DC-SIGN targets amphotericin B-loaded liposomes to diverse pathogenic fungi.

BACKGROUND: Life-threatening invasive fungal infections are treated with antifungal drugs such as Amphotericin B (AmB) loaded liposomes. Our goal herein was to show that targeting liposomal AmB to fungal cells with the C-type lectin pathogen recognition receptor DC-SIGN improves antifungal activity. DC-SIGN binds variously crosslinked mannose-rich and fucosylated glycans and lipomannans that are expressed by helminth, protist, fungal, bacterial and viral pathogens including three of the most life-threatening fungi, Aspergillus fumigatus, Candida albicans and Cryptococcus neoformans. Ligand recognition by human DC-SIGN is provided by a carbohydrate recognition domain (CRD) linked to the membrane transit and signaling sequences. Different combinations of the eight neck repeats (NR1 to NR8) expressed in different protein isoforms may alter the orientation of the CRD to enhance its binding to different glycans. RESULTS: We prepared two recombinant isoforms combining the CRD with NR1 and NR2 in isoform DCS12 and with NR7 and NR8 in isoform DCS78 and coupled them to a lipid carrier. These constructs were inserted into the membrane of pegylated AmB loaded liposomes AmB-LLs to produce DCS12-AmB-LLs and DCS78-AmB-LLs. Relative to AmB-LLs and Bovine Serum Albumin coated BSA-AmB-LLs, DCS12-AmB-LLs and DCS78-AmB-LLs bound more efficiently to the exopolysaccharide matrices produced by A. fumigatus, C. albicans and C. neoformans in vitro, with DCS12-AmB-LLs performing better than DCS78-AmB-LLs. DCS12-AmB-LLs inhibited and/or killed all three species in vitro significantly better than AmB-LLs or BSA-AmB-LLs. In mouse models of invasive candidiasis and pulmonary aspergillosis, one low dose of DCS12-AmB-LLs significantly reduced the fungal burden in the kidneys and lungs, respectively, several-fold relative to AmB-LLs. CONCLUSIONS: DC-SIGN's CRD specifically targeted antifungal liposomes to three highly evolutionarily diverse pathogenic fungi and enhanced the antifungal efficacy of liposomal AmB both in vitro and in vivo. Targeting significantly reduced the effective dose of antifungal drug, which may reduce drug toxicity, be effective in overcoming dose dependent drug resistance, and more effectively kill persister cells. In addition to fungi, DC-SIGN targeting of liposomal packaged anti-infectives have the potential to alter treatment paradigms for a wide variety of pathogens from different kingdoms including protozoans, helminths, bacteria, and viruses which express its cognate ligands.

Modified Panax ginseng Extract Inhibits uPAR-Mediated α[Formula: see text]ß1-Integrin Signaling by Modulating Caveolin-1 to Induce Early Apoptosis in Lung Cancer Cells.

Urokinase receptor (uPAR) is enhanced in many human cancer cells and is frequently an indicator of poor prognosis. Activation of [Formula: see text]1-integrin requires caveolin-1 and is regulated by uPAR. However, the underlying molecular mechanism responsible for the interaction between uPAR and [Formula: see text]1-integrin remains obscure. We found that modified regular Panax ginseng extract (MRGX) had a negative modulating effect on the uPAR/[Formula: see text]1-integrin interaction, disrupted the uPAR/integrin interaction by modulating caveoline-1, and caused early apoptosis in cancer cells. Additionally, we found that siRNA-mediated caveoline-1 downregulation inhibited uPAR-mediated [Formula: see text]1-integrin signaling, whereas caveoline-1 up-regulation stimulated the signaling, which suppressed p53 expression, thereby indicating negative crosstalk exists between the integrin [Formula: see text]1 and the p53 pathways. Thus, these findings identify a novel mechanism whereby the inhibition of [Formula: see text]1 integrin and the activation of p53 modulate the expression of the anti-apoptotic proteins that are crucially involved in inducing apoptosis in A549 lung cancer cells. Furthermore, MRGX causes changes in the expressions of members of the Bcl-2 family (Bax and Bcl-2) in a pro-apoptotic manner. In addition, MGRX-mediated inhibition of [Formula: see text]1 integrin attenuates ERK phosphorylation (p-ERK), which up-regulates caspase-8 and Bax. Therefore, ERK may affect mitochondria through a negative regulation of caspase-8 and Bax. Taken together, these findings reveal that MRGX is involved in uPAR-[Formula: see text]1-integrin signaling by modulating caveolin-1 signaling to induce early apoptosis in A549 lung-cancer cells and strongly indicate that MRGX might be useful as a herbal medicine and may lead to the development of new herbal medicine that would suppress the growth of lung-cancer cells.

Placental villous mesenchymal cells trigger trophoblast invasion.

The successful transformation of uterine spiral arteries by invasion trophoblasts is critical for the formation of the human hemochorial placenta. Placental trophoblast migration and invasion are well regulated by various autocrine/paracrine factors at maternal-fetal interface. Human placental multipotent mesenchymal stromal cells (hPMSCs) are a subpopulation of villous mesenchymal cells and have been shown to produce a wide array of soluble cytokines and growth factors including HGF (hepatocyte growth factor). The function of hPMSCs in placental villous microenvironment has not been explored. The interaction between hPMSCs and trophoblasts was proposed in vitro in a recent article. HGF produced by hPMSCs was able to engage c-Met receptor on trophoblast and induced the trophoblast cAMP expression. The cAMP activated PKA, which in turn, signaled to Rap1 and led to integrin ?1 activation. The total integrin ?1 protein expression by trophoblasts was not affected by HGF stimulation. Hypoxia downregulated HGF expression by hPMSCs. HGF and PKA activator 6-Bnz-cAMP increased trophoblast adhesion and migration that were inhibited by PKA inhibitor H89 or Rap1 siRNA. Thus, hPMSCs-derived paracrine HGF can regulate trophoblast migration during placentation. These findings provided insight revealing at least one mechanism by which hPMSCs implicated in the development of preeclampsia.

No Synergistic Effect of Combined Olmesartan and Temocapril on Reversal of Left Ventricular Hypertrophy / 中华高血压杂志

Objective To explore whether combined olmesartan angiotensin Ⅱ receptor type 1 blocker(ARB) and angiotensin-converting enzyme inhibitor(ACEI) temocapril have synergistic effect on reversal of left ventricular hypertrophy (LVH) in stroke-prone spontaneously hypertensive rats (SHRsp). Methods Fourty-four SHRsps and 11 Wistar-Kyoto rats(WKY) were divided randomly into 5 groups:WKY-control group, SHRsp-control group, SHRsp-olmesartan 10 mg/(kg?d)group, SHRsp-temocapril 10 mg/(kg?d)group, and SHRsp-Olmesartan 3 mg/(kg?d)+temocapril 3 mg/(kg?d) group for 6 weeks. Hearts weight were measured and histologically studied. The mRNA expression of angiotensin Ⅱ receptor type 1(AT1R) and integrin ?1 in myocardium was detected by RT-PCR. Results Olmesartan, temocapril and the their combination significantly reduced systolic blood pressure in a similar magnitude. Combination therapy was shown not greater effect in reversal of LVH than by olmesartan alone, although the effect by both of them was greater than temocapril monotherapy. The mRNA levels of AT1R and integrin ?1 in SHRsp were significantly decreased by treatment with olmesartan, temocapril, or combination therapy. Olmesartan and combination therapy result in greater decreases in expression of AT1R and integrin ?1 mRNA in myocardium than that by temocapril. Conclusion Compared with olmesartan alone, the combination of ARS and ACEI didn't show synergistic effect on reversal of left ventricular hypertrophy as were down-regulation of AT1R and suppression of integrin ?1 mRNA in myocardium.

The Effect of Cytokine on Myocardial Fibrosis of Chronic Viral Myocarditis and the Interventional Treatment of QingXinⅡ / 浙江中医药大学学报

[Objective]To study the effect of TGF?1 on the expression of fibronectin and ?1 integrin receptor in chronic viral myocarditis of myocardial fibrosis induced by repeated virus infection and the interventional effect of QingXin.[Methods] Establish mice model of myocardial fibrosis in chronic stage of viralmyocarditis,then divide the mice model into model group,captopril group,QingXinⅡ high dose,medium dose and low dose groups.The normal group and model group are given saline through stomach perfusing,as well as the treated group are given respectively captopril and QingXinⅡ high,medium and low dose in the same way.After the treatment,hearts are collected,CVB3-RNA are detected by RT-PCR,TGF?1 and FN are detected by immunohistochemical technique,integrin?1 are analyzed by immunofluorescence staining-confocal laser scanning.[Results] After having done the model,TGF?1,integrin?1,FN has increased obviously;virus can be detected in themyocardium by RT-PCR;after the intervention of QingXinⅡ,TGF?1,integrin?1,FN has decreased,virus has reduced in treated group.[Conclusion] Virus,TGF?1,integrin?1 and FN have important effects on the formation ofmyocardial fibrosis;QingXinⅡ has the function of antivirus and anti-myocardial fibrosis.

Preliminary analysis of side population phenotypes in human epithelial cells / 中国现代普通外科进展

Objective:To explore side population(SP) cells in human epithelial cells and to observe the expression of the universal stem cell marker ABCG2,epidermal stem cell markers ?6 integrin and ?1 integrin on SP cells.Methods:Epithelial cells were obtained by digesting human skins with Dispase II and Trypsin and stained with Hoechst33342 and PI.The SP cells were analyzed and sorted by the fluorescence-activated cell sorter.Then the expression of ABCG2,?6 integrin and ?1 integrin was analyzed by flow cytometry.Results:SP cells accounted for 0.2%-0.3% of total human epithelial cells.Only a small part of cells expressed ABCG2,integrin ?6 and integrin ?1 of both SP cells and total human epithelial cells detected by flow cytometry.The difference of positive rates between SP cells and total human epithelial cells was not significant.Conclusion:SP cells accounted for 0.2%-0.3% of total human epithelial cells.The difference of positive rates of stem cells marker ABCG2,integrin ?6 and integrin ?1 between SP cells and total human epithelial cells was not significant.

A mechanism study of the inhibition of the adhesion of human gastric cancer MKN1 cells and suppression of the expression of integrin ?_1 gene by dextran sulfate / 中国药理学通报

Aim To observe the adhesive process of the human gastric cancer cell line MKN1,and study the expression of integrin ?1;to investigate the mechanism of the inhibition of the adhesion process of MKN1 cells by destran sulfate(DS).Methods The MKN1 cells were cultured with DS or PBS,then stained with immunofluorescent cytochemistry and observed in fixed or living conditions with confocal laser scanning microscope.RT-PCR was used to analyze the cDNA expression of MKN1 cells.Results MKN1 cells adhered to culture dishes by the process of forming filopodia,changed into a flat shape,and then adhered to other cells to form a cell-monolayer.Integrin ?1 was intensively expressed in the cell membrane,where integrin ?1 formed clusters.DS inhibted the expression of integrin ?1 in cell membrane,and decreased the area of integrin ?1 clusters.DS-treated cells also tended to maintain a round shape by contracting the filopodia.In DS-containing culture dishes,some cells kept floating 4 hours after seeding.DS decreased the level of the cDNA expression of the adhered cells to 74% and of the floating cells to 38% of that of the cells in un-treated group,respectively.Conclusion The inhibition of the adhesion of MKN1 cells by DS was related to the suppression of the expression of integrin ?1.

The expression of integrin ?_(1) and its prognostic significance in osteosarcoma / 第三军医大学学报

Objective To investigate the expression of integrin ?_(1) in human osteosarcoma_()and its relationship to prognosis.Methods The expression of integrin ?_(1)was measured by immunohistochemistry and its relationship to prognosis was analyzed statistically.Results Twenty-five of 34 osteosarcoma specimens were found positive staining of integrin ?_(1)(73.5%).The expression levels of integrin ?_(1)was not related to Dahlin classification of osteosarcoma,age and sex,but significantly increased in the osteoblast type and was related to poor survival.Conclusion Integrin ?_(1) can serve as a new biological indicator for the prognosis in osteosarcoma.

Expression of Integrin ?_1 in Human Hepatocellular Carcinoma / 中国医师杂志

Objective To study the expression of integrin ?1 in hepatocellular carcinoma (HCC) and its significance. Methods Integrin ?1 expression was detected in 38 cases of HCC, 8 cases of hepatic cirrhosis (HC) and 7 cases of normal liver tissues(NL) using immunohistochemical SP method. The relationship between the integrin ?1 expression and HCC clinico-pathological features was analyzed. Results The positive rate of integrin ?1 expression in the HCC was much higher than that in the HC and NL tissues (P

Effect of 1-deoxynojirimycin on high glucose-stimulating proliferation of rat mesangial cells / 中华内分泌代谢杂志

The effect of 1-deoxynojirimycin(DNJ)on the proliferation of rat mesangial cells was observed and its mechanism was explored.The results showed that DNJ significantly inhibited the proliferation of rat mesangial cells induced by high glucose in time-and dose-dependent manners.DNJ significantly decreased expressions of?-smooth muscle action(?-SMA),integrin?1 mRNA and protein and focal adhesion kinase (FAK)protein stimulated by high glucose in rat mesangial cells(P

Effect of rosiglitazone on the expression of integrin ?_1 in lung adenocarcinoma A549 cells / 中国药理学通报

Aim To investigate the molecular mechanism of Rosiglitazone on the expression of integrin ?1 in lung pulmonary carcinoma A549 cell line. Methods RT-PCR and flow cytometry methods were used to examine the expression of mRNA and cell total protein of PPAR? and integrin ?1 subunit. Results The expression of PPAR? mRNA and integrin ?1 mRNA had dose-dependent regulating action by Rosiglitazone,using PPAR? inhibitor GW9662 and ERK pathway inhibitor PD98059 could abolish the inhibition of PPAR? on the expression of integrin ?1. Conclusion The effect of PPAR? ligand Rosiglitazone on integrin ?1 expression is mediated through PPAR?-dependent signaling parthway. The mechanism may be partly involved in ERK pathway.

INTEGRIN ?1 MAY PLAY IMPORTANT ROLE IN HUMAN EGG FERTILIZATION AND EARLY EMBRYO DEVELOPMENT:A CONFOCAL MICROSCOPY STUDY / 解剖学报

Objective To investigate distribution of integrain ?1 in human oocytes and embryos before and after maturation/fertilization,dring the first and second meiosis,in morulae and blastocyst stage. Methods Human oocytes and embryos were stained by anti-integrin ?1 (PharMingen 09351D) and FITC-labeled second antibody (PharMingen 110094D),and observed by confocal microscope. Results Integrin ?1 concentrated in the nuclear area in matured oocytes,zygotes and 2-cell stage embryo,indicating that integrin ?1 might involve in mitosis.Dislike mouse,there was no distribution of integrin ?1 on the well-accepted sperm binding area on the oocytes,indicating that integrin ?1 might not involve in the binding and fusion of human sperm to human oocytes.Conclusion It was first postulated that integrin ?1 might actively involve in the pronuclear fusion process in human in vitro fertilized oocytes.The marker of ectotrophoblasts,polarized distribution of integrin ?1, appeared at the morulae stage.The stronger expression in ectotrophoblasts around the inner cell mass might indicate some specific function of the ectotrophoblasts near the ICM.