1.Prokaryotic expression and antigen characteristics of EB virus latent membrane protein 2 ( EBV-LMP2) multi-epitopes
Lijun LU ; Lingling LI ; Jianxiao LIU ; Jia WANG ; Shanli ZHU ; Xiaofei CHEN ; Lifang ZHANG
Chinese Journal of Microbiology and Immunology 2010;30(7):615-620
Objective To express in prokaryotic system and to analyze the antigenic specificity of EB virus(EBV) latent membrane protein 2(LMP2) multi-epitopes gene rich of T cell and B cell epitopes.Methods Using on-line prediction service, T cell epitopes and B cell epitopes of EB virus latent membrane protein 2 were predicted. The genes rich of CTL and th cell epitopes were selected as the candidate gene sequences, while B cell epitopes around them were taken into account. The finial selected multi-epitope gene was synthesized after being optimized according to prokaryotic codon bias and inserted into prokaryotic expression vector pET32a( + ) to get the recombinant plasmid: pET32a( + )/EBV-LMP2 multi-epitopes. After transformed into E. coli BL21 (DE3) and induced by IPTG, the target multi-epitopes gene can be expressed as Trx-His fusion protein. The expression products can be identified by SDS-PAGE and Western blot. Moreover, rabbit serum antibody to EBV membrane protein and nasopharyngeal carcinoma(NPC) patient serum were used respectively to detect the antigenic specificity of the multi-epitopes. Meanwhile, 6-8 weeks female BALB/c mice were immunized with EBV-LMP2 multi-epitope at 2 week intervals, three times in all, Trx-His protein and PBS were set as the control groups. At the second week after the last immunization, the mice were sacrificed. LDH and indirect ELISA were taken to detect the specific spleen CTL activityand specific IgG in serum, which reflected the immunogenicity of the EBV-LMP2 multi-epitope. Results Two amino acid sequences which locate at the LMP2 (aa195 -232 ) and LMP2 (aa419-436 ) were selected and connected in series to be the target gene. The recombinant plasmid containing EBV-LMP2 multi-epitope gene successfully constructed and the target protein was expressed in E. coli BL21 ( DE3 ). The relative molecular mass(Mr) of The expression products is about 27 × 103 , which matches up to the expected Mr. The antigenic specificity of the multi-epitopes protein was identified by Western blot and the multi-epitopes protein also can be detected by rabbit serum antibody to EBV membrane protein and NPC patient serum respectively. In the result of the animal experiment, EBV-LMP2 multi-epitope was able to induce the specific CTL activity in BALB/c mice. With the increasing of the effector: target ( E: T) 1: 5,1: 10, 1: 25, the CTL activity was also increased wih( 12.52% + 2.59% ), (21.80% + 1.08% ), (23.68% + 3.74% ) respectively; EBV-LMP2 multi-epitope was able to induce LMP2-specific antibody response(A490 =0.258 +0.040) as compared with Trx-His protein(A490 =0.095 +0.011) and PBS(A490 =0.068 +0.014,P<0.05=. Conclusion The EBV-LMP2 multi-epitopes gene was designed successfully and expressed precisely in prokaryotic expression system with good antigenicity and immunogenicity.
2.Cross reaction characteristics of recombinant fusion protein of human papillomavirus 16 type L2
Lingling LI ; Jianxiao LIU ; Shanli ZHU ; Xiangyan XUE ; Jun CHEN ; Lifang ZHANG
Chinese Journal of Laboratory Medicine 2010;33(5):435-440
Objective To investigate the cross reaction characteristics of recombinant human papillomavirus 16 type L2 full-length fusion protein in HPV types of 6, 11, 18.Methods The serum samples of 108 condyloma acuminatum patients, 156 cervix cancer patients and 100 healthy control subjects were collected.The gene of full-length HPV16 L2 was amplificated from the tissue DNA of cervical cancer patient and inserted into the prokaryotic expression vector PGEX-4T-1 to construct the recombinant plasmid PGEX-4T-1-HPV16 L2.After sequencing identification, the recombinant plasmid was tranformed into E.coli BL21 (DE3).After induction by IPTG, the fusion protein containing HPV16 L2 was expressed and analyzed by both SDS-PAGE and WB.Furthermore, the specific binding capacity of the fusion protein to the HPV 6,11, 16 and 18 DNA positive patient's sera were analyzed by WB.The fusion protein was purified with NiNTA Agarose Kit and coated with ELISA reaction plates.The specific serum IgG were detected by indirect ELISA.Results The recombinant plasmid PGEX-4T-1-HPV16 L2 was constructed successfully. Highly expressed HPV16 L2 full-length fusion protein was obtained and the expression level was 27.2 %.The relative molecular mass(Mr) of the fusion protein is about 82 × 103, which matches up to the expected Mr.Meanwhile, the sera of HPV 6,11,16,18 DNA positive patients were used as the primary antibody and the Mr of the specific band was detected to be about 82 × 103 by WB.The results of indirect ELISA showed that the average levels of specific IgG in condyloma acuminatum group, cervical cancer group and healthy control subjects were 0.848 ±0.257, 0.822 ±0.247 and 0.173 ±0.143 with the positive rate of 92.6%, 94.2%and 8.0% respectively.There was no significance of the specific IgG levels between condyloma acuminatum group and cervical cancer group ( F = 0, P > 0.05 ), but there was significant difference of specific IgG levels and positivity among the three groups ( F = 305.201 ,x2 = 253.178, P < 0.01 ).Conclusions The HPV16 L2 full-length fusion protein has better antigenicity.However cross reactions with HPV6, 11 and 18 were found.It can be applied in serological screening reagents for HPV infection and associated cancer.
3.Analysis of etiology and biochemical markers of acute liver failure in children
Haiyan FU ; Xiaoming WANG ; Yali WANG ; Jianxiao ZHANG ; Jingping LI ; Xin ZHAO ; Junying LIU ; Runkai YIN ; Rui CHEN ; Limin YANG
Journal of Clinical Pediatrics 2015;(10):841-845
ObjectiveTo explore the etiology and biochemical markers of acute liver failure (ALF) in children.Methods The cause and the biochemical markers of ALF in children who were treated in December 2014 to January 2011 were ana-lyzed retrospectively.ResultsA total of 67 children were enrolled, including 31 females and 36 males. According to the cause of the disease, the children were divided into non-genetic metabolic group, genetic metabolic group, and cryptogenic group. In the non-genetic metabolic group (29 cases, 43.28%) there were 12 cases of drug-induced ALF, 5 cases of Reye syndrome, 3 cases of hemophagocytic syndrome, 3 cases of herpes simplex virus infection, 2 cases of autoimmune hepatitis, one of case mushroom poisoning one case of hepatitis A virus infection, one case of cytomegalovirus infection and one case of sepsis respectively. In the genetic metabolic group (14 cases, 20.90%) there were 6 cases of Wilson’s disease, 2 case of glycogen storage disease, 2 of cas-es progressive familial intrahepatic cholestasis, 2 cases of neonatal intrahepatic cholestasis caused by citrin deifciency, one case of very long-chain acyl coenzyme A dehydrogenase deifciency and one case of primary carnitine deifciency. In the cryptogenic group there were 24 cases (35.82%). The serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin, blood glucose level and AST/ALT were statistically signiifcantly different in genetic metabolic group from in non-genetic me-tabolism disease group and cryptogenic group, (P<0.05). The genetic metabolic group had the lowest levels of serum ALT, AST, albumin and glucose while the genetic metabolic group had the highest ratio of AST/ALT.ConclusionsThe etiology of ALF in children are complex. Genetic metabolic disease should be considered when the child with ALF has no signiifcantly elevated ALT, extremely high ratio of AST/ALT, combined with hypoproteinemia and hypoglycemia.
4.Progression in the application of machine learning in acute respiratory distress syndrome.
Weijun ZHANG ; Jianxiao CHEN ; Yuan GAO
Chinese Critical Care Medicine 2023;35(6):662-664
Acute respiratory distress syndrome (ARDS) is a clinical syndrome defined by acute onset of hypoxemia and bilateral pulmonary opacities not fully explained by cardiac failure or volume overload. At present, there is no specific drug treatment for ARDS, and the mortality rate is high. The reason may be that ARDS has rapid onset, rapid progression, complex etiology, and great heterogeneity of clinical manifestations and treatment. Compared with traditional data analysis, machine learning algorithms can automatically analyze and obtain rules from complex data and interpret them to assist clinical decision making. This review aims to provide a brief overview of the machine learning progression in ARDS clinical phenotype, onset prediction, prognosis stratification, and interpretable machine learning in recent years, in order to provide reference for clinical.
Humans
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Hypoxia/complications*
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Respiratory Distress Syndrome/etiology*
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Prognosis
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Machine Learning
5.Development and primary evaluation of a minimally invasive surgical robot system in endoscopic submucosal dissection: an ex vivo feasibility study
Xiaoxiao YANG ; Huxin GAO ; Shichen FU ; Jianxiao CHEN ; Cheng HOU ; Zhifeng ZHOU ; Rui JI ; Huicong LIU ; Hongliang REN ; Lining SUN ; Jialin YANG ; Xiaoyun YANG ; Yanqing LI ; Xiuli ZUO
Chinese Journal of Digestive Endoscopy 2023;40(3):182-188
Objective:To develop a novel, flexible, dual-arm, master-slave digestive endoscopic minimally invasive surgical robot system named dual-arm robotic endoscopic assistant for minimally invasive surgery (DREAMS) and to evaluate its feasibility for endoscopic submucosal dissection (ESD) by using ex vivo porcine stomachs.Methods:A novel endoscopic robot (DREAMS) system was developed which was composed of a flexible two-channel endoscope, two flexible robotic manipulators, a master controller, a robotic arm, and a control system. A total of 10 artificial round-like lesions with diameters ranging from 15 to 25 mm were created (5 in gastric antrum and 5 in gastric body) by using fresh peeled stomach of healthy pigs as the model. Submucosal dissection was performed with the assistance of the DREAMS system by two operators. The main outcome was submucosal dissection speed, and the secondary outcomes included muscular injury rate, perforation rate, and grasping efficiency of the robot.Results:All 10 lesions were successfully dissected en bloc by using the DREAMS system. The diameter of the artificial lesions was 22.34±2.39 mm, dissection time was 15.00±8.90 min, submucosal dissection speed was 141.79±79.12 mm 2/min, and the number of tractions required by each ESD was 4.2 times. Muscular injury occurred in 4/10 cases of ESD. No perforation occurred. Conclusion:The initial animal experiment shows the DREAMS system is safe and effective.