1. Effects of tissue factor pathway inhibitor-2 on the growth and angiogenesis of subcutaneous tumor xenografts in nude mice established from human liver cancer cells
Tumor 2013;33(2):157-163
Objective: To investigate the effects of TFPI-2 (tissue factor pathway inhibitor 2) on the growth and angiogenesis of subcutaneous tumor xenografts in nude mice established from human liver cancer cells. Methods: The Hep3B cells stably expressing TFPI-2 (Hep3B-TFPI-2 group) and the Hep3B cells transfected with empty vector PCDNA3.1 (Hep3B-V group) or without transfection (Hep3B-P group) were subcutaneously transplanted into nude mice respectively to generate subcutaneous tumor xenografts. The volume of tumor xenograft was measured every three days, and the growth curve of tumor xenograft was drawn when the subcutaneous tumor xenograft was visible. The nude mice were killed three weeks after transplant, the volume of tumor xenograft was measured, and the total RNAs and proteins in tumor xenografts were extracted. The mRNA and protein expressions of TFPI-2 and VEGF (vascular endothelial growth factor) in tumor xenografts were analyzed by RFQ-PCR (real-time fluorescence quantitative PCR) and Western blotting, respectively. The expression of TFPI-2 protein and the MVD (microvessel density) in tumor xenografts were observed by immunohistochemistry. Results: The eventual tumor volume of tumor xenografts in Hep3B-TFPI-2 group was apparently smaller than those in Hep3B-V group and Hep3B-P group (both P < 0.05). The expression of mRNA and abundance of protein of TFPI-2 in Hep3B-TFPI-2 group were significantly higher than those in the other two groups (P < 0.05); while the expression of mRNA and abundance of protein of VEGF in Hep3B-TFPI-2 group were apparently lower than those in the other two groups. Compared with Hep3B-V group and Hep3B-P group, the inhibitory rates of VEGF protein expression in Hep3B-TFPI-2 group were 19.8% and 23.5%, respectively (P < 0.05). The MVD in Hep3B-TFPI-2 group was apparently lower than those in the other two groups (P < 0.05). Conclusion: TFPI-2 can significantly inhibit the growth and angiogenesis of subcutaneous tumor xenografts in nude mice established from hepatocarcinoma Hep3B cells. Copyright © 2013 by TUMOR.
2. Expression of mouse PD-1/PD-L1 recombinant protein in prokaryotic cells
Academic Journal of Second Military Medical University 2010;31(4):385-389
Objective: To establish a molecule binding model of mouse PD-1/PD-L1 protein in vitro, so as to lay a foundation for studying the biological activities of the recombinant protein and to establish a high throughput drug screening model. Methods: Prokaryotic expression plasmid pET28 a (+) /mPDL-1 and pGEX-4T-1/mPD-1 were transformed to E. coli BL21 (DE3), which was then induced with IPTG. The expression products were purified by fast affinity chromatography with FPLC Protein Purification Instrument or gel separation. ELISA and GST pull-down were used to detect the interaction between mPD-1 and mPD-L1. In addition, Alamar blue was used to test the role of protein mixtures in the mixed lymphocyte proliferation. Results: SDS-PAGE and Western blotting analysis showed that the recombinant proteins were successfully expressed. Then purified mPD-1 and mPD-L1 protein was obtained by affinity chromatography, Gel seperation and refolding, etc. ELISA and GST pull-down showed that mPD-1 and mPD-L1 protein had a specific binding activity in vitro. The mPD-1/ mPD-L1 protein had a significantly decreased influence on the proliferation of lymphocytes(P<0. 05). Conclusion: Mouse PD-1/PD-L1 recombinant protein model has been successfully established using purified mPD-1 and mPD-L1 protein expressed prokaryotically, which lays a foundation for high-throughput drug screening.
4.Preparation of recombinant firefly luciferase by a simple and rapid expression and purification method and its application in bacterial detection
Qin XIAO ; Hui CHEN ; Jinming LIN
Journal of Pharmaceutical Analysis 2010;22(2):97-101
A simple and rapid expression and purification method of recombinant firefly luciferase was developed for bacteria detection. A modified luciferase gene from North American firefly Photinus pyralis was cloned into pET28a expression vector and the recombinant protein was produced in Escherichia coli BL21. The recombinant luciferase, equipped with a polyhistidine affinity tag, was purified by immobilized metal ion affinity chromatography (IMAC). The approach generated an abundant expression and an efficient purification of a recombinant luciferase with final yield 1.995mg/L of cell culture. Experiments on the recombinant luciferase also showed that the relative light units (RUL) of the enzyme were 5.8×108, and the specific activity was 2.9×1010 RLU/mg. By applying adenosine triphosphate (ATP) bioluminescence to detection of the coin bacteria using the recombinant protein, the ATP content of bacteria was 9.48×10-16mol/mL, and was identical to the bacteria counts (4500CFU/mL) in order of magnitude. Taken together, our results provided a simple and efficacious method of the preparation of recombinant luciferase, which could be applied in the determination of bacteria via ATP bioluminescence.
5.The role of eNOS on the regulatory effects of EPO on mitochondrial biogenesis in cardiomyocytes exposed to chronic hypoxia
Chuan QIN ; Lin CHEN ; Yinbing XIAO
Chongqing Medicine 2015;(16):2167-2169,2173
Objective To explore the role of endothelial nitric oxide synthase(eNOS) in the regulatory effects of erythropoie‐tin (EPO) on mitochondiral biogenesis in cardiomyocytes exposed to chronic hypoxia .Methods H9c2 cardiomyocytes were cultured in the environment of hypoxia for 1 week(94% N2 ,5% O2 ) ,establishing the chronic hypoxic cardiomyocyte model .All the cells were divided into 3 groups :HC(chronic hypoxic control) ,HE[treated with chronic hypoxia and 20 U/mL recombinant human EPO (rhEPO) ]and HR(cells transfected with eNOS shRNA plasmid and treated with 20 U/mL rhEPO and chronic hypoxia) .Fluores‐cent probe was used to detect the changes of mitochondial number .Mitochondial DNA (mtDNA) relative express level was assayed by RT‐PCR .The expression and phosphorylation of eNOS protein were analyzed with Western blot .Results rhEPO significantly increased the phosphorylation of eNOS and elavated the mitochondialt number and mtDNA (P< 0 .05) .shRNA interference on eNOS significantly blocked all the above changes induced by rhEPO (P<0 .05) .Conclusion Phosphory lation of eNOS is the im‐portant signalling pathway for the enhanced mitochondrial biogenesis in cardiomyocytes exposed to chronic hypoxia by EPO .
7.Direct infection of colony forming unit-megakaryocyte by human cytomegalovirus contributes the pathogenesis of idiopathic thrombocytopenic purpura.
Yan, XIAO ; Wen, LIN ; Qin, LIU ; Runming, JIN ; Hongbao, FEI
Journal of Huazhong University of Science and Technology (Medical Sciences) 2006;26(5):555-7
Human cytomegalovirus (HCMV) late mRNA expression in megakaryoblast and in turn the pathogenesis of idiopathic thrombocytopenic purpura (ITP) patients with HCMV infection, and effectiveness of ganciclovir were investigated. Colony forming unit-megakaryocytes (CFU-MK) of 46 ITP patients with HCMV infection were incubated from patients' bone marrow mononuclear cells (MNC). Reverse transcriptase-polymerase chain reaction (RT-PCR) was subsequently used for CFU-MK for HCMV-late mRNA detection. Ganciclovir therapy was given to both HCMV-late mRNA positive and negative groups for comparison of therapeutic effectiveness. The results in 19 of 46 CFU-MK culture cells specimens with positive HCMV-DNA by PCR or positive CMV-IgM by enzyme linked immunosorbent assay (ELISA) in the correspondent serum of peripheral blood were positive for HCMV-late mRNA. Sixteen out of 19, patients with positive HCMV-late mRNA CFU-MK had a positive response to ganciclovir. Amongst 27 patients with negative HCMV-late mRNA CFU-MK, only 4 positive responders to ganciclovir therapy were observed. Curative effectiveness of ganciclovir in HCMV-late mRNA positive group was significantly higher than that in HCMV-late mRNA negative group (P<0.01). It was suggested that HCMV could directly infect CFU-MK, which might be one of the mechanisms responsible for HCMV related ITP. The ganciclovir is an effective therapy in resulting in the increases in thrombocyte in the ITP patients whose HCMV- late mRNA was positive in their CFU-MK.
9.Effects of chronic hypoxia on left and right ventricular function and the expression of cardiac TRPC channels in rats.
Hui-Qin CHEN ; Mo-Jun LIN ; Xiao-Ru LIU
Chinese Journal of Applied Physiology 2014;30(3):274-278
OBJECTIVETo explore the effects of chronic hypoxia on left and right ventricular function and the expression of cardiac transient receptor potential canonical (TRPC) channels in rats.
METHODSForty eight SD male rats were randomly divided into control group (CON) and chronic hypoxic pulmonary hypertension model group (CH) (n = 24). In CH group, rats were exposed in chronic hypoxia environment (10% +/- 0.2% O2) to induce myocardial hypertrophy. After 3 weeks, mean systemic arterial pressure (mSAP), right ventricular systolic pressure (RVSP), left ventricular systolic pressure (LVSP), left or right ventricular pressure maximum rate of rise (LV/RV + dp/dt(max)), left or right ventricular pressure maximum rate of descent (LV/RV-dp/dt(max)), right ventricular hypertrophy index (RVMI) and left ventricular hypertrophy index (LVMI) were measured. Left and right ventricular myocardium tissue sections were stained by HE and observed under light microscope. Real-time polymerase chain reaction (real-time-PCR) and Western blot were performed to detect the expression of TRPC subfamily.
RESULTSRVSP, RVMI, RV + dp/dt(max) and RV-dp/dt(max) were markedly elevated in CH group (P < 0.01) in comparison to CON group. LVMI was markedly reduced in CH group in comparison to CON group (P < 0.01). LVSP, LV + dp/dt(max) and LV- dp/dt(max) had no significant changes in CH group in comparison to CON group. Right ventricular myocardial cells of CH group became thick, the nuclei stained deeply, the shape of nuclei became not regularity. Left ventricular myocardial fibers did not change significantly. There was significant difference in the levels of mRNA and protein of TRPC1 between CON and CH groups.
CONCLUSIONFor three weeks exposed to chronic hypoxia induced right ventricular hypertrophy specifically, raised the mRNA and protein expression of TRPC1 on right ventricular myocardial cells . TRPC1 might be involved in the development of cardiac hypertrophy.
Animals ; Disease Models, Animal ; Hypertension, Pulmonary ; metabolism ; physiopathology ; Hypoxia ; metabolism ; physiopathology ; Male ; Rats ; Rats, Sprague-Dawley ; Transient Receptor Potential Channels ; metabolism ; Ventricular Function, Left ; physiology ; Ventricular Function, Right ; physiology
10.The comparing research of anticoagulation with sodium citrate or heparin in continuous venovenous hemodiafil- tration.
Xiao-Mao LIN ; Zhi-Mei QIN ; Liang CHEN ; Al ET ;
Chinese Journal of Practical Internal Medicine 2006;0(S1):-
Objective To investigate the anticoagultive effectiveness and specialty of sodium citrate comparing with hep- arin in continuous venovenous hemodiafiltration (CVVHDF).Methods 50 multiple organ disorder patients undergoing CWHDF were randomly divided into two groups:group A(sodium citrate)27 cases,group B(heparin)23 cases,blood e- lectrolyte,acid-alkali degree,cruor index changes,the blood coagulation of tube path way and blood filter were recor- ded.As the same time,side effects were observed in theraphy.Results The patients of two groups were kept stable vital signs,serum electrolyte and blood gas markers during the therapeutic periods.Moreover,ideal serum creatinine and urea clearance rate and uhrafiltration rate were obtained in all patients.The coagulation and longevity of blood filter of Group A are better than Group B,Group A without sigaificantly prolonged cruor index inside body,the dosage of calcium gluco- nate in Group A are greater than Group B.Conclusion Out body anticongulation of sodium citrate is more effective and reliable than regular heparin anticoagulation.