Preparation of recombinant PTD-HSP27 and verification of its ability to penetrate the cell membrane of human lens epithelial cells and rabbit cor-nea / 中国病理生理杂志

AIM: To construct the prokaryotic expression system containing protein transduction domain (PTD) with heat shock protein 27 (HSP27) in order to prepare and purify the recombinant protein , and to verify whether the recombinant protein PTD-HSP27 has the ability to penetrate the human lens epithelial cell ( HLEC) membrane and the rabbit cornea.METHODS:The plasmid pKYB-PTD-HSPB1-6His was constructed by the technique of overlap extension PCR.The plasmid was transformed and PTD-HSP27 was purified through nickel affinity chromatography column and identi-fied by Western blotting.PTD-HSP27-6His was labeled with the fluorescein isothiocyanate (FITC).The penetrating ability of PTD-HSP27 into HLECs and rabbit cornea was tested .RESULTS:The recombinant PTD-HSP27 plasmid was success-fully cloned and effectively expressed .The correctness of the recombinant protein PTD-HSP27 was demonstrated .Fluores-cence microscopic examination showed that PTD-HSP27-FITC was internalized by HLECs .Fluorescent labeled PTD-HSP27 was then observed in the rabbit aqueous humor .CONCLUSION:The recombined gene PTD-HSPB1 was constructed by o-verlap extension PCR technique and the PTD-HSP27 fusion protein was prepared and purified by nickel affinity chromatog-raphy column.Using the technique of PTD-fusion protein, HSP27 was transduced into HLECs and passed through the cor-nea .

Expression and bioactivity of protein transduction domain-paraoxonase 1 fusion protein / 国际药学研究杂志

Objective Using silkworm expression system to express human serum paraoxonase 1 (PON1) fusion protein with protein transduction domain Pll and to study its biological activity of fighting aginst the toxicity of dichlorvos. Methods P11-PON1 fusion gene was constructed in cloning sites of silkworm pFastBac 5B vector, the vector and was transformed to silkworm DH10BmBac competent cells. Virus particles and 5 instar silkworm was infected 96 hours after infection, parasites were collected and lyophilized crushed and preserved at -80 7. The protien was dissolved, sonicated and centrifuged before used. Supernatants were harvested. The fusion protein P11-PON1 proportion of the total protein was analyzed with SDS-PAGE electrophoresis and protein content was calculated. Mouse and zebrafish models were used to evaluate P11-PON1 fusion protein bioactivity. Each mouse was treated with 1 mg P11-PON1 fusion protein via intragastric or rectal administration. 0 and 3 hours after administration, 20 mg/kg dichlorvos were injected intraperitoneally. The status of intoxication was observed and the survival rate was scored. P11-P0N1 fusion protein with concentrations of 1, 2.5, 5, 10, 20 mg/L was dissolved in zebrafish breeding water respectively. 0 and 3 hours after exposing dichlorvos were added with a final concentration of 50 mg/L. Observe their behavioral change.The survival rate of zebrafish was recorded. Results The content of P11-P0N1 fusion protein was 8% of silkworm total protein. In mice experiments, P11-P0N1 fusion protein by intragastric adminstration did not increase the survival of mouse. By intraperitoneal injection with dichlorvos 0h after rectal adminstration with protein,the survival rate of mouse did not significantly increase. In contrast, the mouse intraperitoneally injected with dichlorvos 3h after adminstration with protein, the survival rate increased extremely significantly (P < 0.01). In zebrafish experiments, the zebrafish exposed to dichlorvos 0 h after adminstration with protein, the survival rate was not significantly improved, while exposed to dichlorvos 3h after admindtration, the survival rate significantly increased. The survival rate of 20, 10, 5 mg/L group were 62.5%, 62.5% and 50% respectively at 24 h time point, compared to the control group. The survival rate increased extremely significantly (P < 0.01). 2.5 mg/ L group was 41.7%, with the survival rate increasing significantly (P < 0.05). However, the survival rate of 1 mg/L group was 16.7%, compared to the control group. The increase had no sistatistical significance. Conclusion The PTD-containing P0N1 fusion protein can be expressed in silkworm. Pretreatment with the fusion protein in mice and zebrafish decreased the toxicity of dichlorvos.

Effect of transducted heme oxygenase-1 protein on rat brain ischemia-reperfusion injury / 中国药理学通报

Aim To investigate the effect of transduct-ed-hemeoxygenase-1 ( HO-1 ) protein on brain ischemi-a-reperfusion ( I/R ) rat hippocampal neurons injury. Methods 11 R ( arginine residues )-fused HO-1 pro-tein was established and 50 male Mongolian gerbils were randomly divided into 5 groups ( n=10 ):I/R ( control group ) , I/R + 5 mg · kg-1 saline group ( group S ) , I/R + 5 mg · kg-1 11 R group ( group R), I/R + 5mg·kg-1 11R-HO-1 group (group H1) and I/R + 25 mg · kg-1 11 R-HO-1 group ( group H2). For I/R experiments, ischemia was induced for 5 min by occluding the common carotid arteries bilater-ally with aneurysm clips under Ketamine anesthesia. The experiment was conducted after the neurons were intraperitoneally injected with 5mg·kg-1 saline,11R , 11R-HO-1,or 25mg · kg-1 11R-HO-1 for 3 h. The rats were killed after 24h of reperfusion. Hippocampus was removed immediately for determination of cAMP level, neuronal apoptotic rate, and expression of HO-1 and Caspase-3 protein, mitochondria was observed un-der electron microscope. Results Among group C, group S and group R,there were no differences in the expressions of HO-1, Caspase-3 protein, cAMP level , neuronal apoptotic rate and mitochondria damage ( P>0. 05). Compared with group C, group S and group R, the expression of HO-1 protein was up-regulated, the expression of Caspase-3 protein was down-regula-ted, cAMP level increased, the apoptotic rate was sig-nificantly decreased and mitochondria damage de-creased in group H1 ( P < 0. 01 ) . Compared with group H1 , the expression of HO-1 protein was up-regu-lated, the expression of Caspase-3 protein was down-regulated, cAMP level increased, the apoptotic rate was significantly decreased and mitochondria damage decreased in group H2 ( P <0. 01 ) . Conclusion Transducted-HO-1 protein can attenuate brain ischemi-a-reperfusion rat hippocampal neurons injury.

Expression and bioactivity of protein transduction domain-paraoxonase 1 fusion protein / 国际药学研究杂志

Objective Using silkworm expression system to express human serum paraoxonase 1 (PON1) fusion protein with protein transduction domain P11 and to study its biological activity of fighting aginst the toxicity of dichlorvos. Methods P11-PON1 fusion gene was constructed in cloning sites of silkworm pFastBac 5B vector, the vector and was transformed to silkworm DH10BmBac competent cells. Virus particles and 5 instar silkworm was infected 96 hours after infection, parasites were collected and lyophilized crushed and preserved at-80℃. The protien was dissolved, sonicated and centrifuged before used. Supernatants were harvested. The fusion protein P11-PON1 proportion of the total protein was analyzed with SDS-PAGE electrophoresis and protein content was calculated. Mouse and zebrafish models were used to evaluate P11-PON1 fusion protein bioactivity. Each mouse was treated with 1 mg P11-PON1 fusion protein via intragastric or rectal administration. 0 and 3 hours after administration, 20 mg/kg dichlorvos were injected intraperitoneally. The status of intoxication was observed and the survival rate was scored. P11-PON1 fusion protein with concentrations of 1, 2.5, 5, 10, 20 mg/L was dissolved in zebrafish breeding water respectively. 0 and 3 hours after exposing dichlorvos were added with a final concentration of 50 mg/L. Observe their behavioral change.The survival rate of zebrafish was recorded. Results The content of P11-PON1 fusion protein was 8%of silkworm total protein. In mice experiments, P11-PON1 fusion protein by intragastric adminstration did not increase the survival of mouse. By intraperitoneal injection with dichlorvos 0h after rectal adminstration with protein,the survival rate of mouse did not significantly increase. In contrast, the mouse intraperitoneally injected with dichlorvos 3h after adminstration with protein, the survival rate increased extremely significantly (P < 0.01). In zebrafish experiments, the zebrafish exposed to dichlorvos 0 h after adminstration with protein, the survival rate was not significantly improved, while exposed to dichlorvos 3h after admindtration, the survival rate significantly increased. The survival rate of 20, 10, 5 mg/L group were 62.5%, 62.5%and 50%respectively at 24 h time point, compared to the control group. The survival rate increased extremely significantly (P < 0.01). 2.5 mg/L group was 41.7%, with the survival rate increasing significantly (P < 0.05). However, the survival rate of 1 mg/L group was 16.7%, compared to the control group. The increase had no sistatistical significance. Conclusion The PTD-containing PON1 fusion protein can be expressed in silkworm. Pretreatment with the fusion protein in mice and zebrafish decreased the toxicity of dichlorvos.

Development and Application of Cell-penetrating Peptides

Intracellular transduction of hydrophilic macromolecules has been problematic owing to the biochemical restriction imposed by lipid bilayer of the cytoplasmic membrane. Several technologies have been developed to improve the intracellular delivery of the large molecules for therapeutic purpose, including cell penetrating peptide. Cell penetrating peptides or cell permeable peptides (CPPs) were initially discovered based on the potency of certain full-length proteins or proteins to translocate across the plasma membrane. Currently, CPPs are broadly applied for intracellular delivery of biologically functional molecules in vivo and vitro, varying from small molecules, peptides, proteins, liposomes and nucleic acids. With introducing the history and characteristics of CPPs, this review will focus on the intracellular transduction mechanism and application of CPPs.

Secretory TAT-peptide-mediated protein transduction of LIF receptor α-chain distal cytoplasmic motifs into human myeloid HL-60 cells

The distal cytoplasmic motifs of leukemia inhibitory factor receptor α-chain (LIFRα-CT3) can independently induce intracellular myeloid differentiation in acute myeloid leukemia (AML) cells by gene transfection; however, there are significant limitations in the potential clinical use of these motifs due to liposome-derived genetic modifications. To produce a potentially therapeutic LIFRα-CT3 with cell-permeable activity, we constructed a eukaryotic expression pcDNA3.0-TAT-CT3-cMyc plasmid with a signal peptide (ss) inserted into the N-terminal that codes for an ss-TAT-CT3-cMyc fusion protein. The stable transfection of Chinese hamster ovary (CHO) cells via this vector and subsequent selection by Geneticin resulted in cell lines that express and secrete TAT-CT3-cMyc. The spent medium of pcDNA3.0-TAT-CT3-cMyc-transfected CHO cells could be purified using a cMyc-epitope-tag agarose affinity chromatography column and could be detected via SDS-PAGE, with antibodies against cMyc-tag. The direct administration of TAT-CT3-cMyc to HL-60 cell culture media caused the enrichment of CT3-cMyc in the cytoplasm and nucleus within 30 min and led to a significant reduction of viable cells (P < 0.05) 8 h after exposure. The advantages of using this mammalian expression system include the ease of generating TAT fusion proteins that are adequately transcripted and the potential for a sustained production of such proteins in vitro for future AML therapy.

Inhibitory effect of PTD-OD-HA fusion protein on Bcr-Abl in K562 cells / 解放军医学杂志

Objective To study the transduction dynamics, location of PTD-OD-HA fusion protein and its interaction with Bcr-Abl oncoprotein in K562 cell lines, and explore the influence of PTD-OD-HA fusion protein on oligomerization and tyrosine kinase activity of Bcr-Abl. Methods PTD-OD-HA fusion protein was labeled with FITC and co-cultured with K562 cells. The transduction efficiency of labeled PTD-OD-HA at different doses and time intervals was observed under fluorescence microscope. The location of labeled PTD-OD-HA fusion protein in K562 cells was detected by confocal microscopy. The interaction of PTD-OD-HA fusion protein with Bcr-Abl oncoprotein was confirmed by coimmunoprecipitation. The phosphorylation of Bcr-Abl oncoprotein was detected by Western blotting. Results PTD-OD-HA fusion protein labeled with FITC was transduced into K562 cells in a dose- and time-dependent manner. PTD-OD-HA fusion protein was located in the cytoplasm of K562 cells and was consistent with the location of Bcr-Abl oncoprotein. The interaction of PTD-OD-HA fusion protein with Bcr-Abl oncoprotein was proved in K562 cells. This interaction could interrupt the homologous oligomerization of Bcr-Abl oncoprotein and reduce the phosphorylation of Bcr-Abl oncoprotein. Conclusion PTD-OD-HA fusion protein could be transduced into K562 cells efficiently, inhibit the oligomerization and reduce the phosphorylation of Bcr-Abl oncoprotein.

Inhibitory effect of PTD-OD-HA fusion protein on Bcr-Abl in K562 cells / 解放军医学杂志

Objective To study the transduction dynamics, location of PTD-OD-HA fusion protein and its interaction with Bcr-Abl oncoprotein in K562 cell lines, and explore the influence of PTD-OD-HA fusion protein on oligomerization and tyrosine kinase activity of Bcr-Abl. Methods PTD-OD-HA fusion protein was labeled with FITC and co-cultured with K562 cells. The transduction efficiency of labeled PTD-OD-HA at different doses and time intervals was observed under fluorescence microscope. The location of labeled PTD-OD-HA fusion protein in K562 cells was detected by confocal microscopy. The interaction of PTD-OD-HA fusion protein with Bcr-Abl oncoprotein was confirmed by coimmunoprecipitation. The phosphorylation of Bcr-Abl oncoprotein was detected by Western blotting. Results PTD-OD-HA fusion protein labeled with FITC was transduced into K562 cells in a dose- and time-dependent manner. PTD-OD-HA fusion protein was located in the cytoplasm of K562 cells and was consistent with the location of Bcr-Abl oncoprotein. The interaction of PTD-OD-HA fusion protein with Bcr-Abl oncoprotein was proved in K562 cells. This interaction could interrupt the homologous oligomerization of Bcr-Abl oncoprotein and reduce the phosphorylation of Bcr-Abl oncoprotein. Conclusion PTD-OD-HA fusion protein could be transduced into K562 cells efficiently, inhibit the oligomerization and reduce the phosphorylation of Bcr-Abl oncoprotein.

Protective effects of TAT-tCNTF fusion protein on SH-SY5Y cells induced by β-amyloid peptide(25-35) / 中国药理学通报

Aim To determine TAT-Tcntf penetration ability and to investigate the effects of the fusion protein on SH-SY5Y cells against toxicity induced by β-amyloid peptide 25-35(Aβ_(25-35) ).Methods The conjugate(TAT-tCNTF)of TAT(47-57)of HIV-1 and the truncated human CNTF active fragment was genetic engineered and expressed in E.Coli.Immunofluorescence was used to identify cell permeation ability across membrane.MTT assay was used to measure the survival of SH-SY5Y cells injured by Aβ_(25-35).And Hoechst 33342/PI double staining was used to observe the morphology of cell apoptosis and necrosis.LDH was measured by spectrophotometric method.Results The expression vector of pBV220-TAT-tCNTF was constructed successfully.Western blot showed the recombinant fusion protein could bind specifically with CNTF antibody.The immunofluorescence assay clearly demonstrated that TAT-tCNTF did penatrate into the cells while little rhCNTF pass across the cells.Double staining and LDH release assay demonstrated that TAT-tCNTF could promote significantly the survival of the cells.Conclusion sTAT-tCNTF with high activities and effective transmembrane ability is obtained for the first time.The fusion protein protects SH-SY5Y cells from death after Aβ25-35 exposure.

Recognition of protein transduction domain by support vector machine / 国际生物医学工程杂志

Objective To predict protein transduction domain (PTD) which is a short peptide with the ability to pull diverse molecules across cell membranes.Methods Every peptide segment including PTDs and peptide sequence from SwissProt database was represented by 68 numerical values,which reflected their physicochemical and conformational properties related to the PTD' s membrane penetrating function.Transductive support vector machine (TSVM) and support vector machine(SVM),combined with cluster method,was introduced to predict new PTDs from the peptide segments,which were extracted from SwissProt database.Results TSVM prediction model achieved 94%±4% accuracy and SVM model achieved 94%±5% accuracy.1210 possible PTDs were predicted using the classifiers based on these two models.Conclusion The research provides a guide to find more PTDs in molecular biology experiments and will be helpful in the understanding of the mechanism of PTDs and their function in vivo.

Effect of PTD-ΔPRD Foxp3 fusion protein on the mixed lymphocyte reaction in mice / 中南大学学报(医学版)

Objective To express protein transduction domain (PTD)-deletion proline domain (ΔPRD) Foxp3 fusion protein, and to analyze its influence on mixed lymphocyte reaction in mice.Methods We cloned mouse ΔPRD of Foxp3 gene by PCR, and inserted it into pET28a-PTD, pET28a-PTD-eGFP vector, then expressed fusion proteins in E.coli Rosetta (DE3). The fusion proteins were purified and refolded by Profinity IMAC Ni~(2+)-Charged Resin. The expression of fusion proteins was identified by Western blot. Flow cytometry assay was used to detect the effect of PTD-ΔPRD fusion protein to transduce into mouse EL-4 cells. The ability of fusion protein to inhibit the proliferation of EL-4 cells was analyzed by two-way mixed lymphocyte reaction.Results The PTD-ΔPRD fusion proteins were expressed and purified efficiently. Western blot and flow cytometry indicated that PTD-ΔPRD fusion protein was transduced into EL-4 efficiently. Mixed lympocyte reaction assay showed that PTD-ΔPRD fusion protein had the bioactivity to inhibit the proliferation of EL-4 cells.Conclusion The PTD-ΔPRD fusion protein was expressed in E.coli system and could be transduced into cells effectively, suggesting that PTD-ΔPRD fusion protein may be an inhibitor in lymphocytes from mouse spleen.

Bone regenerative effects of recombinant human bone morphogenetic protein-2 employed protein transduction domain / 대한치주과학회지

Bone morphogenetic proteins(BMPs) are regarded as members of the transforming growth factor-beta superfamily with characteristic features in their amino acid sequences. A number of studies have demonstrated the biologic activities of BMPs, which include the induction of cartilage and bone formation. Recently there was a attempt to overcome a limitation of mass production, and economical efficieny of rh-BMPs. The method producing PTD by using bacteria have advantages of acquiry a mass of proteins. Hences, a new treatment which deliver protein employed by protein transduction domain(PTD) has been tried. The purpose of this study was to evaluate the bone regenerative effect of TATBMP-2 and TAT-HA2-BMP-2 employed by PTD from HIV-1 TAT protein for protein translocation in the rat calvarial model. An 8mm calvarial, critical size osteotomy defect was created in each of 32 male Spraque-Dawley rats(weight 250~300g). The animals were divided into 4 groups of 32 animals each (4 animals/group/healing interval). The defect was treated with TATBMP-2/ACS(Absorbable collagen sponge) (TATBMP-2 0.1mg/ml), TAT-HA2-BMP-2/ACS(TAT-HA2-BMP-2 0.1mg/ml), ACS alone or left untreated for surgical control(negative control). The rats were sacrificed at 2 or 8 weeks postsurgery, and the results were evaluated histologically. The results were as follows: New bone formation were not significantly greater in the TATBMP-2/ACS group relative to negative, and positive control groups. New bone was evident at the defect sites in TAT-HA2-BMP-2/ACS group relative to negative, positive control and TATBMP-2 groups. There were a little bone regeneration in TATBMP-2 groups. While, enhanced local bone formation were observed in TAT-HA2-BMP-2 group. But, The results was not the same in all rat defects. Therefore, further investigations are required to develop a method, which disperse homogenously, and adhere to target cells.

Cell-penetrating peptide PEP-1 mediated transmembrane delivery of enhanced green fluorescent protein in vivo of mouse / 基础医学与临床

Objective To investigate the in vivo transduction capability of fusion protein PEP-1-EGFP with mice.Methods Two prokaryotic expression plasmids pET15b-EGFP and pET15b-PEP-1-EGFP were constructed and transformed into E.coli BL21(DE3) to express EGFP and fusion protein PEP-1-EGFP,respectively.The expressed EGFP and PEP-1-EGFP were purified with Ni2+-resin affinity chromatography.Five hundred micrograms of EGFP and PEP-1-EGFP fusion protein were injected into mouse through caudal vein,respectively,the mice were euthanized and perfused with PBS 2 hours after administration.Then,the heart,brain,liver,spleen and kidney were removed and sectioned with a cryostat at 7 ?m for visualization with a inverted fluorescent microscope.ResultsThe brain,heart,liver,spleen and kidney injected with PEP-1-EGFP showed bright and homogenous green fluorescence whereas that with EGFP showed no green fluorescence at all.Conclusion The successful expression and purification of PEP-1-EGFP fusion protein and its efficient transduction into mice in vivo provide a basis for the research on transmembrane delivery of macromolecule drugs mediated by the cell-penetrating peptide,PEP-1.

Application of protein transduction in gene therapy / 国际生物医学工程杂志

Protein transduction is an emerging technique in biological fields in recent years. Through the medium of protein transduction domain(PTD) composed by a small number of alkaline peptides, the functional proteins linked covalently with DNA, peptides, proteins or other macromolecules can across the membranes of mammalian cells, even the blood-brain barrier and transfer unconventionally that isn't like classical pathway. The distinct property of PTD that can take along fused protein entering into cells unconventionally offers a new vehicle to gene therapy for some diseases and has dulcet applied perspective.

Poliovirus-derived CTL-inducing Hepatitis C Vaccine by Modification of RPS-Vax with Protein Transduction Domain

We have reported RPS-Vax system by introducing multiple cloning site (MCS) and 3C-protease cutting site at the N-terminal end of the poliovirus Sabin 1 cDNA. Potential vaccine genes can be easily introduced into recombinant polioviral genome and expressed during the viral replication as a part of virus polyprotein and subsequently processed from the mature viral protein by the poliovirus-specific 3C-protease. However, these poliovirus vector-mediated chimeric viral vaccine was not efficient to induce the cell-mediated immunity because of its rapid cytolytic capacity. In order to make CTL-inducing vaccine vector, we integrated a protein transduction domain (PTD) into the pRPS-Vax vector system right ahead of the MCS, named RPS-Vax/PTD. We have incorporated the HCV core (N-terminal 100aa) antigen into the MCS of pRPSvax-PTD vector, followed by production of chimeric virus, named RPSvax-PTD/HCVc. The chimeric virus was genetically stable during the serial passages. Replication capacity of the RPSvax-PTD/HCVc was 1~2 log lower than that of RPS-Vax control virus. These chimeric virus was very efficient to inducing antigen-specific IgG2a in the immunized mice, implying that the recombinant virus has a capacity to induce HCV-specific Th1 type immunity in the immunized animals or humans.

Poliovirus-derived CTL-inducing Hepatitis C Vaccine by Modification of RPS-Vax with Protein Transduction Domain

We have reported RPS-Vax system by introducing multiple cloning site (MCS) and 3C-protease cutting site at the N-terminal end of the poliovirus Sabin 1 cDNA. Potential vaccine genes can be easily introduced into recombinant polioviral genome and expressed during the viral replication as a part of virus polyprotein and subsequently processed from the mature viral protein by the poliovirus-specific 3C-protease. However, these poliovirus vector-mediated chimeric viral vaccine was not efficient to induce the cell-mediated immunity because of its rapid cytolytic capacity. In order to make CTL-inducing vaccine vector, we integrated a protein transduction domain (PTD) into the pRPS-Vax vector system right ahead of the MCS, named RPS-Vax/PTD. We have incorporated the HCV core (N-terminal 100aa) antigen into the MCS of pRPSvax-PTD vector, followed by production of chimeric virus, named RPSvax-PTD/HCVc. The chimeric virus was genetically stable during the serial passages. Replication capacity of the RPSvax-PTD/HCVc was 1~2 log lower than that of RPS-Vax control virus. These chimeric virus was very efficient to inducing antigen-specific IgG2a in the immunized mice, implying that the recombinant virus has a capacity to induce HCV-specific Th1 type immunity in the immunized animals or humans.

Expression of TAT-Smad7-HA fusion protein and validation of its transduction activity / 第三军医大学学报

Objective To construct,express,purify,identify and label the TAT-Smad7-HA fusion protein (protein transduction domain of trans-activator,human Smad7 and hyaluronic acid) and to validate its transduction activity in the cultured human primary keloid fibroblast cells. Methods TAT-PTD,Smad7 and HA fragments were sequentially inserted into pET32a(+) to construct the pTAT-Smad7-HA prokaryotic expression vector. After the expression of target fusion protein was induced to express by IPTG,affinity purification,Western blot analysis,enterokinase cleavage,target protein capture and FITC labeling were subsequently performed by turns to obtain the FITC-TAT-Smad7-HA fusion protein and to further observe its transduction activity in the human primary KFB cells in vitro. Results The prokaryotic expression vector for the TAT-Smad7-HA fusion protein,named as pTAT-Smad7-HA was successfully constructed,and the target fusion protein was efficiently induced to express,covering more than 25% of the total bacterial proteins,successfully purified with a purity of more than 95% purity,desalted by desalting column,identified by Western blotting,thioredoxin removed and FITC labeled. Finally,a fusion protein of FITC-TAT-Smad7-HA with the approximately molecular weight of 50?103 was successfully purified and its high transduction activity in KFB cells was validated. Conclusion The highly-purified FITC-TAT-Smad7-HA fusion protein and the validation of its high transduction activity in KFB cells have provided an experimental foundation for further studies on the role the human Smad7 protein playing in the TGF-?/Smads signal transduction pathway and further elucidation of the pathogenesis of keloid formation.

Drug delivery to the brain using PTD transport systems / 中国药理学通报

Blood brain barrier is the main obstacle for drug delivery to the brain.To overcome the limited access of drugs to the brain,three methods have been developed at present:neurosurgical-based strategies,chemistry-based strategies to increase the lipid solubility of the drug,and biology-based strategies of endogenous BBB transporters-mediated drug delivery.PTD transport system to delivery drug across BBB is an emerging technology,which conveniently and efficiently deliver various molecules into spinal cord and brain via blood,intraperitoneally etc.PTD transport system offers a new approach to central nervous system disease with quick,convenient and safe charcteristics.

Construction,expression and purification of pTAT-HIF-1?-PAS-B in prokaryotic expression system / 第三军医大学学报

Objective To construct a prokaryotic expression vector for a fusion protein, TAT protein transduction domain (PTD) and the PAS-B domain of hypoxia inducible factor 1?(HIF-1?), and then express and purifr the fusion protein. Methods The expression plasmids pTAT-PAS-B, pET-PAS-B and pTAT-EGFP were constructed respectively, and transformed into E. coli. BL21(DE3)pLysS strain to be induced by IPTG. The obtained proteins were analyzed by SDS-PAGE and Western blotting. The fusion protein were purified with Ni-NTA-His affinity chromatography. Results The three recombinant plasmids were constructed successfully. The objective fusion proteins were obtained by optimizing the conditions for expression and purification. Conclusion The successful expression and purification of the fusion protein TAT-HIF-1?PAS-B has laid the foundation for using it to modulate the activity of HIF-1? in vivo.

Preparation of Protein Transduction Domain Modified Mice IFN-? / 中国药房

OBJECTIVE:To prepare PTD modified mice interferon gamma(PTD-mIFN-?) in order to prepare for its function research.METHODS:The code of PTD-mIFN-? fragment was amplified by PCR for 3 times,using pUC19/mIFN-? as template.The PCR product was cloned into pUC19 plasmid and then constructed into expression plasmid vector pQE80L after sequencing.After double digestion with BamH Ⅰ and Hind Ⅲ,the recombinant vector was identified in 1.2% agarose gel.The target protein and PTD-mIFN-? was checked by SDS-PAGE,Western blot method and ELISA assay,respectively.Recombinant protein was purified by nikel ion-triglycollamic acid(Ni2+-NTA) Agarose affinity chromatogram.RESULTS:The cDNA fragment encoding PTD-mIFN-? amplified by PCR was obtained.The high-level expression of recombinant protein was noted in SDS-PAGE and Western blot assay.The target protein was obtained by ELISA assay.CONCLUSION:PTD-mIFN-? was prepared successfully.