivo. Collectively, our data suggested that Tim-3 might act as a potent regulator of antiviral T-cell responses in HBV infection. Cellular ＆ Molecular Immunology.
基金This work was supported by the Ministry of Science and Technology of China （973 Basic Science Project 2013CB944902）, the Natural Science Foundation of China （Nos. 91029303, 31021061） and the National Science and Technology Major Projects （2013ZX10002002-002）. We thank Professor Pei-Jer Chen for providing the pAAV-HBV plasmid.
文摘The lymphatic system is important in mounting an immune response to foreign antigens and tumors in humans and animal models. The liver produces a large amount of lymph, and its lymphatic system is divided into three major components： the portal, sublobular and superficial lymphatic vessels. Despite the fact that mice are the most commonly used laboratory animals, detailed descriptions of the anatomical location and function of the lymph nodes （LNs） that drain the liver are surprisingly absent. In this study, we found that the portal and celiac LNs adjacent to mouse liver were stained with Evans blue within 5-8 min. Enhanced green fluorescence protein （EGFP）-positive cells from the liver also drained into the two aforementioned LNs. These data indicate that the portal and celiac LNs drain the mouse liver. Lymphadenectomy of the identified liver-draining LNs resulted in hepatitis B virus （HBV） persistence in immunocompetent mice compared with the sham group. In addition, the frequencies of CD8＋ T cells and dendritic cells （DCs） increased significantly in the liver-draining LNs after hydrodynamic injection of HBV plasmid. Liver-draining LN cells in HBV plasmid-injected mice also showed significant antigen-specific proliferation in response to stimulation with recombinant hepatitis B core antigen in vitro. Adoptive transfer of these cells into Rag1-/- mice induced a reduction in the serum concentration of hepatitis B surface antigen （HBsAg） compared to liver-draining LN cells in uninjected mice. Altogether our data characterize the liver-draining LNs and provide evidence that the liver-draining LNs induce an anti-HBV-specific immune response responsible for HBV clearance.
