2.Preparation and penetrating effect of the polyarginine-enhanced green fluorescence protein fusion protein.
Nan ZHANG ; Yin BAI ; Jingzhuang ZHAO ; Xianlong YE ; Wenfei WANG ; Guiping REN ; Deshan LI ; Yan JING
Chinese Journal of Biotechnology 2013;29(11):1644-1653
The aim of the study is to establish a platform to deliver therapeutic proteins into target cells through a polyarginine-based cell penetrating peptide. To facilitate the expression of therapeutic proteins, a pSUMO (Small Ubiquitin-like Modifier)-R9-EGFP (enhanced green fluorescence protein) prokaryotic expression vector was constructed. After induction, the fusion protein SUMO-R9-EGFP was efficiently expressed. To validate the cell penetrating ability of the fusion protein, HepG2 cells were incubated with the purified R9-EGFP or EGFP protein as control, internalization of the fluorescent proteins was examined by either flow cytometry or confocal microscopy. The result obtained by flow cytometry showed that the R9-EGFP fusion protein could efficiently penetrate into the HepG2 cells in a dose and time-dependent manner. In contrast, the fluorescence was barely detected in the HepG2 cells incubated with EGFP control. The fluorescence intensity of the R9-EGFP treated cells reached plateau phase after 1.5 h. The result obtained by confocal microscopy shows that R9-EGFP efficiently entered into the HepG2 cells and was exclusively located in the cytoplasm, whereas, no fluorescence was detected in the cells incubated with the EGFP control. The heparin inhibition experiment showed that heparin could inhibit penetrating effect of the R9-EGFP protein by about 50%, suggesting that the penetrating ability of the fusion protein is heparin-dependent. In summary, the study has established a platform to deliver therapeutic proteins into target cells through a polyarginine-based penetrating peptide.
Cell-Penetrating Peptides
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biosynthesis
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genetics
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pharmacology
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Genetic Vectors
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genetics
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Green Fluorescent Proteins
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biosynthesis
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genetics
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Hep G2 Cells
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Humans
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Peptides
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genetics
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metabolism
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Protein Transport
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Recombinant Fusion Proteins
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biosynthesis
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genetics
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pharmacology
3.Establishment of a novel cell model targeted on FGF-21 receptor for screening anti-diabetic drug candidates.
Hongmei GAO ; Wenfei WANG ; Qiao ZHANG ; Yang HAN ; Qi WANG ; Guiping REN ; Yunwei FU ; Deshan LI
Acta Pharmaceutica Sinica 2011;46(8):904-9
The aim of this project is to establish a fibroblast growth factor-21 (FGF-21) signaling pathway targeted cell model, for screening a class of FGF-21 receptor agonists as anti-diabetic candidates. FGF-21 requires beta klotho transmembrane proteins as co-receptor for the activation of tyrosine kinase FGF receptor (FGFR) signaling, thereby activating a series of intracellular signaling pathways and regulating gene transcription for glucose metabolism. Firstly a recombinant plasmid expressing co-receptor beta klotho and EGFP reporter genes was constructed. After introducing the recombinant plasmid into package cells, the cell culture supernatant was used to infect 3T3-L1 cells, which were then screened for stably expressing beta klotho gene. Administration of FGF-21 increased the expression of GLUT1 and stimulated GLUT1-mediated glucose uptake. This novel cell model can be conveniently used in high-throughput drug screening of FGF-21 or FGF-21 analogues.
4.Expression and pharmacological evaluation of fusion protein FGF21-L-Fc.
Wenbing YAO ; Guiping REN ; Yang HAN ; Hongwei CAO ; Hongmei GAO ; Fangming KAN ; Qi WANG ; Deshan LI
Acta Pharmaceutica Sinica 2011;46(7):787-92
FGF21 (fibroblast growth factor 21) is a recently described member of the FGF family. It has been previously demonstrated that FGF21 is a potent regulator of glucose homeostasis. To improve stability of FGF21 for better efficacy, a new form of recombinant FGF21 was generated by fusion of a full length FGF21 gene and the Fc fragment of human IgG4 with flexible linker sequence. To examine the glucose regulation activity of FGF21-L-Fc, 3T3-L1 pre-adipocytes were differentiated into adipocytes, and glucose uptake activity of FGF21-L-Fc was examined by glucose oxidase and peroxidase (GOD-POD) assay. The results showed that in comparison with wild type FGF21, FGF21-L-Fc was more potent in stimulation of glucose uptake by 3T3-L1. In vivo studies on the modified protein demonstrated that FGF-L-Fc had a better efficacy in lowering blood glucose of the STZ-induced diabetic animals and controlled glucose level for a longer time. The results provided a sound basis for further studies.
5.Construction, expression, and bio-activity assay of an anti-IL-1βscfv and TNFR1 fusion protein
Fangming KAN ; Guiping REN ; Mo GUO ; Yang HAN ; Jianying QI ; Yu ZHANG ; Yakun ZHANG ; Deshan LI
Chinese Journal of Microbiology and Immunology 2012;(10):855-860
Objective To express the anti-IL-1βscfv and soluble TNF receptor 1 (sTNFR1),and analyze their bio-activities.Methods sTNFR1 was obtained by RT-PCR from the total RNA of HeLa cells,and fused with IL-1βscfv by the hinge fragment of IgG molecule.The fusion gene IL-1scfv:TNFR1 was cloned into the expression vector pET27b(+).The fusion protein was expressed and purified from inclusion bodies.Results The ELISA analysis showed that the fusion protein could bind hIL-1β and hTNF-α respectively in a dose-dependent manner,indicating that scfv and sTNFR in the fusion protein can form the correct spatial configuration.The dolt-blot analysis showed that the fusion protein could concurrently bind with hIL-1β and hTNF-α,indicating that the combination of the two parts of the fusion protein does not influence each other for binding to their target molecules.The bioactivity assay showed that the fusion protein could inhibit both the cytotoxicity of hTNF-α on L929 cells and hIL-1β-induced proliferation of L929 cells,indicating that the fusion protein has the ability to neutralize hTNF-α and hIL-1β.Conclusion A bispecific fusion protein IL-1scfv:TNFR1 was successfully constructed.The fusion protein has the ability to inhibit the biological activity of hTNF-α and hIL-1β,and provides a drug candidate for the treatment of rheumatoid arthritis.
6.JMJD3 participates in activation and apoptosis of IFN-αand TLR7-induced B cells
Hongye FAN ; Baohui LI ; Fei LIU ; Deshan REN ; Yayi HOU ; Changlin ZHOU
Chinese Journal of Immunology 2015;(7):890-894
Objective:To explore the effect of histone demethylase JMJD3 on B cell activation and apoptosis.Methods:B cells were sorted and purified from the peripheral blood of healthy people and SLE patients by using magnetic bead.After B cells were treated with IFN-αor R848 or IFN-α+R848,the percentages of CD86+B cells,CD69+B cells,CD86+Annexin V+B cells and CD69+Annexin V+B cells were detected by flow cytometry.The expression of JMJD3 was detected by Real Time PCR and Western blot.Results:The purity of sorted B cells was up to 95%.IFN-αenhanced both the activation and apoptosis and the JMJD3 expression of TLR7-activated B cells.The expression of JMJD3 was dependent on MAPK signal pathway,but not the NF-κB signaling pathway.Moreover,JMJD3 was highly expressed in B cells of peripheral blood from SLE patients compared to those from healthy people.Furthermore,JMJD3 inhibitors could inhibit the activation and apoptosis of IFN-αand R848 activated B cells.Conclusion:JMJD3 participated in the activation and apoptosis of IFN-αand TLR7-induced B cells, suggesting JMJD3 inhibitors may possess therapeutic effect for alleviating symptom of SLE.
7.Antitumor activity of the recombinant rClone30-CD/5-FC system.
Zheng LU ; Tianyuan ZHANG ; Miaomiao HAN ; Fuliang BAI ; Wei WU ; Guiyou TIAN ; Guiping REN ; Deshan LI
Acta Pharmaceutica Sinica 2013;48(2):261-8
5-Flucytosine (5-FC) could be changed to 5-fluorouracil (5-FU) by cytosine deaminase (CD), the latter is able to kill cancer cells. However, there is no efficient method to deliver the CD gene into the tumor cells, which hampers the application of the suicide gene system. In this experiment, for the first time, the NDV has been utilized as a vector to deliver the CD gene into the cancer cells, the virus can infect the cancer cells specifically, replicate and assemble, while the cytosine deaminase is expressed. Then the CD converts the prodrug 5-FC into 5-FU to achieve the purpose of inhibiting tumor. Firstly, the whole genome of E. coli JM109 was extracted, and the CD gene was obtained by cloning method. Then the CD and IRES-EGFP were ligated into the pEE12.4 expression vector to become a recombinant pEE12.4IE-CD eukaryotic expression plasmid. The human liver cancer cells were transfected with the plasmid. The cells were treated with different concentrations of 5-FC, MTT method was used to determine the killing effect of CD/5-FC system on the human liver cancer cells. The cell deaths were 18.07%, 42.98% and 62.20% respectively when the concentrations of prodrug were at 10, 20 and 30 mmol x L(-1). In 5-FC acute toxicity experiment, Kunming mice were injected with different concentrations of 5-FC at intervals of 1:0.5. The LD50 of 5-FC through iv injection was determined by improved Karber's method, the LD50 was 507 mg x kg(-1) and the 95% confidence limit was 374-695 mg x kg(-1). According to the maximum LD0 dose of the LD50, the maximum safe dose was 200 mg x kg(-1). Body weight and clinic symptoms of the experimental animals were observed. These results laid the foundation to verify the antitumor effect and safety of CD/5-FC system in animal models. The CD gene was ligated into the NDV (rClone30) carrier, then the tumor-bearing animal was established to perform the tumor inhibiting experiment. The result showed that the recombinant rClone30-CD/5-FC system has a high antitumor activity in vivo. To summarize, CD gene has been cloned and its bioactivity has been confirmed in the mammalian cells. It is the first time in this study to utilize the recombinant NDV to deliver the CD gene into the tumor cells; our result proves the rClone30-CD/5-FC system is a potential method for cancer therapy.
8.The long lasting effect of the murine fibroblast growth factor-21 on blood glucose control of diabetic animals.
Jingzhuang ZHAO ; Guopeng SUN ; Xianlong YE ; Jinnan LI ; Guiping REN ; Wenfei WANG ; Mingyao LIU ; Deshan LI
Acta Pharmaceutica Sinica 2013;48(3):352-8
Insulin is the most common medicine used for diabetic patients, unfortunately, its effective time is short, even the long-acting insulin cannot obtain a satisfactory effect. Fibroblast growth factor (FGF)-21 is a recently discovered glucose mediator and expected to be a potential anti-diabetic drug that does not rely on insulin. In this study, db/db mice were used as the type 2 diabetic model to examine whether mFGF-21 has the long-term blood lowering effect on the animal model. The results showed that mFGF-21 could stably maintain the blood glucose at normal level for a long-term in a dose-dependent manner. Administration of mFGF-21 once a day with three doses (0.125, 0.25 and 0.5 mg x kg(-1)) could maintain blood glucose of the model animals at normal level for at least 24 h. Administration of mFGF-21 every two days with the same doses could maintain blood glucose of the model animals at normal level for at least 48 h, although it took longer time for blood glucose to reach to normal level depending on doses used (twenty injections for 0.125 mg x kg(-1) and 0.25 mg x kg(-1) doses, ten injections for 0.5 mg x kg(-1) dose). Surprisingly, the blood glucose of the treated model animals still maintained at normal level for 24 h after the experiment terminated. Glycosylated hemoglobin level of the animals treated with mFGF-21, which represented long-term glucose status, decreased significantly compared to the control group and the insulin group. The results suggest that FGF-21 has potential to become a long-acting and potent anti-diabetic drug.
9.FGF-21 protects H9c2 cardiomyoblasts against hydrogen peroxide-induced oxidative stress injury.
Miaomiao HAN ; Wenfei WANG ; Mingyao LIU ; Deshan LI ; Bing ZHOU ; Yinhang YU ; Guiping REN
Acta Pharmaceutica Sinica 2014;49(4):470-5
Fibroblast growth factor-21 (FGF-21) is an important metabolism regulator, however, whether FGF-21 has effects on cardiovascular remains unclear. In this study, H2O2-induced injury in H9c2 cells was used as a cell model, the anti-apoptosis potential and mechanism of FGF-21 against oxidative injury were evaluated by MTT assay, flow cytometry assay and real-time PCR. The results showed that FGF-21 could increase the cell survival of H2O2-induced injury in H9c2 cells and prevent H9c2 cells from oxidative stress-induced apoptosis. Furthermore, FGF-21 can elevate SOD activity and regulate Bcl-2/Bax expression in H9c2 cells. The results suggest that FGF-21 have protective effect against the H2O2-induced apoptosis in H9c2 cells.
10.Early apoptosis leads to decrease of B cells in MRL/lpr mice
Baohui LI ; Hongye FAN ; Fei LIU ; Deshan REN ; Yayi HOU ; Changlin ZHOU
Chinese Journal of Immunology 2016;32(3):385-389
Objective:To explore the change of B cell numbers in active MRL/lpr lupus mice , and their regulation mechanisms.Methods:B cell cycle and the percent of B cells in spleen lymphocytes of active MRL /lpr lupus mice and normal C 57/B6 mice were analyzed by using flow cytometry .The apoptotic B cells and their subclass were analyzed by Annexin V and PI staining.Further more ,B cells were purified by magnetic sorting , and real-time quantitative PCR was carried out to detect apoptosis-related gene.Results:Compared with the C57/B6 mice,the percent of B cells in active MRL/lpr lupus mice were significantly reduced (P<0.01),while the percent of apoptotic cells were significantly increased (P<0.01).The percent of early apoptotic B cells were sig-nificantly increased ( P <0.01 ) which including the immature and mature B cells , while the late apoptotic B cells were unchanged.Further more,we found that the anti-apoptotic protein BIRC3 was significantly reduced in active lupus B cells (P<0.01), while the pro-apoptotic protein BCL2L1 and BBC3(PUMA) were significantly increased(P<0.01).Conclusion: B cells in active lupus mice were significantly reduced while early apoptotic B cells were increased , which may be attributed to the changed balance between the anti-apoptotic and pro-apoptotic proteins , suggesting the reduction of B cells in SLE patients may be related to their increased early apoptosis .