The published article titled“Truncated Bid Overexpression Induced by Recombinant Adenovirus Cre/LoxP System Suppresses the Tumorigenic Potential of CD133+Ovarian Cancer Stem Cells”has been retracted from Oncology Re...The published article titled“Truncated Bid Overexpression Induced by Recombinant Adenovirus Cre/LoxP System Suppresses the Tumorigenic Potential of CD133+Ovarian Cancer Stem Cells”has been retracted from Oncology Research,Vol.25,No.4,2017,pp.595–603.展开更多
Recombinant tissue plasminogen activator is commonly used for hematoma evacuation in minimally invasive surgery following intracerebral hemorrhage.However,during minimally invasive surgery,recombinant tissue plasminog...Recombinant tissue plasminogen activator is commonly used for hematoma evacuation in minimally invasive surgery following intracerebral hemorrhage.However,during minimally invasive surgery,recombinant tissue plasminogen activator may come into contact with brain tissue.Therefore,a thorough assessment of its safety is required.In this study,we established a mouse model of intracerebral hemorrhage induced by type VII collagenase.We observed that the administration of recombinant tissue plasminogen activator without hematoma aspiration significantly improved the neurological function of mice with intracerebral hemorrhage,reduced pathological damage,and lowered the levels of apoptosis and autophagy in the tissue surrounding the hematoma.In an in vitro model of intracerebral hemorrhage using primary cortical neurons induced by hemin,the administration of recombinant tissue plasminogen activator suppressed neuronal apoptosis,autophagy,and endoplasmic reticulum stress.Transcriptome sequencing analysis revealed that recombinant tissue plasminogen activator upregulated the phosphoinositide 3-kinase/RAC-alpha serine/threonine-protein kinase/mammalian target of rapamycin pathway in neurons.Moreover,the phosphoinositide 3-kinase inhibitor LY294002 abrogated the neuroprotective effects of recombinant tissue plasminogen activator in inhibiting excessive apoptosis,autophagy,and endoplasmic reticulum stress.Furthermore,to specify the domain of recombinant tissue plasminogen activator responsible for its neuroprotective effects,various inhibitors were used to target distinct domains.It has been revealed that the epidermal growth factor receptor inhibitor AG-1478 reversed the effect of recombinant tissue plasminogen activator on the phosphoinositide 3-kinase/RAC-alpha serine/threonineprotein kinase/mammalian target of rapamycin pathway.These findings suggest that recombinant tissue plasminogen activator exerts a direct neuroprotective effect on neurons following intracerebral hemorrhage,possibly through activation of the phosphoinositide 3-kinase/RAC-alpha serine/threonine-protein kinase/mammalian target of rapamycin pathway.展开更多
AIM： To construct a recombinant live attenuated Salmonella typhimurium DNA vaccine encoding H pylori ureB gene and mouse IL-2 gene and to detect its immunogenicity in vitro and in vivo. METHODS： Hpylori ureB and mou...AIM： To construct a recombinant live attenuated Salmonella typhimurium DNA vaccine encoding H pylori ureB gene and mouse IL-2 gene and to detect its immunogenicity in vitro and in vivo. METHODS： Hpylori ureB and mouse IL-2 gene fragments were amplified by polymerase chain reaction （PCR） and cloned into pUCmT vector. DNA sequence of the amplified ureB and IL-2 genes was assayed, then cloned into the eukaryotic expression vector pIRES through enzyme digestion and ligation reactions resulting in pIRES-ureB and pIRES-ureB-IL-2. The recombinant plasmids were used to transform competent E. co/i DH5α, and the positive clones were screened by PCR and restriction enzyme digestion. Then, the recombinant pIRES-ureB and pIRES-ureB-IL-2 were used to transform LB5000 and the recombinant plasmids extracted from LB5000 were finally introduced into the final host SL7207. After that, recombinant strains were grown in vitro repeatedly. In order to detect the immunogenicib/of the vaccine in vitro, pIRES-ureB and pIRES-ureB-IL-2 were transfected to COS-7 cells using LipofectamineTM2000, the immunogenicity of expressed UreB and IL-2 proteins was assayed with SDS-PAGE and Western blot. C57BL/6 mice were orally immunized with 1 × 10^8 recombinant attenuated Salmonella typhimurium DNA vaccine. Four weeks after vaccination, mice were challenged with 1 × 10^7 CFU of live Hpylori SS1. Mice were sacrificed and the stomach was isolated for examination of H pylon 4 wk post-challenge. RESULTS： The 1700 base pair ureB gene fragment amplified from the genomic DNA was consistent with the sequence of H pylori ureB by sequence analysis. The amplified 510 base pair fragment was consistent with the sequence of mouse IL-2 in gene bank. It was confirmed by PCR and restriction enzyme digestion that H pylori ureB and mouse IL-2 genes were inserted into the eukaryotic expression vector pIRES. The experiments in vitro showed that stable recombinant live attenuated Salmonella typhimurium DNA vaccine carrying ureB and IL-2 genes was successfully constructed and the specific strips of UreB and IL-2 expressed by recombinant plasmids were detected through Western blot. Study in vivo showed that the positive rate of rapid urease test of the immunized group including ureB and ureB-IL-2 was 37.5% and 12.5% respectively, and was significantly lower than that （100%） in the control group （P 〈 0.01）. CONCLUSION： Recombinant attenuated Salmonella typhimurium DNA vaccine expressing UreB protein and IL-2 protein with immunogenicity can be constructed. It can protect mice against H pylori infection, which may help the development of a human-use H pylori DNA vaccine.展开更多
Rat calcineurin （CAN） A a isoform （Ppp3ca） cDNA recombinant adenovirus vector was constructed in order to explore the effect of CaN on the myocardium apoptosis induced by ischemia-reperfusion injury. Total RNA was...Rat calcineurin （CAN） A a isoform （Ppp3ca） cDNA recombinant adenovirus vector was constructed in order to explore the effect of CaN on the myocardium apoptosis induced by ischemia-reperfusion injury. Total RNA was isolated from the heart of the adult Wistar rht, and Ppp3ca CDS segment of approximate 1.59 kb size was amplified by reverse transcriptional PCR method. Ppp3ca cDNA segment was cloned into pMD18-T Simple vector for sequencing, and the right clone was named T-Ppp3ca. Ppp3ca cDNA segment obtained from T-Ppp3ca was ligated with pShuttle2-IRES-EGFP to construct a recombinant plasmid pShuttle2-Ppp3ca-IRES-EGFP. Ppp3ca-IRES-EG- FP expression cassette containing CMV, Ppp3ca-IRES-EGFP and SV40 polyA DNA fragment （3.97 kb） obtained from pShuttle2-Ppp3ca-IRES-EGFP was connected with pAdeno-X backbone sequence to construct a recombinant plasmid pAdeno Ppp3ca. After being identified by PCR and enzyme digestion, recombinant plasmid pAdeno-Ppp3ca was packaged in HEK293 cells. Supernatant of adenovirus from HEK293 cells was collected after a visible cytopathic effect （CPE） appeared. The DNA of the recombinant adenovirus was extracted with the standard method. The presence of the recombinant adenovirus was verified by PCR. The results showed that sequencing results verified that the PCR product of Ppp3ca gene was identical to GenBank. Agarose electrophoresis showed the bands of recombined plasmid pAdeno-Ppp3ca and the recombinant adenovirus identified by enzyme digestion and PCR were in the right range corresponding with expectation. It was concluded that the recombinant adenovirus carrying rat calcineurin A a （Ppp3ca） cDNA as well as a report gene-enhancer green fluorescent protein gene was successfully constructed in this experiment.展开更多
AIM: To construct a recombinant attenuated Salmonella typhimurium DNA vaccine carrying Helicobacter pylori hpaA gene and to detect its immunogenicity. METHODS: Genomic DNA of the standard H pylori strain 17 874 was is...AIM: To construct a recombinant attenuated Salmonella typhimurium DNA vaccine carrying Helicobacter pylori hpaA gene and to detect its immunogenicity. METHODS: Genomic DNA of the standard H pylori strain 17 874 was isolated as the template, hpaA gene fragment was amplified by polymerase chain reaction (PCR) and cloned into pUCmT vector. DNA sequence of the amplified hpaA gene was assayed, then doned into the eukaryotic expression vector pIRES through enzyme digestion and ligation reactions. The recombinant plasmid was used to transform competent Escherichia coliDH5α, and the positive clones were screened by PCR and restriction enzyme digestion. Then, the recombinant pIRES-hpaA was used to transform LB5000 and the recombinant plasmid isolated from LB5000 was finally used to transform SL7207. After that, the recombinant strain was grown in vitro repeatedly. In order to identify the immunogenicity of the vaccine in vitro, the recombinant pIRES-hpaA was transfected to COS-7 cells using Lipofectamine^(TM)2000, the immunogenicity of expressed HpaA protein was detected with SDS-PAGE and Western blot. RESULTS: The 750-base pair hpaA gene fragment was amplified from the genomic DNA and was consistent with the sequence of H pylori hpaA by sequence analysis. It was confirmed by PCR and restriction enzyme digestion that H pylori hpaA gene was inserted into the eukaryotic expression vector pIRES and a stable recombinant live attenuated Salmonella typhimurium DNA vaccine carrying H pylori hpaA gene was successfully constructed and the specific strip of HpaA expressed by pIRES-hpaA was detected through Western blot. CONCLUSION: The recombinant attenuated Salmonella typhimurium DNA vaccine strain expressing HpaA protein with immunogenicity can be constructed and it may be helpful for further investigating the immune action of DNA vaccine in vivo.展开更多
Objective:To investigate the effect of interleukin-18 (IL-18) on immune response induced by plasmid encoding hepatitis B virus middle protein antigen and to explore new strategies for prophylactic and therapeutic HBV ...Objective:To investigate the effect of interleukin-18 (IL-18) on immune response induced by plasmid encoding hepatitis B virus middle protein antigen and to explore new strategies for prophylactic and therapeutic HBV DNA vaccines.Methods:BALB/c mice were immunized with pCMV-M alone or co-immunized with pcDNA3-18 and pCMV-M and then their sera were collected for analysing anti-HBsAg antibody by ELISA;splenocytes were isolated for detecting specific CTL response and cytokine assay in vitro.Results:The anti-HBs antibody level of mice co-immunized with pcDNA3-18 and pCMV-M was slightly higher than that of mice immunized with pCMV-M alone,but there was not significantly different (P>0.05).Compared with mice injected with pCMV-M, the specific CTL cytotoxity activity of mice immunized with pcDNA3-18 and pCMV-M was significantly enhanced (P<0.05) and the level of IFN-γ in supernatant of splenocytes cultured with HBsAg in vitro was significantly elevated (P<0.05) while the level of IL-4 had no significant difference (P>0.05).Conclusion:The plasmid encoding IL-18 together with HBV M gene DNA vaccines may enhance specific TH1 cells and CTL cellular immune response induced in mice, so that IL-18 is a promising immune adjuvant.展开更多
Mycobacterium tuberculosis 6-kDa early secretory antigenic target （ESAT-6） is a dominant target antigen for cell-mediated immunity in the early phase of tuberculosis. The fms-like tyrosine kinase 3 ligand （FL） tha...Mycobacterium tuberculosis 6-kDa early secretory antigenic target （ESAT-6） is a dominant target antigen for cell-mediated immunity in the early phase of tuberculosis. The fms-like tyrosine kinase 3 ligand （FL） that induces potent immune response has been used as an adjuvant in vaccine development. In this study, a new recombinant plasmid （plRES-epitope-peptides-FL） encoding three T cell epitopes of ESAT-6 and FL was constructed, and the immunogenicity of the DNA vaccine was assessed in C57BL/6 mice immunized with the plasmid DNA vaccine. Additionally, a strategy of intramuscular injection with the DNA vaccine （prime） and intranasal administration of the epitope peptides （boost） was employed to induce higher immune reaction of the mice. The results showed that mice vaccinated with the recombinant plasmid DNA vaccine and boosted with the peptides not only increased the levels of Thl cytokines （IFN-γ and IL-12）, the number of IFN-γ＋ T cells and activities of cytotoxic T lymphocytes as well as IgG, but also enhanced protection against Mycobacterium tuberculosis challenge. In conclusion, these data indicate that the novel recombinant plRES-epitope-peptides-FL plasmid is a useful DNA vaccine for pre- venting Mycobacterium tuberculosis infection.展开更多
BACKGROUND Patients with acute-on-chronic liver failure(ACLF)have a high mortality rate,poor prognosis,and often experience concurrent thrombocytopenia and bleeding events.AIM To evaluate the efficacy and safety of re...BACKGROUND Patients with acute-on-chronic liver failure(ACLF)have a high mortality rate,poor prognosis,and often experience concurrent thrombocytopenia and bleeding events.AIM To evaluate the efficacy and safety of recombinant human thrombopoietin(rhTPO)in patients with ACLF with concomitant severe thrombocytopenia.METHODS This was a prospective,open-label study.We assigned 70 ACLF patients with severe thrombocytopenia into the rhTPO group and control group,with 35 patients in each group.Patients in the rhTPO group received subcutaneous injections of rhTPO at a dose of 15000 IU/day for 7 consecutive days,while patients in the control group did not receive rhTPO treatment.The primary endpoint was the proportion of patients with platelet count>50×10^(9)/L on day 14.RESULTS The proportion of patients with platelet count>50×10^(9)/L on day 14 was 60.7%in the rhTPO group,which was significantly higher than that(12.0%)in the control group(P<0.001).The platelet count in the rhTPO group on day 14 was 64×10^(9)/L,exceeding the baseline of 28×10^(9)/L.Compared to the control group,the rhTPO group exhibited a significant increase in platelet count from baseline(P<0.05).Model for end-stage liver disease score,albumin level and international normalized ratio improved significantly from baseline on day 14 after rhTPO injection.The concentrations of serum thrombopoietin and hepatocyte growth factor in the rhTPO group after 7 days were 143.7 and 195.4 pg/mL,respectively,showing a significant increase from baseline(P<0.05).Eight(22.9%)patients had bleeding events in the control group compared with four(11.4%)in the rhTPO group.The incidence of 90-day mortality was also higher in the control group(6,17.1%)than that in the rhTPO group(3,8.6%).CONCLUSION rhTPO significantly increased the platelet count in ACLF patients with thrombocytopenia and reduce the occurrence of bleeding events,with a good safety profile.展开更多
[Objective]To design and express a recombinant protein rMKIBV incorporating confirmed antigenic epitopes of infectious bronchitis virus(IBV)as a vaccine to provide comprehensive protection.Additionally,it explores the...[Objective]To design and express a recombinant protein rMKIBV incorporating confirmed antigenic epitopes of infectious bronchitis virus(IBV)as a vaccine to provide comprehensive protection.Additionally,it explores the potential of polyclonal yolk antibodies(IgY)harvested from laying hens immunized with the rMKIBV vaccine in the prevention and control of IBV.[Methods]The antigenic epitope sequences of IBV,obtained from online databases,were compared with sequences of representative IBV strains from GenBank.Flexible peptides were designed to link all antigenic peptides.The constructed amino acid sequence was analyzed,reverse-translated,codon-optimized,and then inserted into the pET-28a(+)cloning vector.The recombinant vector was introduced into Escherichia coli for expression.The purified,desalted,and endotoxin-removed rMKIBV protein was used as a vaccine to immunize animals for investigation of its immunogenicity and ability to stimulate specific IgY production in laying hens.[Results]The retrieved IBV antigenic epitope sequences showed high similarity with the published N and S protein sequences of 22 representative IBV strains.The predicted isoelectric point and molecular weight of rMKIBV were 10.25 and 63.39 kDa,respectively.The secondary structure of rMKIBV included a high proportion of random coils,which suggested strong antigenicity.High-purity rMKIBV was obtained from E.coli transformed with the recombinant plasmid pET-28a-mkibv.This protein specifically bound to anti-His-tag antibodies,N protein antibodies,and S protein antibodies.The mice immunized with this protein showed increases in the spleen index(P<0.05),elevations in the levels of serum-specific IgG antibodies(P<0.01)and IFN-γ(P<0.05),and no significant change in the IL-2 level.Immunized laying hens successfully produced IgY in egg yolks,with specific IgY antibody levels significantly increasing.Moreover,the IgY antibody titer gradually rose after immunization,reaching the peak after about 50 days and then gradually declining to reach a stable level.[Conclusion]We successfully constructed and expressed the recombinant protein rMKIBV.The protein demonstrated good immunogenicity,stimulating specific antibody production in both mice and laying hens.Notably,the IgY extracted from the yolks of immunized laying hens offers a novel approach to IBV prevention and control.These findings hold significant scientific and practical value for the development of vaccines against IBV.展开更多
Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life ...Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life of patients.To date,there are no viable treatment options for postoperative cognitive dysfunction.The identification of postoperative cognitive dysfunction hub genes could provide new research directions and therapeutic targets for future research.To identify the signaling mechanisms contributing to postoperative cognitive dysfunction,we first conducted Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of the Gene Expression Omnibus GSE95426 dataset,which consists of mRNAs and long non-coding RNAs differentially expressed in mouse hippocampus3 days after tibial fracture.The dataset was enriched in genes associated with the biological process"regulation of immune cells,"of which Chill was identified as a hub gene.Therefore,we investigated the contribution of chitinase-3-like protein 1 protein expression changes to postoperative cognitive dysfunction in the mouse model of tibial fractu re surgery.Mice were intraperitoneally injected with vehicle or recombinant chitinase-3-like protein 124 hours post-surgery,and the injection groups were compared with untreated control mice for learning and memory capacities using the Y-maze and fear conditioning tests.In addition,protein expression levels of proinflammatory factors(interleukin-1βand inducible nitric oxide synthase),M2-type macrophage markers(CD206 and arginase-1),and cognition-related proteins(brain-derived neurotropic factor and phosphorylated NMDA receptor subunit NR2B)were measured in hippocampus by western blotting.Treatment with recombinant chitinase-3-like protein 1 prevented surgery-induced cognitive impairment,downregulated interleukin-1βand nducible nitric oxide synthase expression,and upregulated CD206,arginase-1,pNR2B,and brain-derived neurotropic factor expression compared with vehicle treatment.Intraperitoneal administration of the specific ERK inhibitor PD98059 diminished the effects of recombinant chitinase-3-like protein 1.Collectively,our findings suggest that recombinant chitinase-3-like protein 1 ameliorates surgery-induced cognitive decline by attenuating neuroinflammation via M2 microglial polarization in the hippocampus.Therefore,recombinant chitinase-3-like protein1 may have therapeutic potential fo r postoperative cognitive dysfunction.展开更多
To study the expression characteristic of Japanese encephalitis virus (JEV) prME and E proteins and the efficacy of DNA immunization by different recombinant plasmids containing JEV prME (2001 bp) and E (1500 bp) gene...To study the expression characteristic of Japanese encephalitis virus (JEV) prME and E proteins and the efficacy of DNA immunization by different recombinant plasmids containing JEV prME (2001 bp) and E (1500 bp) genes, two recombinants (pJME and pJE) containing JEV prME and E genes fused with FLAG were constructed and then transfected into HepG2 and COS-1 cells by liposome fusion. The expression feature of FLAG-prME (about 72 kDa) and FLAG-E (about 54 kDa) proteins in transfected cells were analyzed by Western blot and two antibody systems (anti-FLAG and anti-E). BALB/c mice were immunized with 100 μg of two kinds of recombinants by intramuscular injection, and JEV JaGAr-01 strains (10 5 PFU/100 μl)were given to BALB/c mice by intraperioneal injection 3 wk after twice DNA immunization by a lethal virus challenge. BALB/c mice were observed for 21 days after challenge. 80% plaque reduction neutralization test was performed to titrate neutralization antibody before and after viral challenge. It was found that the expression of proteins associated with pJME and pJE was determined in transfected cells with anti-FLAG and a new protein of 11 kDa was detected in HepG2 and COS-1 cells transfected with pJME. Only E (53 kDa) protein was identified as transfected with pJME using anti-E. Higher level of neutralization antibodies and the efficacy of protective immunity were induced with pJME immunization, and were similar to those induced by inactivated Japanese encephalitis vaccine, but were better than those induced with pJE. It concludes that the expression level from prM to E proteins of JEV is different in vitro, and the in vitro expression efficiency of pJME was better than that of pJE. FLAG-prME protein expressed by pJME could be cleaved by peptidase from host. The efficacy of DNA immunization is correlated to the expression characterization of related proteins expressed in vitro.展开更多
Single-stranded DNA-binding proteins(SSBs)play essential roles in the replication,recombination and repair processes of organellar DNA molecules.In Arabidopsis thaliana,SSBs are encoded by a small family of two genes(...Single-stranded DNA-binding proteins(SSBs)play essential roles in the replication,recombination and repair processes of organellar DNA molecules.In Arabidopsis thaliana,SSBs are encoded by a small family of two genes(SSB1 and SSB2).However,the functional divergence of these two SSB copies in plants remains largely unknown,and detailed studies regarding their roles in the replication and recombination of organellar genomes are still incomplete.In this study,phylogenetic,gene structure and protein motif analyses all suggested that SSB1 and SSB2 probably diverged during the early evolution of seed plants.Based on accurate long-read sequencing results,ssb1 and ssb2 mutants had decreased copy numbers for both mitochondrial DNA(mtDNA)and plastid DNA(ptDNA),accompanied by a slight increase in structural rearrangements mediated by intermediate-sized repeats in mt genome and small-scale variants in both genomes.Our findings provide an important foundation for further investigating the effects of DNA dosage in the regulation of mutation frequencies in plant organellar genomes.展开更多
Early diagnosis of leptospirosis of pulmonary diffuse hernorrhage type (PDH) is of crucial importance in saving patients. To develop a sensitive and specific methed for diagnosis, a genomic library of the main pathoge...Early diagnosis of leptospirosis of pulmonary diffuse hernorrhage type (PDH) is of crucial importance in saving patients. To develop a sensitive and specific methed for diagnosis, a genomic library of the main pathogen of PDH, L. interrogans serovar lai strain 017, was constructed with the plasmid vector PUC9. Recombinant plasmids which have hornologous fragments of pathogenic leptospires were screened from the bank. A recombinant plasmid,designated PCX7, could detect 1.7 kb fragment of strain 017, 9. 0 kb of strain 601 and 30. 0 kb of strain Hebdomadis, respectively, without cross hybridization with nonpathogenic leptospires such as L. biflexa strain Patoc I and hoptonema illini. The recombinant plasmid PCX7 could detect pathogenic leptospires which are the main pathogens endemic to Sichuan Province.展开更多
文摘The published article titled“Truncated Bid Overexpression Induced by Recombinant Adenovirus Cre/LoxP System Suppresses the Tumorigenic Potential of CD133+Ovarian Cancer Stem Cells”has been retracted from Oncology Research,Vol.25,No.4,2017,pp.595–603.
基金supported by the National Natural Science Foundation of China,Nos.92148206,82071330(both to ZT)a grant from the Major Program of Hubei Province,No.2023BAA005(to ZT)+1 种基金a grant from the Key Research and Discovery Program of Hubei Province,No.2021BCA109(to ZT)the Research Foundation of Tongji Hospital,No.2022B37(to PZ)。
文摘Recombinant tissue plasminogen activator is commonly used for hematoma evacuation in minimally invasive surgery following intracerebral hemorrhage.However,during minimally invasive surgery,recombinant tissue plasminogen activator may come into contact with brain tissue.Therefore,a thorough assessment of its safety is required.In this study,we established a mouse model of intracerebral hemorrhage induced by type VII collagenase.We observed that the administration of recombinant tissue plasminogen activator without hematoma aspiration significantly improved the neurological function of mice with intracerebral hemorrhage,reduced pathological damage,and lowered the levels of apoptosis and autophagy in the tissue surrounding the hematoma.In an in vitro model of intracerebral hemorrhage using primary cortical neurons induced by hemin,the administration of recombinant tissue plasminogen activator suppressed neuronal apoptosis,autophagy,and endoplasmic reticulum stress.Transcriptome sequencing analysis revealed that recombinant tissue plasminogen activator upregulated the phosphoinositide 3-kinase/RAC-alpha serine/threonine-protein kinase/mammalian target of rapamycin pathway in neurons.Moreover,the phosphoinositide 3-kinase inhibitor LY294002 abrogated the neuroprotective effects of recombinant tissue plasminogen activator in inhibiting excessive apoptosis,autophagy,and endoplasmic reticulum stress.Furthermore,to specify the domain of recombinant tissue plasminogen activator responsible for its neuroprotective effects,various inhibitors were used to target distinct domains.It has been revealed that the epidermal growth factor receptor inhibitor AG-1478 reversed the effect of recombinant tissue plasminogen activator on the phosphoinositide 3-kinase/RAC-alpha serine/threonineprotein kinase/mammalian target of rapamycin pathway.These findings suggest that recombinant tissue plasminogen activator exerts a direct neuroprotective effect on neurons following intracerebral hemorrhage,possibly through activation of the phosphoinositide 3-kinase/RAC-alpha serine/threonine-protein kinase/mammalian target of rapamycin pathway.
基金the National Natural Science Foundation of China, No. 30170427
文摘AIM： To construct a recombinant live attenuated Salmonella typhimurium DNA vaccine encoding H pylori ureB gene and mouse IL-2 gene and to detect its immunogenicity in vitro and in vivo. METHODS： Hpylori ureB and mouse IL-2 gene fragments were amplified by polymerase chain reaction （PCR） and cloned into pUCmT vector. DNA sequence of the amplified ureB and IL-2 genes was assayed, then cloned into the eukaryotic expression vector pIRES through enzyme digestion and ligation reactions resulting in pIRES-ureB and pIRES-ureB-IL-2. The recombinant plasmids were used to transform competent E. co/i DH5α, and the positive clones were screened by PCR and restriction enzyme digestion. Then, the recombinant pIRES-ureB and pIRES-ureB-IL-2 were used to transform LB5000 and the recombinant plasmids extracted from LB5000 were finally introduced into the final host SL7207. After that, recombinant strains were grown in vitro repeatedly. In order to detect the immunogenicib/of the vaccine in vitro, pIRES-ureB and pIRES-ureB-IL-2 were transfected to COS-7 cells using LipofectamineTM2000, the immunogenicity of expressed UreB and IL-2 proteins was assayed with SDS-PAGE and Western blot. C57BL/6 mice were orally immunized with 1 × 10^8 recombinant attenuated Salmonella typhimurium DNA vaccine. Four weeks after vaccination, mice were challenged with 1 × 10^7 CFU of live Hpylori SS1. Mice were sacrificed and the stomach was isolated for examination of H pylon 4 wk post-challenge. RESULTS： The 1700 base pair ureB gene fragment amplified from the genomic DNA was consistent with the sequence of H pylori ureB by sequence analysis. The amplified 510 base pair fragment was consistent with the sequence of mouse IL-2 in gene bank. It was confirmed by PCR and restriction enzyme digestion that H pylori ureB and mouse IL-2 genes were inserted into the eukaryotic expression vector pIRES. The experiments in vitro showed that stable recombinant live attenuated Salmonella typhimurium DNA vaccine carrying ureB and IL-2 genes was successfully constructed and the specific strips of UreB and IL-2 expressed by recombinant plasmids were detected through Western blot. Study in vivo showed that the positive rate of rapid urease test of the immunized group including ureB and ureB-IL-2 was 37.5% and 12.5% respectively, and was significantly lower than that （100%） in the control group （P 〈 0.01）. CONCLUSION： Recombinant attenuated Salmonella typhimurium DNA vaccine expressing UreB protein and IL-2 protein with immunogenicity can be constructed. It can protect mice against H pylori infection, which may help the development of a human-use H pylori DNA vaccine.
文摘Rat calcineurin （CAN） A a isoform （Ppp3ca） cDNA recombinant adenovirus vector was constructed in order to explore the effect of CaN on the myocardium apoptosis induced by ischemia-reperfusion injury. Total RNA was isolated from the heart of the adult Wistar rht, and Ppp3ca CDS segment of approximate 1.59 kb size was amplified by reverse transcriptional PCR method. Ppp3ca cDNA segment was cloned into pMD18-T Simple vector for sequencing, and the right clone was named T-Ppp3ca. Ppp3ca cDNA segment obtained from T-Ppp3ca was ligated with pShuttle2-IRES-EGFP to construct a recombinant plasmid pShuttle2-Ppp3ca-IRES-EGFP. Ppp3ca-IRES-EG- FP expression cassette containing CMV, Ppp3ca-IRES-EGFP and SV40 polyA DNA fragment （3.97 kb） obtained from pShuttle2-Ppp3ca-IRES-EGFP was connected with pAdeno-X backbone sequence to construct a recombinant plasmid pAdeno Ppp3ca. After being identified by PCR and enzyme digestion, recombinant plasmid pAdeno-Ppp3ca was packaged in HEK293 cells. Supernatant of adenovirus from HEK293 cells was collected after a visible cytopathic effect （CPE） appeared. The DNA of the recombinant adenovirus was extracted with the standard method. The presence of the recombinant adenovirus was verified by PCR. The results showed that sequencing results verified that the PCR product of Ppp3ca gene was identical to GenBank. Agarose electrophoresis showed the bands of recombined plasmid pAdeno-Ppp3ca and the recombinant adenovirus identified by enzyme digestion and PCR were in the right range corresponding with expectation. It was concluded that the recombinant adenovirus carrying rat calcineurin A a （Ppp3ca） cDNA as well as a report gene-enhancer green fluorescent protein gene was successfully constructed in this experiment.
基金Supported by the National Natural Science Foundation of China,No. 30170427
文摘AIM: To construct a recombinant attenuated Salmonella typhimurium DNA vaccine carrying Helicobacter pylori hpaA gene and to detect its immunogenicity. METHODS: Genomic DNA of the standard H pylori strain 17 874 was isolated as the template, hpaA gene fragment was amplified by polymerase chain reaction (PCR) and cloned into pUCmT vector. DNA sequence of the amplified hpaA gene was assayed, then doned into the eukaryotic expression vector pIRES through enzyme digestion and ligation reactions. The recombinant plasmid was used to transform competent Escherichia coliDH5α, and the positive clones were screened by PCR and restriction enzyme digestion. Then, the recombinant pIRES-hpaA was used to transform LB5000 and the recombinant plasmid isolated from LB5000 was finally used to transform SL7207. After that, the recombinant strain was grown in vitro repeatedly. In order to identify the immunogenicity of the vaccine in vitro, the recombinant pIRES-hpaA was transfected to COS-7 cells using Lipofectamine^(TM)2000, the immunogenicity of expressed HpaA protein was detected with SDS-PAGE and Western blot. RESULTS: The 750-base pair hpaA gene fragment was amplified from the genomic DNA and was consistent with the sequence of H pylori hpaA by sequence analysis. It was confirmed by PCR and restriction enzyme digestion that H pylori hpaA gene was inserted into the eukaryotic expression vector pIRES and a stable recombinant live attenuated Salmonella typhimurium DNA vaccine carrying H pylori hpaA gene was successfully constructed and the specific strip of HpaA expressed by pIRES-hpaA was detected through Western blot. CONCLUSION: The recombinant attenuated Salmonella typhimurium DNA vaccine strain expressing HpaA protein with immunogenicity can be constructed and it may be helpful for further investigating the immune action of DNA vaccine in vivo.
文摘Objective:To investigate the effect of interleukin-18 (IL-18) on immune response induced by plasmid encoding hepatitis B virus middle protein antigen and to explore new strategies for prophylactic and therapeutic HBV DNA vaccines.Methods:BALB/c mice were immunized with pCMV-M alone or co-immunized with pcDNA3-18 and pCMV-M and then their sera were collected for analysing anti-HBsAg antibody by ELISA;splenocytes were isolated for detecting specific CTL response and cytokine assay in vitro.Results:The anti-HBs antibody level of mice co-immunized with pcDNA3-18 and pCMV-M was slightly higher than that of mice immunized with pCMV-M alone,but there was not significantly different (P>0.05).Compared with mice injected with pCMV-M, the specific CTL cytotoxity activity of mice immunized with pcDNA3-18 and pCMV-M was significantly enhanced (P<0.05) and the level of IFN-γ in supernatant of splenocytes cultured with HBsAg in vitro was significantly elevated (P<0.05) while the level of IL-4 had no significant difference (P>0.05).Conclusion:The plasmid encoding IL-18 together with HBV M gene DNA vaccines may enhance specific TH1 cells and CTL cellular immune response induced in mice, so that IL-18 is a promising immune adjuvant.
基金supported by the Natural Scientific Fund (09KJA310002DG216D50162011NJMU263 and 11JC005) of China
文摘Mycobacterium tuberculosis 6-kDa early secretory antigenic target （ESAT-6） is a dominant target antigen for cell-mediated immunity in the early phase of tuberculosis. The fms-like tyrosine kinase 3 ligand （FL） that induces potent immune response has been used as an adjuvant in vaccine development. In this study, a new recombinant plasmid （plRES-epitope-peptides-FL） encoding three T cell epitopes of ESAT-6 and FL was constructed, and the immunogenicity of the DNA vaccine was assessed in C57BL/6 mice immunized with the plasmid DNA vaccine. Additionally, a strategy of intramuscular injection with the DNA vaccine （prime） and intranasal administration of the epitope peptides （boost） was employed to induce higher immune reaction of the mice. The results showed that mice vaccinated with the recombinant plasmid DNA vaccine and boosted with the peptides not only increased the levels of Thl cytokines （IFN-γ and IL-12）, the number of IFN-γ＋ T cells and activities of cytotoxic T lymphocytes as well as IgG, but also enhanced protection against Mycobacterium tuberculosis challenge. In conclusion, these data indicate that the novel recombinant plRES-epitope-peptides-FL plasmid is a useful DNA vaccine for pre- venting Mycobacterium tuberculosis infection.
基金Supported by Tianjin Key Medical Discipline(Specialty)Construction Project,No.TJYXZDXK-034A.
文摘BACKGROUND Patients with acute-on-chronic liver failure(ACLF)have a high mortality rate,poor prognosis,and often experience concurrent thrombocytopenia and bleeding events.AIM To evaluate the efficacy and safety of recombinant human thrombopoietin(rhTPO)in patients with ACLF with concomitant severe thrombocytopenia.METHODS This was a prospective,open-label study.We assigned 70 ACLF patients with severe thrombocytopenia into the rhTPO group and control group,with 35 patients in each group.Patients in the rhTPO group received subcutaneous injections of rhTPO at a dose of 15000 IU/day for 7 consecutive days,while patients in the control group did not receive rhTPO treatment.The primary endpoint was the proportion of patients with platelet count>50×10^(9)/L on day 14.RESULTS The proportion of patients with platelet count>50×10^(9)/L on day 14 was 60.7%in the rhTPO group,which was significantly higher than that(12.0%)in the control group(P<0.001).The platelet count in the rhTPO group on day 14 was 64×10^(9)/L,exceeding the baseline of 28×10^(9)/L.Compared to the control group,the rhTPO group exhibited a significant increase in platelet count from baseline(P<0.05).Model for end-stage liver disease score,albumin level and international normalized ratio improved significantly from baseline on day 14 after rhTPO injection.The concentrations of serum thrombopoietin and hepatocyte growth factor in the rhTPO group after 7 days were 143.7 and 195.4 pg/mL,respectively,showing a significant increase from baseline(P<0.05).Eight(22.9%)patients had bleeding events in the control group compared with four(11.4%)in the rhTPO group.The incidence of 90-day mortality was also higher in the control group(6,17.1%)than that in the rhTPO group(3,8.6%).CONCLUSION rhTPO significantly increased the platelet count in ACLF patients with thrombocytopenia and reduce the occurrence of bleeding events,with a good safety profile.
文摘[Objective]To design and express a recombinant protein rMKIBV incorporating confirmed antigenic epitopes of infectious bronchitis virus(IBV)as a vaccine to provide comprehensive protection.Additionally,it explores the potential of polyclonal yolk antibodies(IgY)harvested from laying hens immunized with the rMKIBV vaccine in the prevention and control of IBV.[Methods]The antigenic epitope sequences of IBV,obtained from online databases,were compared with sequences of representative IBV strains from GenBank.Flexible peptides were designed to link all antigenic peptides.The constructed amino acid sequence was analyzed,reverse-translated,codon-optimized,and then inserted into the pET-28a(+)cloning vector.The recombinant vector was introduced into Escherichia coli for expression.The purified,desalted,and endotoxin-removed rMKIBV protein was used as a vaccine to immunize animals for investigation of its immunogenicity and ability to stimulate specific IgY production in laying hens.[Results]The retrieved IBV antigenic epitope sequences showed high similarity with the published N and S protein sequences of 22 representative IBV strains.The predicted isoelectric point and molecular weight of rMKIBV were 10.25 and 63.39 kDa,respectively.The secondary structure of rMKIBV included a high proportion of random coils,which suggested strong antigenicity.High-purity rMKIBV was obtained from E.coli transformed with the recombinant plasmid pET-28a-mkibv.This protein specifically bound to anti-His-tag antibodies,N protein antibodies,and S protein antibodies.The mice immunized with this protein showed increases in the spleen index(P<0.05),elevations in the levels of serum-specific IgG antibodies(P<0.01)and IFN-γ(P<0.05),and no significant change in the IL-2 level.Immunized laying hens successfully produced IgY in egg yolks,with specific IgY antibody levels significantly increasing.Moreover,the IgY antibody titer gradually rose after immunization,reaching the peak after about 50 days and then gradually declining to reach a stable level.[Conclusion]We successfully constructed and expressed the recombinant protein rMKIBV.The protein demonstrated good immunogenicity,stimulating specific antibody production in both mice and laying hens.Notably,the IgY extracted from the yolks of immunized laying hens offers a novel approach to IBV prevention and control.These findings hold significant scientific and practical value for the development of vaccines against IBV.
基金supported by the National Natural Science Foundation of China,Nos.81730033,82171193(to XG)the Key Talent Project for Strengthening Health during the 13^(th)Five-Year Plan Period,No.ZDRCA2016069(to XG)+1 种基金the National Key R&D Program of China,No.2018YFC2001901(to XG)Jiangsu Provincial Medical Key Discipline,No.ZDXK202232(to XG)。
文摘Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life of patients.To date,there are no viable treatment options for postoperative cognitive dysfunction.The identification of postoperative cognitive dysfunction hub genes could provide new research directions and therapeutic targets for future research.To identify the signaling mechanisms contributing to postoperative cognitive dysfunction,we first conducted Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of the Gene Expression Omnibus GSE95426 dataset,which consists of mRNAs and long non-coding RNAs differentially expressed in mouse hippocampus3 days after tibial fracture.The dataset was enriched in genes associated with the biological process"regulation of immune cells,"of which Chill was identified as a hub gene.Therefore,we investigated the contribution of chitinase-3-like protein 1 protein expression changes to postoperative cognitive dysfunction in the mouse model of tibial fractu re surgery.Mice were intraperitoneally injected with vehicle or recombinant chitinase-3-like protein 124 hours post-surgery,and the injection groups were compared with untreated control mice for learning and memory capacities using the Y-maze and fear conditioning tests.In addition,protein expression levels of proinflammatory factors(interleukin-1βand inducible nitric oxide synthase),M2-type macrophage markers(CD206 and arginase-1),and cognition-related proteins(brain-derived neurotropic factor and phosphorylated NMDA receptor subunit NR2B)were measured in hippocampus by western blotting.Treatment with recombinant chitinase-3-like protein 1 prevented surgery-induced cognitive impairment,downregulated interleukin-1βand nducible nitric oxide synthase expression,and upregulated CD206,arginase-1,pNR2B,and brain-derived neurotropic factor expression compared with vehicle treatment.Intraperitoneal administration of the specific ERK inhibitor PD98059 diminished the effects of recombinant chitinase-3-like protein 1.Collectively,our findings suggest that recombinant chitinase-3-like protein 1 ameliorates surgery-induced cognitive decline by attenuating neuroinflammation via M2 microglial polarization in the hippocampus.Therefore,recombinant chitinase-3-like protein1 may have therapeutic potential fo r postoperative cognitive dysfunction.
基金This research was supported by a grant for project research from high Technology center of Kanazawa Medical University(H2000 2)
文摘To study the expression characteristic of Japanese encephalitis virus (JEV) prME and E proteins and the efficacy of DNA immunization by different recombinant plasmids containing JEV prME (2001 bp) and E (1500 bp) genes, two recombinants (pJME and pJE) containing JEV prME and E genes fused with FLAG were constructed and then transfected into HepG2 and COS-1 cells by liposome fusion. The expression feature of FLAG-prME (about 72 kDa) and FLAG-E (about 54 kDa) proteins in transfected cells were analyzed by Western blot and two antibody systems (anti-FLAG and anti-E). BALB/c mice were immunized with 100 μg of two kinds of recombinants by intramuscular injection, and JEV JaGAr-01 strains (10 5 PFU/100 μl)were given to BALB/c mice by intraperioneal injection 3 wk after twice DNA immunization by a lethal virus challenge. BALB/c mice were observed for 21 days after challenge. 80% plaque reduction neutralization test was performed to titrate neutralization antibody before and after viral challenge. It was found that the expression of proteins associated with pJME and pJE was determined in transfected cells with anti-FLAG and a new protein of 11 kDa was detected in HepG2 and COS-1 cells transfected with pJME. Only E (53 kDa) protein was identified as transfected with pJME using anti-E. Higher level of neutralization antibodies and the efficacy of protective immunity were induced with pJME immunization, and were similar to those induced by inactivated Japanese encephalitis vaccine, but were better than those induced with pJE. It concludes that the expression level from prM to E proteins of JEV is different in vitro, and the in vitro expression efficiency of pJME was better than that of pJE. FLAG-prME protein expressed by pJME could be cleaved by peptidase from host. The efficacy of DNA immunization is correlated to the expression characterization of related proteins expressed in vitro.
基金supported by grants from the National Natural Science Foundation of China(32170238,32400191)Guangdong Basic and Applied Basic Research Foundation(2023A1515111029)+2 种基金the Science,Technology and Innovation Commission of Shenzhen Municipality(RCYX20200714114538196)the Chinese Academy of Agricultural Sciences Elite Youth Program(grant 110243160001007)the Guangdong Pearl River Talent Program(2021QN02N792)。
文摘Single-stranded DNA-binding proteins(SSBs)play essential roles in the replication,recombination and repair processes of organellar DNA molecules.In Arabidopsis thaliana,SSBs are encoded by a small family of two genes(SSB1 and SSB2).However,the functional divergence of these two SSB copies in plants remains largely unknown,and detailed studies regarding their roles in the replication and recombination of organellar genomes are still incomplete.In this study,phylogenetic,gene structure and protein motif analyses all suggested that SSB1 and SSB2 probably diverged during the early evolution of seed plants.Based on accurate long-read sequencing results,ssb1 and ssb2 mutants had decreased copy numbers for both mitochondrial DNA(mtDNA)and plastid DNA(ptDNA),accompanied by a slight increase in structural rearrangements mediated by intermediate-sized repeats in mt genome and small-scale variants in both genomes.Our findings provide an important foundation for further investigating the effects of DNA dosage in the regulation of mutation frequencies in plant organellar genomes.
文摘Early diagnosis of leptospirosis of pulmonary diffuse hernorrhage type (PDH) is of crucial importance in saving patients. To develop a sensitive and specific methed for diagnosis, a genomic library of the main pathogen of PDH, L. interrogans serovar lai strain 017, was constructed with the plasmid vector PUC9. Recombinant plasmids which have hornologous fragments of pathogenic leptospires were screened from the bank. A recombinant plasmid,designated PCX7, could detect 1.7 kb fragment of strain 017, 9. 0 kb of strain 601 and 30. 0 kb of strain Hebdomadis, respectively, without cross hybridization with nonpathogenic leptospires such as L. biflexa strain Patoc I and hoptonema illini. The recombinant plasmid PCX7 could detect pathogenic leptospires which are the main pathogens endemic to Sichuan Province.
