Nonvolatile and Nonflammable Sulfolane-Based Electrolyte Achieving Effective and Safe Operation of the Li-O2 Battery in Open O2 Environment.

The Li-O2 battery should operate effectively/safely in an open O2 environment for practical applications, but not trapped in sealed/closed atmosphere. However, the typical use of volatile and flammable electrolyte restricts Li-O2 battery to be able to be running in open O2 environment. We report herein, for the first time, a highly electrochemical reversible Li-O2 battery operated in an open O2 environment, i.e., under the condition of keeping O2 flowing continuously based on a nonvolatile and nonflammable sulfolane (TMS) solvent. The electrochemical irreversibility of Li2O2/O2 conversion and incompatibility between Li metal anodes and electrolyte have been addressed via dissolving LiNO3 in concentrated TMS electrolyte. The tuned electrolyte not only enables a stable solid electrolyte interphase (SEI) with conformal inorganic components (including LiF, LiNxOy, and Li2O) that promotes a uniform Li electro-plating/stripping process but also results in a low charge overpotential, a stable discharge terminal plateau, and reversible O2 generation of the Li-O2 battery conducted in an open O2 environment.

Tim-3 and PD-1 regulate CD8+ T cell function to maintain early pregnancy in mice.

During pregnancy, CD8+ T cells are important regulators in the balance of fetal tolerance and antiviral immunity. T-cell immunoglobulin mucin-3 (Tim-3) and programmed cell death-1 (PD-1) are well-recognized negative co-stimulatory molecules involved in viral persistence and tumor metastasis. Here, we demonstrate that CD8+ T cells co-expressing Tim-3 and PD-1 were down-regulated in the deciduae of female mice in abortion-prone matings compared with normal pregnant mice. In addition to their reduced numbers, the Tim-3+PD-1+CD8+ T cells produced lower levels of the anti-inflammatory cytokines interleukin (IL)-4 and IL-10, as well as a higher level of the pro-inflammatory cytokine interferon (IFN)-γ, relative to those from normal pregnancy. Furthermore, normal pregnant CBA/J females challenged with Tim-3- and/or PD-1-blocking antibodies were more susceptible to fetal resorption. These findings indicate that Tim-3 and PD-1 pathways play critical roles in regulating CD8+ T cell function and maintaining normal pregnancy.

Embryonic trophoblasts induce decidual regulatory T cell differentiation and maternal-fetal tolerance through thymic stromal lymphopoietin instructing dendritic cells.

Physiological pregnancy requires the maternal immune system to recognize and tolerate embryonic Ags. Although multiple mechanisms have been proposed, it is not yet clear how the fetus evades the maternal immune system. In this article, we demonstrate that trophoblast-derived thymic stromal lymphopoietin (TSLP) instructs decidual CD11c(+) dendritic cells (dDCs)with increased costimulatory molecules; MHC class II; and Th2/3-type, but not Th1-type, cytokines. TSLP-activated dDCs induce proliferation and differentiation of decidual CD4(+)CD25(-) T cells into CD4(+)CD25(+)FOXP3(+) regulatory T cells (Tregs) through TGF-ß1. TSLP-activated dDC-induced Tregs display immunosuppressive features and express Th2-type cytokines. In addition, decidual CD4(+)CD25(+)FOXP3(+) Tregs promote invasiveness and HLA-G expression of trophoblasts, resulting in preferential production of Th2 cytokines and reduced cytotoxicity in decidual CD56(bright)CD16(-) NK cells. Of interest, decreased TSLP expression and reduced numbers of Tregs were observed at the maternal-fetal interface during miscarriage. Our study identifies a novel feedback loop between embryo-derived trophoblasts and maternal decidual leukocytes, which induces a tolerogenic immune response to ensure a successful pregnancy.

[Effects of Rapamycin and Rapamycin-loaded Poly(lactic-co-glycolic)Acid Nanoparticles on Apoptosis and Expression of bcl-2 and p27(kip1) Proteins of Human Umbilical Arterial Vascular Smooth Muscle Cell].

OBJECTIVE: To investgate the effects of rapamycin(RPM)and RPM-loaded poly(lactic-co-glycolic)acid(PLGA)nanoparticles(NPs)on the apoptosis of human umbilical arterial vascular smooth muscle cells(HUASMCs)in vitro and expression of bcl-2 and p27(kip1) protein. METHODS: HUASMCs were cultured in vitro and divided to RPM and RPM-PLGA-NPs groups treated at 3 different concentration by 12 and 24 hours,with M231-smooth muscle growth supplements medium and null-PLGA-NPs treated groups as controlled. The apoptosis of HUASMCs was determined by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling staining and flow cytometry. The expressions of bcl-2 and p27(kip1) were detected by streptacidin/peroxidase immunohistochemical method. The effect on cellular proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromidecolorimetry. RESULTS: The proliferation of HUASMCs was inhibited by RPM and RPM-PLGA-NPs in a dose-dependent manner. DNA electrophoresis showed DNA ladder in RPM and RPM-PLGA-NPs groups and classical scalar strips in control groups. The apoptotic indexes of RPM 100 ng/ml group and RPM-PLGA-NPs 500 ng/ml group detected by flow cytometry were(45.45<2.36)% and(35.04<5.64)%,respectively,which were significantly higher than that of M231-smooth muscle growth supplements control group [(2.60<0.95)%,all P<0.01]. The apoptotic indexes of groups incubated with RPM and RPM-PLGA-NPs for 24 hours were significantly higher than those of groups which incubated for 12 hours(P<0.05,P<0.01). The positive expression indexes(PEI)of p27(kip1) and bcl-2 protein were higher in RPM and RPM-PLGA-NPs groups than that of control groups. The Spearman's rank correlation coefficient test showed that there was no significant correlation between the PEI of p27(kip1) and the apoptotic indexes in the RPM group and RPM-PLGA-NPs group(P>0.05). CONCLUSIONS: Rapamycin-loaded PLGA nanoparticles and rapamycin have similar effects in inhibiting proliferation and inducing apoptosis;meanwhile,they upregulate the expression of p27(kip1) protein without downregulating the expression of bcl-2 protein in HUASMCs in vitro. RPM-PLGA-NPs has more potent pro-apoptotic effect than equivalent dose of RPM but is not linearly correlated with the p27(kip1) expression level.

Chemokine CCL28 induces apoptosis of decidual stromal cells via binding CCR3/CCR10 in human spontaneous abortion.

Spontaneous abortion is the most common complication of pregnancy. Immune activation and the subsequent inflammation-induced tissue injury are often observed at the maternal-fetal interface as the final pathological assault in recurrent spontaneous abortion. However, the precise mechanisms responsible for spontaneous abortion involving inflammation are not fully understood. Chemokine CCL28 and its receptors CCR3 and CCR10 are important regulators in inflammatory process. Here, we examined the expression of CCL28 and its receptors in decidual stromal cells (DSCs) by immunochemistry and flow cytometry (FCM), and compared their expression level in DSCs from normal pregnancy versus spontaneous abortion, and their relationship to inflammatory cytokines production by DSCs. We further analyzed regulation of the pro-inflammatory cytokines on CCL28 expression in DSCs by real-time polymerase chain reaction, In-cell Western and FCM. The effects of CCL28-CCR3/CCR10 interaction on DSC apoptosis was investigated by Annexin V staining and FCM analysis or DAPI staining and nuclear morphology. Higher levels of the inflammatory cytokines interleukin (IL)-1ß, IL-17A and tumor necrosis factor-α, and increased CCR3/CCR10 expression were observed in DSCs from spontaneous abortion compared with normal pregnancy. Treatment with inflammatory cytokines differently affected CCL28 and CCR3/CCR10 expression in DSCs. Human recombinant CCL28 promoted DSC apoptosis, which was eliminated by pretreatment with neutralizing antibodies against CCR3/CCR10 and CCL28. However, CCL28 did not affect DSC growth. These results suggest that the inflammation-promoted up-regulation of CCL28 and its receptors interaction in DSCs is involved in human spontaneous abortion via inducing DSC apoptosis.

Anti-DNA antibody modified coronary stent for plasmid gene delivery: results obtained from a porcine coronary stent model.

BACKGROUND: Previous work in our laboratory has demonstrated that the anti-DNA antibody-immobilized stent results in highly site-specific gene delivery in a rabbit carotid model. As a result of the similarity in the anatomy and physiology of the pig and human cardiovascular systems, the porcine coronary stent model was used in the present study to evaluate the site-specificity, efficiency and long-term therapeutic effect of this gene delivery system in pig coronary arteries. METHODS: A reporter plasmid pEGFP (pEGFP-C1) was tethered on the antibody-immobilized stents and assessed for site-specificity and efficiency in a pig coronary stent model. Inducible nitric oxide synthase (NOS) cDNA (pcDNA3.1-iNOS) was tethered on the stent as a therapeutic gene to evaluate the site-specificity and long-term therapeutic effect of this novel gene delivery system for the inhibition of restenosis after coronary stenting for 28 days. RESULTS: Both the pEGFP-C1 and pcDNA3.1-iNOS tethered stents achieved site-specific gene transfection without distal spreading in the porcine coronary model. The overall GFP transfection efficiency was 2.6 ± 0.9% of the total cells, whereas the neointimal transfection was more than 6%. Histology and morphology studies showed no significant artery stenosis and intimal proliferation for 28 days after coronary stenting using pcDNA3.1-iNOS tethered stents. CONCLUSIONS: For the first time, we report the successful use of anti-DNA antibody-immobilized stent as plasmid gene delivery system that possess high efficiency and site-specificity in a porcine coronary stent model. The novel system showed long-term therapeutic effects on the inhibition of restenosis when pcDNA3.1-iNOS was tethered on the stent.

[Study of three-dimensional fluorescence spectra for measuring chlorobenzene in water].

Quantitative analysis of chlorobenzene (CB) in water by three-dimensional fluorescence spectrometry was discussed in the present paper. The study showed that there is only one fluorescence peak for CB which lies in the range of excitation wavelength (lambdaex) 210-240 nm and emission wavelength (lambdaem) 330-370 nm. When measuring CB solution of concentration 0.002-0.05 mg x L(-1), the fluorescence intensity was the strongest as lamdaex/lamdaem was 225/340 nm, which presented linear correlation with concentration, and the related coefficient was 0.99967. The study proved that three-dimensional fluorescence spectrometry can be adopted for quantitative analysis of CB in water. With this method, the detection limit was 3.68 X 10(-6) mg x L(-1) and the standard deviation was 0.04% at 90% confidence level.

[Effects of rapamycin-loaded poly(lactic-co-glycolic) acid nanoparticles on distribution of cell cycle, expression of p27 protein, and proliferation of human umbilical arterial vascular smooth muscle cell in vitro].

OBJECTIVE: To evaluate the effects of rapamycin (RPM)-loaded poly (lactic-co- glycolic) acid (PLGA) nanoparticles (NPs) on the proliferation, distribution of cell cycle, and expression of p27 protein in human umbilical arterial vascular smooth muscle cell (HUASMC) in vitro. METHODS: The primarily culture model of HUASMC was successfully established by explant-attached method in vitro. The cells were administrated with different doses of RPM, and RPM-PLGA NPs were observed as treat groups compared with PLGA NPs and M231-SMGs medium cultured group. The effect of RPM-PLGA NPs on proliferation of HUASMC was assessed using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) colorimetry method. The influences of RPM-PLGA NPs on the cell cycle and cellular growth kinetics of HUASMCs were tested by flow cytometry. The effect of RPM-PLGA NPs on the expression of p27 protein of HUASMCs was assessed through an immunohistochemical method. RESULTS: Compared with the control group, the proliferation of HUASMCs was inhibited by 50 microg/L and higher concentration of RPM-PLGA NPs in a dose-dependent manner (P < 0.05). The numbers of cells entering cell cycle of S/G2/M phases were significantly lower in RPM-PLGA NPs and RPM treated groups. Histologically, the expression of p27 were up-regulated in 500 microg/L RPM-PLGA NPs and 100 microg/L RPM treated group (all P < 0.01 ) when compared with the control group. CONCLUSIONS: RPM-PLGA NPs has a similar effects as RPM in inhibiting the growth of in vitro cultured HUASMC. It can remarkably suppress the expression of in vitro cultured HUASMC p27 protein, arrest its cell cycle at G1/S phase, and inhibit its proliferation.

[Preparation of a biodegradable drug-eluting stent in myocardium channel].

OBJECTIVE: To prepare a biodegradable drug-eluting stent in myocardium channel and evaluate its effect on myocardium channel after transmyocardial revascularization (TMR). METHODS: A biodegradable drug-eluting stent was prepared using poly (epsilon-caprolactone) (PCL), bovine serum albumin (BSA), and poly (D, L-lactide-co-glycolide) (PLGA) as material of stent, model protein drug, and drug carrier respectively. The amount of BSA in stent and in vitro released BSA of stent were determined by the Coomassie brilliant blue assay. The mechanical strength of stent was tested by universal material testing machines. The material and structure of stent was characterized by nuclear magnetic resonance spectroscopy. The effect of stent on myocardium channel after TMR was evaluated in vivo by a standard animal model of chronic myocardial ischemia in miniswine. RESULTS: The stent could carry 13.1 microg BSA per mg of stent and the stent could release about 95% of BSA after 30 days. The stent diminished 80% of initial scale under the stress of 1.7 Mpa. It also kept the myocardium channel patency after TMR. CONCLUSIONS: A biodegradable drug-eluting stent in myocardium channel was successfully prepared. It can sustain the pressure from the heart and achieve the controlled release of drug. The stent can ensure the myocardium channel patency after TMR.

[Rapamycin-loaded poly (lactic-co-glycolic) acid nanoparticles for intraarterial local drug delivery: preparation, characterization, and in vitro/in vivo release].

OBJECTIVE: To sought to engineer and characterize a biodegradable nanoparticles (NPs) containing rapamycin which use poly (lactic-co-glycolic) acid (PLGA) as the carrier matrix and to assess its in vivo release characteristics by local drug delivery system intravascularly. METHODS: Rapamycin-loaded PLGA NPs were prepared by an emulsification/solvent evaporation technique, and NPs size distribution was assessed by submicro laser defractometer. The particle morphology was observed by scanning electron microscopy. In vitro release from the NPs was performed in TE buffer at 37 degrees C under rotation utilizing double-chamber diffusion cells on a shake stander. In vivo NPs intravascular local delivery were performed by DISPATCH catheter in New Zealand rabbit abdominal aorta and Chinese experimental mini-pigs coronary artery models. RESULTS: Biodegradable rapamycin loaded PLGA NPs were constructed successfully by emulsification solvent-evaporation technique. The diameter of rapamycin-PLGA NPs was around 246.8 nm with very narrow size distribution, and rapamycin-NPs showed good spherical shape with smooth uniform surface. Rapamycin loaded in NPs were around was 19.42%. Encapsulation efficiency of drug was over 77.53%. The in vitro release of rapamycin from NPs showed that 75% of the drug was sustained released over 2 weeks and controlled release in a linear pattern. After a single 10 minutes infusion of rapamycin-PLGA NPs suspension (5 mg/ml) under 20.27 kPa through DISPATCH catherter in vivo, the mean rapamycin levels at 7 day and 14 day were (2.438 +/- 0.439) and (0.529 +/- 0.144) microg/mg of the dry-weight of the artery segments (2 cm) which local delivery were administrated. CONCLUSIONS: PLGA NPs controlled drug delivery system for intraarterial local anti-proliferative drug delivery can potentially improve local drug concentration and prolong drug residence time in animal model in vivo. It should be appropriate for further study of its therapy efficiency in human.

[Surface-modified paclitaxel-loaded nanoparticles as local delivery system for the prevention of vessel restenosis].

The novel paclitaxel-loaded nanopaticle through surface modification with didodecylmethylammonium bromide (DMAB) was prepared and its prevenative against neointimal formation in a rabbit carotid artery injury model was tested. Paclitaxel-loaded nanoparticles were prepared from oil-water emulsions using biodegradable poly (lactic acid-co-glycolic acid) (PLGA). Specific additive for surface conjugation was added after particle formation. To enhance arterial retention using a cationic surfactant, DMAB, was used. The size and distribution, surface morphology and surface charge of the paclitaxel-loaded nanoparticles were then investigated by laser light scattering, scanning electron microscope and zeta potential analyzer. The drug encapsulation efficiency (EE) and in vitro release profile were measured by high-performance liquid chromatography (HPLC). Balloon injured rabbit carotid arteries were treated with single infusion of the paclitaxel-loaded NP suspension and observed for 28 days. The inhibitory effects of vascular smooth muscle cell migration and proliferation were evaluated as end-point. The NPs showed spherical shape with diameter ranging from 200 to 500 nm. The negatively charged PLGA NPs shifted to positive after the DMAB modification. The in vitro drug release profile showed a triphasic release pattern. 28 days later, morphologic analysis revealed that the inhibitory effect of intima proliferation is dose-dependent, and the 30 mg x mL(-1) nanoparticle concentration suspension could completely inhibit proliferation of intima. Paclitaxel-loaded nanoparticles through surface modification with DMAB provide an effective means of inhibiting proliferation response to vascular injury in the rabbit.

Co-Signaling Molecules in Maternal-Fetal Immunity.

Physiologically, a successful pregnancy requires the maternal immune system to recognize and tolerate the semiallogeneic fetus, and allow for normal invasion of trophoblasts. Thus, pregnancy complications are considered to be associated with dysfunctional maternal-fetal crosstalk. Co-signaling molecules are a group of cell surface molecules that positively or negatively modulate the immune response. Well studied in the fields of oncology and transplantation, they are also suggested to be involved in maternal-fetal crosstalk. Here, we review the latest knowledge on the expression and function of such co-signaling molecules, highlighting their immunoregulatory roles in maternal-fetal tolerance and decidual vascular remodeling, and their involvement in pathological pregnancies. This review may instruct future basic research on, and clinical applications for, maternal-fetal immunity.

Tim-3 inhibits low-density lipoprotein-induced atherogenic responses in human umbilical vein endothelial cells.

Endothelial injury and dysfunction followed by endothelial activation and inflammatory cell recruitment are factors contributing to the initiation and progression of atherosclerosis. Oxidized low-density lipoprotein (ox-LDL) promotes inflammation during atherogenesis and lipid deposition in the arterial wall. We observed that stimulation of human umbilical vein endothelial cells (HUVECs) with ox-LDL activated pro-inflammatory cytokine production and apoptosis, inhibited cell migration, and upregulated T-cell immunoglobulin and mucin domain 3 (Tim-3) expression. Tim-3, in turn, protected HUVECs from ox-LDL-induced apoptosis via the JNK pathway and reversed the inhibition of migration. Tim-3 also inhibited ox-LDL-induced inflammatory cytokine production by suppressing NF-κB activation. In addition, Tim-3 increased production of type 2 T helper cells (Th2) and regulatory T cell (Treg)-associated cytokines. Blocking Tim-3 reversed its effects on the inflammatory response to ox-LDL. Thus, Tim-3 signaling may be a "self-control" mechanism in ox-LDL-triggered inflammation in HUVECs. These results identify Tim-3 as a factor in HUVEC activity and suggest its potential in the treatment of atherosclerosis.

[Animal study of intravascular gene therapy based on polyurethane implantable devices].

OBJECTIVE: To explore the feasibility of utilizing two implantable devices made from modified polyurethane films with antibody tethered replication-defective adenoviruses encoding for green fluorescent protein (AdGFP) as gene delivery platforms. METHODS: Intra-aortic button implants of collagen-coated polyurethane films with antibody tethered AdGFP were sutured into the infrarenal aorta of adult pigs and pulmonary valve leaflet in juvenile sheep was replaced by polyurethane pulmonary valve cusp replacement with antibody-tethered AdGFP. After seven days, the buttons, prosthetic leaflets, and their surrounding tissues were explanted and evaluated for biocompatibility and AdGFP-mediated gene transfer by fluorescent microscopy and PCR analysis. RESULTS: In vivo analysis of gene transfer from collagen-coated polyurethane films in pig infrarenal aorta implants, one week explants of the collagen-coated polyurethane films demonstrated (14.2 +/- 2.5)% of neointimal cells on the surface of the implant. In sheep pulmonary valve leaflet replacement studies, polyurethane films with antibody tethered AdGFP vector demonstrated (25.1 +/- 5.7)% of cells attached to polyurethane valve leaflets were transduced in one week. PCR analyses showed that GFP DNA was not detectable in blood or distal tissues. CONCLUSION: Site-specific intravascular delivery of adenoviral vectors for gene therapy can be achieved with these two kinds of polyurethane implants utilizing the antivector antibody tethering mechanism.

[Application of monoclonal antibody immobilized polyurethane film for site-specific gene therapy].

OBJECTIVE: To study the feasibility of delivering viral gene vector from a collagen-coated polyurethane (PU) film through a mechanism involving monoclonal antiviral antibody tethering. METHODS: Anti-adenoviral monoclonal antibodies were covalently bound to the collagen-coated PU surface. These antibodies enabled tethering of replication defective adenoviruses through highly specific antigen-antibody affinity. The PU film-based gene delivery using antibody-tethered adenovirus encoding green fluorescent protein (GEP) was tested in rat arterial smooth muscle cell (A10 cell) culture in vitro. The virus binding stability was studied by incubating the collagen-coated PU film in PBS solution at 37 degrees C for 20 days, followed with A10 cell cultures with the incubated films and the corresponding buffer solution. RESULTS: PU films with antibody-tethered adenovirus encoding GFP demonstrated efficient and highly localized gene delivery to A10 cells. Virus binding was stable for at least 10 days at physiological conditions, more than 77% of the originally bound virus remained in the film after 15 day's incubation. CONCLUSION: Gene delivery using PU film-based anti-viral antibody tethering of vectors exhibited potentials of applications in a wide array of single or multiple therapeutic gene strategies, and in further stent-based gene delivery therapeutic strategies.

[Effect of gene transfer using nanoparticles as gene vector in different animal models].

OBJECTIVE: To evaluate the effect of antisense monocyte chemotactic protein-1 (A-MCP-1) nanoparticles (NPs) as gene carrier on gene transfer in two kinds of animal models. METHODS: Poly (lactic acid-co-glycolic acid) (PLGA) was used to make the NPs loaded with A-MCP-1 through a double-emulsion/solvent evaporation technique. NPs size was assessed by dynamic laser defractometer. The particle morphology was observed by scanning electron microscopy. DNA content in the NPs was measured by dissolving known amounts of NPs in chloroform and extracting DNA with water. In vitro release was performed in tris-EDTA buffer at 37 degrees C using double-chamber diffusion cells. The receiver buffer was replaced daily. The A-MCP-1 NPs was transfected into the cultured smooth muscle cells. PCR was used to evaluate the transfection of A-MCP-1. Cationic lipid (Lipofectamine) was used to transfect A-MCP-1 as control. After 48 hours incubation, cells were digested and examined by polymerase chain reaction. Twenty New Zealand white rabbits under jugular vein to artery bypass grafting procedure were divided into four groups: the first group received grafts treated with A-MCP-1 NPs, the second group received grafts treated with cationic liposome (dioleoyl trimethyl ammonium propane)-A-MCP-1, the third group received grafts treated with plasmid DNA, and the fourth group received grafts without transfection as control. Fourteen days after surgery the grafts were harvested. The expression of A-MCP-1 and its effect on MCP-1 in vein grafts were detected by dot blotting. The morphology of the grafts was investigated. To establish abdominal aortic aneurysms rats model, rats were randomly divided into three groups: A-MCP-1 NPs injection group, shame NPs injection group and control groups (without injection). Two weeks after surgery, diameter of abdominal aorta was measured and aortic tissue was obtained for PCR analysis to evaluate the A-MCP-1 expression. Western blot were applied to detect the inhibitory effect to the expression of MCP-1 mRNA and CD68 protein by A-MCP-1 NPs. RESULTS: NPs size ranged 198nm to 205nm with average around 201.4 nm. DNA content in the NPs was 4.14%. NPs showed steady release rate in vitro in Tris-EDTA solution. It released faster in the first week then maintained a slowly sustained release up to 16 days. In cell culture A-MCP-1 gene successfully transfected into smooth muscle cells by NPs vector. In vein grafting animal model, A-MCP-1 expression was detected in the vascular walls of NPs and cationic lipid treated groups. The degree of vascular hyperplasia in the gene NPs treated group was significantly lower than that in control group. There was no significant difference in the inhibition of intimal hyperplasia between NPs and cationic lipid treated groups. Two weeks after transfection in abdominal aortic aneurysm rats models, the abdominal aortic diameter of A-MCP-1 NPs injection group was (1.79 +/- 0.12) mm, significantly smaller than that of control groups [shame NPs group was (2.58 +/- 0.21) mm, and saline group was (2.63 +/- 0.29) mm] (P < 0.01). The expressions of MCP-1 mRNA and CD68 protein in A-MCP-1 NPs injection group were 12.5 +/- 1.5 and 17.6 +/- 2.1, which were much lower than those in control group [in shame NPs group, which were 35.7 +/- 4.5, 42.3 +/- 5.7 (P < 0.01), and saline group which is 32.4 +/- 3.9, 39.8 +/- 4.8 (P < 0.01)]. Specific band of A-MCP-1 was detected only in the A-MCP-1 NPs injection group by PCR. CONCLUSION: A-MCP-1 gene NPs can be successfully used in rabbit vein grafting model and abdominal aortic aneurysm rats models, and may be potentially applied in clinical practice.

[A novel anti-DNA antibody modified coronary stent for site-specific plasmid DNA delivery].

OBJECTIVE: To explore the feasibility of using an endovascular metal stent as a highly efficient and site-specific gene delivery system. METHODS: Stents were formulated with a collagen coating. Anti-DNA monoclonal antibodies were covalently bound to the collagen surface by a cross linking reagent of N-succinimidyl 3-(2-pyridyldithio) propionate (SPDP). Binding capacity and stability of antibody and plasmid DNA on stents were quantified by radioactive labeling. The gene transduction efficiency was evaluated in cell culture and in rabbits. RESULTS: The amount of antibodies binding on collagen matrix through SPDP reaction was 15 times higher than that of through physical absorption (P < 0.005). The binding stability of plasmid was significantly better than the control groups (P < 0.01). There was no harmful effect on cell growth with the anti-DNA antibody modified stents. The stents retrieved from cell culture after 72 hours of incubation in A10 cells showed numerous transducted cells only infiltrating the surface coating indicating a highly localized and efficient gene delivery pattern. Results of in vivo gene transfer by this modified stent revealed (2.8 +/- 0.7)% of total cells transduction and the higher transduction location was neointimal layer (about 7%). No distal spread of vector was detectable in the anti-DNA antibody modified stent implantation animals. CONCLUSIONS: Anti-DNA antibody modified stents represent a novel highly efficient and site-specific gene delivery system which can deliver various kinds of plasmid vectors. The release of plasmid DNA tethered on the stents could be controlled in some conditions. This novel system provided a novel platform for cardiovascular site-specific gene therapy.

[Research progresses on electroactive and electrically conductive polymers for tissue engineering scaffolds].

Electroactive and/or electrically conductive polymers have shown potential applications in the culture of excitable cells and as the electroactive scaffolds for neuronal or cardiac tissue engineering. The biocompatibility of the conductive polymer can be improved by covalently grafting or blending with oligo- or polypeptides. The new progresses in this area on two types of conductive polymers, polypyrrole and polyaniline (PANi) are reviewed in this paper. The studies of oligopeptide-modified PANi and electrospun PANi/gelatin nanofibers are highlighted.

The Galectin-9/Tim-3 pathway is involved in the regulation of NK cell function at the maternal-fetal interface in early pregnancy.

Decidual natural killer (dNK) cells actively participate in the establishment and maintenance of maternal-fetal immune tolerance and act as local guardians against infection. However, how dNK cells maintain the immune balance between tolerance and anti-infection immune responses during pregnancy remains unknown. Here, we demonstrated that the inhibitory molecule T-cell immunoglobulin domain and mucin domain-containing molecule-3 (Tim-3) are expressed on over 60% of dNK cells. Tim-3(+) dNK cells display higher interleukin (IL)-4 and lower tumor necrosis factor (TNF)-α and perforin production. Human trophoblast cells can induce the transformation of peripheral NK cells into a dNK-like phenotype via the secretion of galectin-9 (Gal-9) and the interaction between Gal-9 and Tim-3. In addition, trophoblasts inhibit lipopolysaccharide (LPS)-induced pro-inflammatory cytokine and perforin production by dNK cells, which can be attenuated by Tim-3 neutralizing antibodies. Interestingly, a decreased percentage of Tim-3-expressing dNK cells were observed in human miscarriages and murine abortion-prone models. Moreover, T helper (Th)2-type cytokines were decreased and Th1-type cytokines were increased in Tim-3(+) but not Tim-3(-) dNK cells from human and mouse miscarriages. Therefore, our results suggest that the Gal-9/Tim-3 signal is important for the regulation of dNK cell function, which is beneficial for the maintenance of a normal pregnancy.

[Influence of water-soluble additives on drug release kinetics from biodegradable poly(lactic-co-glycolic acid) matrix].

AIM: To evaluate the effects of an array of additives on drug release from double-layered poly(lactic-co-glycolic acid) (PLGA) matrices. METHODS: Additives differing in molecular size, hydrophilicity and steric configuration were selected for this study. An anti-proliferative 2-aminochromone, U-86983 (U-86, Pharmacia and Upjohn), was used as a model agent because of our interest in investigating local drug delivery systems for the inhibition of restenosis. RESULTS: In vitro release of U-86 PLGA matrices without additive showed a typical biphasic release kinetics, i.e. a slow diffusion release (Phase I) followed by a fast erosion-mediated release (Phase II). The water-soluble additives in PLGA matrices changed the biphasic release pattern to a near monophasic profile by increasing the release of the Phase I. Increasing the ratio of additives to PLGA in matrices caused a significant increase in U-86 release rates. A high molecular weight water-soluble additive, Pluronic F127, resulted in a matrix showing perfect zero-order release kinetics. The morphologic evaluation of matrices using scanning electron microscopy indicated that the water-soluble additives were leachable and thus generated a highly porous structure in the matrices. Conclusion Water-solubility, molecular size and steric configuration of additives are the important determinants in generating various types of pore structures in polymer matrix which in turn affect the release mechanism and release kinetics.