1.Interleukin-4 antagonists with longer half-life in plasma
Xiyong SONG ; Shaohong CHANG ; Bo LIU ; Xin GONG ; Jun WU
Military Medical Sciences 2014;(11):855-859
Objective To develop an interleukin-4(IL-4) antagonist named M5-IgG1Fc protein constructed by genetic engineering of antibody Fc fragment-cytokine mutein fusion protein which has a long half-life time in plasma.M5-IgG1 Fc protein binds to IL-4 receptor but cannot activate downstream signalling pathway , which provides a basis for drug develop-ment for allergic diseases .Methods The synthesized interleukin-4 mutant gene ( named M5 ) was cloned into the expres-sion vector pBV220 and transformed into E.coli DH5α.Chimeric gene M5-IgG1Fc obtained by overlap extension (SOE) method was transformed into glycoengineered Pichia pastoris GJK01 through expression vector pPICZαA .Then M5-IgGFc fusion protein was obtained by protein purification after being induced by methanol in 72 hours.The anti-IL-4 biologicial ac-tivity assay of M5 and M5-IgG1 Fc was performed with CTLL-2/IL-4R cells and detected with MTT colormetry .Finally,the half-life time of M5 and M5-IgG1 Fc protein in mice was compared by detecting the remaining amount in plasma with ELISA kit.Results The M5 protein expressed in E.coli and M5-IgG1 Fc fusion protein expressed in P.pastoris GJK01 both had IL-4 antagonistic bioactivity .The EC50 of both, which inhibited 5.6 ×10 -2 nmol/ml of IL-4, were 0.31 ±0.05 and 0.77 ± 0.03 nmol/ml,respectively.The maximum of M5 in plasma at 0.5 h was 5.8 ×10 -2 nmol/ml but the remaining amount was 2.8%of the maximum at 2 h.M5 protein could not be detected after administration at 8 h because of the detection line . The maximum of M5-IgG1 Fc fusion protein was 4.7 ×10 -2 nmol/ml,while fusion protein M5-IgG1 Fc decreased to 4.3%of its maximum at 120 h and could not be detected at 168 h.Conclusion M5 protein has IL-4 antagonistic bioactivity .M5-IgG1 Fc fusion protein expressed in glycoengineered P.pastoris GJK01 has IL-4 antagonistic bioactivity and long retention time in mice,which can be potentially used for treatment of allergic diseases .
2.Therapy effect of TA (docetaxel + pirarubicin) or AC(pirarubicin + cyclophosphamide) for neoadjuvant chemotherapy locally advanced breast cancer with triple negative
Haibin CUI ; Xiyong BAI ; Huaie GE ; Wei ZHANG ; Hui LIU
Clinical Medicine of China 2015;(4):345-348
Objective To investigate the clinical efficacy of neoadjuvant chemotherapy regimens of TA or AC in the treatment of locally advanced triple negative breast cancer. Methods Data of 99 women with stageⅡ/ Ⅲ locally advanced triple negative breast cancer treated in the Centre Hospital of Cangzhou from Jan. 2006 to Dec. 2011 were retrospectively analyzed. These patients were divided into two groups based on the regimen of the neoadjuvant chemotherapy. Fifty-two cases were received TA regimen(Docetaxel 75 mg/ m2 and pirarubicin 50 mg/ m2 )and 47 cases were received AC( pirarubicin 50 mg/ m2 ,cyclophosphamide 600 mg/ m2 ). IV drip infusion was administered in both groups for 4 cycles before surgery,with 3 weeks for each cycle. The efficacy after treatment,the 2 year recurrence rate and overall survival rate after operation were compared between the two groups. Results The response rates in TA group were 88. 46% ,higher than that of AC group(57. 45% ),and the difference was statistically significant(χ2 = 12. 260,P < 0. 001). Furthermore,the rate of pathological grade 4 and 5 in TA group were 42. 3%(22 / 52)was superior to AC group(23. 4%(11 / 47);P = 0. 046). The 2-year recurrence rate and survival rate in TA group were 23. 08%(12 / 52)and 84. 62% ,as same as that in AC group ((27. 66%(13 / 47)and 80. 85% ;χ2 = 0. 400;P = 0. 53). Conclusion TA and AC are both effective in terms of females with stage Ⅱ/ Ⅲ locally advanced triple negative breast cancer treat with neoadjuvant chemotherapy. Moreover,TA is superior to AC. However,there is no statistical difference of 2-years recurrence rate and survival rate between two groups.
3.Effects of tianeptine on changes of MAP2 expression level in hippocampal CA3 pyramidal cell of rats in chronic stress
Haiyan JIN ; Shaowen LIU ; Jiuchang ZHONG ; Quan YANG ; Xiyong YU
Chinese Pharmacological Bulletin 2003;0(07):-
Aim To investigate changes of MAP2 expression level in rat hippocampal pyramidal cells induced by chronic stress, and to explore effects of tianeptine on them. Methods 25 rats were divided randomly into three groups:Control group,Stress group and Stree-tianeptine group. The forced-swimming was performed to rats in stress group and stress-tianeptine. Using the immunohistochemistry and the computerized image technique, expression levels of phosphorated MAP2 and the number the Positive cells were assayed quantitatively in each group. Results Compared with control group (149.34?1.81), the phosphorated MAP2 average gray degree in pyramidal cells of stress group (144.99?4.40) was significantly lower, that of the stress-tianeptine group (148.84?2.73) was significantly higher than that of stress group; The number of phosphorated MAP2 positive cells in stress group (40.36?1.35) was significantly less compared withthat of control group (42.73?1.56); that of stress-tianeptine group (42.14?1.62) was significantly more than that of stress group. Conclusion It is suggested that tianeptine could inhibit the enhancement of phosphorated MAP2 expression in hippocampal pyramidal cells induced by chronic stress.
4.Preparation of antibody against ANKRD22 and its expression in colorectal cancer
Yunhua LIN ; Jingwen LIU ; Saisai YANG ; Xiyong LIU ; Hongping WANG
Journal of Preventive Medicine 2019;31(3):231-235
Objective:
To prepare the monoclonal antibody against ankyrin repeat domain 22(ANKRD22)and to investigate its expression in colorectal cancer tissues.
Methods :
The recombinant human ANKRD22 was expressed through E. coli and pET-42a and then used to immunize Balb/c mice after purification. Anti-human ANKRD22 specific monoclonal antibodies were selected by Western blotting with 293T cell lysate highly expressing ANKRD22 as antigen. The expression of ANKRD22 in the tissue microarrays of 112 patients with colorectal cancer was detected by immunohistochemical staining.
Results :
Four specific monoclonal antibodies against human ANKRD22 were screened out of 93 hybridoma cells,which reacted well with natural human ANKRD22. ANKRD22 was mainly distributed in the cytoplasm of colorectal cancer cells. In 112 cases of colorectal cancer,94 cases were detected positive for ANKRD22 expression,with the positive rate of 83.93%. The expression of ANKRD22 was statistically correlated with the expression of p53 and β-catenin(P<0.05),but not with age,sex,location of tumors,AJCC stage,Dukes stage,degree of differentiation,lymph node metastasis and mismatch repair gene expression(P>0.05).
Conclusion
The expression level of ANKRD22 was high in colorectal cancer. ANKRD22 might be involved in the carcinogenesis of colorectal epithelium and be a potential diagnostic marker.
5.Change of TNF? level after the transfection of ?CREB eukaryotic expressive vector in neonatal rat cardiomyocytes
Qian LI ; Xiyong YU ; Gang ZHOU ; Min YANG ; Zhimin LIU ; Chunyu DENG ; Shuguang LIN
Chinese Journal of Pathophysiology 2000;0(10):-
AIM: To construct an eukaryotic expressive vector of cAMP response element binding protein (?CREB ) and observe the regulation effects of ?CREB transfection on TNF? transcription in cardiomyocytes. METHODS: ?CREB gene was obtained after PCR amplification from human heart cDNA library with CREB specific primers. After digestion and ligation, the complete cDNA was inserted into pAdTrack, a shuttle plasmid. Neonatal rat ventricular myocytes were dissociated and cultured. The myocytes were transfected with the vector by liposome-lipofectamine. The expression of transfected ?CREB was confirmed and evaluated with green fluorescent protein (GFP), competitive RT-PCR, and immunocytochemistry. Concentrations of TNF? in cultured supernatants of cardiomyocytes were measured with radioimmunoassay from control, forskolin (10 ?mol/L), transfected, and transfected with adding forskolin (10 ?mol/L) groups. RESULTS: The expression levels of ?CREB in transfected group (mRNA ratio to ?-actin, 1.00?0.05; positive protein 28.88%?9.05%) was significantly higher than that in control group (mRNA 0.76?0.04, P
6.Effect of ketamine on transient outward potassium current of isolated human atrial myocytes
Sujuan KUANG ; Chunyu DENG ; Xiaohong LI ; Xiaoying LIU ; Qiuxiong LIN ; Zhixin SHAN ; Min YANG ; Xiyong YU
Acta Pharmaceutica Sinica 2010;45(7):849-52
The effects of ketamine on transient outward potassium current (I(to)) of isolated human atrial myocytes were investigated to understand the mechanism of part of its effects by whole-cell patch-clamp. Atrial myocytes were enzymatically isolated from specimens of human atrial appendage obtained from patients under going cardiac valve displacing. Ito is recorded in voltage-clamp modes using the patch-clamp technique at room temperature. Currents signals were recorded by an Axopatch 200B amplifier with the Digidata 1322A-pClamp 9.0 data acquisition system. Ketamine decreased I(to) of human atrial myocytes in a dose-dependent manner. The current-voltage curve was significantly lowered, 30, 100, 300, and 1000 micromol x L(-1) ketamine decreased respectively I(to) current density about (13.62 +/- 0.04)%, (38.92 +/- 0.05)%, (72.24 +/- 0.10)% and (83.84 +/- 0.05)% at the potential of 50 mV, with an IC50 of 121 micromol x L(-1). The I(to) activation curve, inactivation curve and the recovery curve were not altered by ketamine. So, ketamine concentration-dependently decreased I(to) of human atrial myocytes.
7.Distribution of genes encoding LPD of nontypeable Haemophilus influenzae A isolates and the immu-noprotective effects of the expressed recombinant LPD
Rongshan WANG ; Hongxing JIN ; Xiyong LIU ; Zhibiao JIN ; Honghui DING ; Jie YAN ; Aihua SUN
Chinese Journal of Microbiology and Immunology 2014;(12):928-932
Objective To investigate the distribution and sequence conservation of genes encoding the outer membrane lipoprotein D(LPD)of nontypeable Haemophilus influenzae(NTHi)isolates and to ana-lyze the immunogenicity and the immunoprotective effects of the expressed recombinant LPD(rLPD). Meth-ods PCR analysis was used to detect the genes encoding LPD of NTHi isolates. The PCR products were se-quenced after T-A cloning. A prokaryotic expression system for genes encoding LPD was established to ex-press the rLPD. Ni-NTA affinity chromatography was used for purification. SDS-PAGE and Bio-Rad Gel Im-age Analyzer were used to detect the expression and the yield of rLPD. The antigenicity and immunoreactivity of rLPD were detected by ELISA and Western blot assay. The immunoprotective effects of rLPD against lethal dose of NTHi were evaluated in a mouse model. Results All of the tested NTHi isolates were positive for the genes encoding LPD. They shared 98. 0% -99. 4% homologies in nucleotide sequences and 98. 5% -100% homologies in amino acid sequences. The established prokaryotic expression system expressed rLPD with a high yield. High levels of antibody in rabbits were induced by the rLPD. The anti-NTHi antiserum samples from rabbits and children could recognize and react with the rLPD. The result of ELISA indicated that 93. 6%(58 / 62)and 53. 2%(32 / 62)of the serum samples from children with NTHi infection were positive for rLPD-IgM and rLPD-IgG,respectively. The rLPD at concentrations of 100 μg and 200 μg could respectively protect 60. 0% and 73. 3% of mice from lethal NTHi infection. Conclusion The genes enco-ding LPD were extensively distributed in NTHi isolates with high sequence conservation. The expressed rLPD could be used as a potential candidate antigen in the development of genetic engineering vaccine against NTHi infection considering its high immunogenicity and immunoprotective effects.
8.Expression of endo-beta-N-acetylglucosaminidase H in Pichia pastoris and its applica-tion to N-glycosylation analysis
Yanyan ZHI ; Shaohong CHANG ; Xin GONG ; Xiyong SONG ; Jun WU ; Bo LIU
Military Medical Sciences 2014;(3):193-197
Objective To prepare endo-beta-N-acetylglucosaminidase H (Endo-H) expressed in Pichia pastoris, and apply it to N-glycosylation analysis .Methods One complete gene was synthesized on the basis of the cDNA sequence encoding Streptomyces plicatus reported in GenBank .The gene was cloned into the expression vector pPIC 9.The expression vector pPIC9-Endo-H was transformed into P.pastoris(JC308).The expression products were induced by methanol , puri-fied by two-step chromatography , used to analyze the glycan structures of RNaseB by the DNA sequencer assisted fluoro-phore-assisted carbohydrate electrophoresis (DSA-FACE)methods, and finally compared with peptide-N-asparagine amidase F(PNGase F).Results This enzyme expressed in P.pastoris(JC308) had the ability to hydrolyze natural or denatured high-mannose type of oligosaccharide linked by β-1,4-glycosidic bonds , but not complex-type oligosaccharide .The result of DSA-FACE showed that carbohydrate chains of Man 5 GlcNAc-Man9 GlcNAc could be obtained when RNaseB was hydrolyzed by Endo-H, and that Man5 GlcNAc2-Man9 GlcNAc2 chains became available when RNaseB was hydrolyzed by PNGase F . Conclusion Endo-H expressed in P.pastoris has bioactivity which can be used to analyze N-glycosylation with the method of DSA-FACE.
9.Construction of a glycoengineering yeast overexpressing N-glycosyltransferase
Yinping MAO ; Xin GONG ; Shaohong CHANG ; Xiyong SONG ; Jun WU ; Bo LIU
Military Medical Sciences 2015;(8):602-606,617
Objective To obtain a strain of glycoengineering yeast with higher N-glycosylation efficiency by overexpressing N-glycosyltransferase.Methods Through the selecting marker URA3 gene, a new glycoengineering yeast strain named 4-32-STT3D was constructed, which could overexpress the Leishmania major N-glycosyltransferase staurosporine and temperature sensitivity3 D subunit(STT3D) under the control of an inducible alcohol oxidase 1(AOX1) promoter.We analyzed the N-glycosylation status of anti-human epidermal growth factor receptor 2 ( HER2 ) antibody and granulocyte macrophage colony stimulating factor (GM-CSF) expressed in 4-32-STT3D using SDS-PAGE,Western blotting and peptide-N-asparigineamidase F(PNGase F).Finally the effect of STT3D on the growth rate of glycoengineering yeast was detected.Results SDS-PAGE showed that anti-HER2 antibody expressed in 4-32-HL had two components:the first one with a relative molecular mass 55 ×103 was glycosylated,while the second one with 50 ×103 was non-glycosylated,but anti-HER2 antibody expressed in 4-32-HL-STT3D had the component of 55 ×103 only without any non-glycosylated 50 ×103 .The above components became 50 ×103 with the digestion of PNGaseF.All of them proved to be antibodies by Western blotting.As a report protein,GM-CSF expressed in 4-32-GM-CSF had two components: 22 ×103 and 20 ×103, while in 4-32-GM-CSF-STT3D there was only one with 22 ×103 .All these components became 18 ×103 with the digestion of PNGase F.Statistical analysis showed that without induction,STT3D had no effect on the growth rate of glycoengineering yeast, while great effect was observed when STT3D was induced.Conclusion Glycoengineering yeast with the overexpression of N-glycosyltransferase has higher N-glycosylation efficiency.
10.A study of inductive factors of embryonic stem cells differentiating into cardiac myocytes in vitro
Lanying LIU ; Kun YANG ; Zhengyu ZHU ; Yuchuan LIU ; Xiyong YU ; Jian TANG ; Wei YIN ; Jianquan MA ; Jun GU
Chinese Journal of Pathophysiology 1989;0(05):-
AIM: To study cellular and molecular mechanisms of cardiac development associated genes ex- pression and its function during early stage cardiomyogenesis. METHODS: (1 ) Mouse embryonic stem cells (ESC) line D3 culture. (2) Inductive culals of ESC differentiated into cardiac myocytes in vitro.(3) Identification of ESC -derived cardiac myocytes: RNA isolation; synthesis of specific primer and RT - PCR; Label of RT - PCR products with [? - 32P] dATP as probes, purifyed by sephadex G - 50 columns, determined the yield of DNA. RNA dot hy- bridization. RESULTS: 80% of ESC differentiated into cardiomyocytes by improved conditional medium. Cardiomy- ocytes contraCted in a synchronous manner. The results of RT - PCR and RNA blot showed that cardiac genes were expressed abundantly and specifically during the early cardiomyogenesis. CONCLUSIONS: ESC were able to be dif- ferentiate into cardiomyocytes. Different concentrations and components of RA, DMSO and FCS affected ESC car- diomyogenesis in de. The optimal result obtained was from the conditional medium, a mixturce of 2 nmol/L retinoic acid (RA), 0.6% dimethyl sulfoxide (DMSO) and 20% fend calf serum (FCS).