PURPOSE: Apoptosis of vascular endothelial cells is a type of endothelial damage that is associated with the pathogenesis of cardiovascular diseases such as atherosclerosis. Heterotrimeric GTP-binding proteins (G proteins), including the alpha 12 subunit of G protein (Galpha12), have been found to modulate cellular proliferation, differentiation, and apoptosis of numerous cell types. However, the role of Galpha12 in the regulation of apoptosis of vascular cells has not been elucidated. We investigated the role of Galpha12 in serum withdrawal-induced apoptosis of human umbilical vein endothelial cells (HUVECs) and its underlying mechanisms. MATERIALS AND METHODS: HUVECs were transfected with Galpha12 small-interfering RNA (siRNA) to knockdown the endogenous Galpha12 expression and were serum-deprived for 6 h to induce apoptosis. The apoptosis of HUVECs were assessed by Western blotting and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The expressions of microRNAs were analyzed by quantitative real-time PCR. RESULTS: Knockdown of Galpha12 with siRNA augmented the serum withdrawal-induced apoptosis of HUVECs and markedly repressed the expression of microRNA-155 (miR-155). Serum withdrawal-induced apoptosis of HUVECs was inhibited by the overexpression of miR-155 and increased significantly due to the inhibition of miR-155. Notably, the elevation of miR-155 expression prevented increased apoptosis of Galpha12-deficient HUVECs. CONCLUSION: From these results, we conclude that Galpha12 protects HUVECs from serum withdrawal-induced apoptosis by retaining miR-155 expression. This suggests that Galpha12 might play a protective role in vascular endothelial cells by regulating the expression of microRNAs.
*Apoptosis ; Atherosclerosis/*blood/genetics/immunology ; Cell Proliferation ; Endothelial Cells/*metabolism ; GTP-Binding Protein alpha Subunits, G12-G13/*genetics ; Gene Expression Profiling ; Gene Expression Regulation ; Human Umbilical Vein Endothelial Cells/cytology ; Humans ; MicroRNAs/*metabolism ; Protective Agents ; *RNA, Small Interfering ; Real-Time Polymerase Chain Reaction ; *Transfection

Acute graft-versus-host disease (aGVHD) is a serious complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the mechanisms of aGVHD are not well understood. We aim to investigate the roles of the three angiogenic factors: angiopoietin-1 (Ang-1), Ang-2 and vascular endothelial growth factor (VEGF) in the development of aGVHD. Twenty-one patients who underwent allo-HSCT were included in our study. The dynamic changes of Ang-1, Ang-2 and VEGF were monitored in patients before and after allo-HSCT. In vitro, endothelial cells (ECs) were treated with TNF-β in the presence or absence of Ang-1, and then the Ang-2 level in the cell culture medium and the tubule formation by ECs were evaluated. After allo-HSCT, Ang-1, Ang-2 and VEGF all exhibited significant variation, suggesting these factors might be involved in the endothelial damage in transplantation. Patients with aGVHD had lower Ang-1 level at day 7 but higher Ang-2 level at day 21 than those without aGVHD, implying that Ang-1 may play a protective role in early phase yet Ang-2 is a promotion factor to aGVHD. In vitro, TNF-β promoted the release of Ang-2 by ECs and impaired tubule formation of ECs, which were both weakened by Ang-1, suggesting that Ang-1 may play a protective role in aGVHD by influencing the secretion of Ang-2, consistent with our in vivo tests. It is concluded that monitoring changes of these factors following allo-HSCT might help to identify patients at a high risk for aGVHD.
Acute Disease ; Adolescent ; Adult ; Angiogenesis Inducing Agents ; immunology ; metabolism ; pharmacology ; Angiopoietin-1 ; genetics ; immunology ; pharmacology ; Angiopoietin-2 ; genetics ; immunology ; pharmacology ; Antineoplastic Agents ; therapeutic use ; Female ; Gene Expression Regulation, Neoplastic ; Graft vs Host Disease ; genetics ; immunology ; pathology ; Hematopoietic Stem Cell Transplantation ; Human Umbilical Vein Endothelial Cells ; cytology ; drug effects ; immunology ; Humans ; Leukemia, Myeloid ; genetics ; immunology ; pathology ; therapy ; Lymphoma, Non-Hodgkin ; genetics ; immunology ; pathology ; therapy ; Male ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; immunology ; pathology ; therapy ; Retrospective Studies ; Signal Transduction ; Transplantation, Homologous ; Tumor Necrosis Factor-alpha ; pharmacology ; Vascular Endothelial Growth Factor A ; genetics ; immunology

OBJECTIVETo explore the role of CD44 in monocyte adhesion to human brain microvascular endothelial cells (HBMECs) and monocyte migration across an in vitro model of blood-brain barrier (BBB) infected by Cryptococcus neoformans (Cn).

METHODSAn in vitro blood-brain barrier model was constructed using a transwell chamber covered with a HBMEC monolayer. The wild-type strain of Cn B4500FO2, TYCC645#32 strain with CPS1 gene deletion and PCIP strain with CPS1 complementation were chosen to infect the monolayer HBMECs. THP-1 cells were added to the upper chamber of transwell, and the relative migration rate was determined by counting the number of the cells entering the lower chambers. The inhibitory effects of anti-CD44 monoclonal antibody and the CD44 inhibitor bikunin were examined on THP-1 binding to and migration across HBMECs.

RESULTSCn infection of the HBMECs caused markedly enhanced THP-1 cell adhesion and migration across the monolyers (P<0.01) dependent on Cn concentration and exposure time. Addition of anti-CD44 monoclonal antibody and bikunin significantly lowered THP-1 adhesion and migration rates in the BBB model with Cn-infected HBMECs (P<0.01) with a dose dependence of the antibody (within 0-1 µg) and inhibitor (within 0-20 nmol/L). Both THP-1 adhesion rate and migration rate were lowered in the BBB model infected with CPS1 gene-deleted Cn but increased in the model infected with the complemented strain compared with those in the wild-type strain-infected model.

CONCLUSIONIn the in vitro BBB model, CD44 expressed on HBMECs may play an essential role in monocyte adhesion to and migration across the BBB. The capsular hyaluronic acid may mediate Cn-induced monocyte adhesion and migration.

Blood-Brain Barrier ; immunology ; microbiology ; Brain ; cytology ; microbiology ; Cell Line ; Cryptococcosis ; immunology ; Cryptococcus neoformans ; Endothelial Cells ; microbiology ; Humans ; Hyaluronan Receptors ; metabolism ; Monocytes ; cytology

BACKGROUNDCell transplantation has great potential for promoting endothelial repair and reducing the complications of percutaneous coronary intervention (PCI). The aim of this study was to investigate the effect of transplantation of human umbilical cord blood endothelial progenitor cells (EPCs) on injured arteries.

METHODSUmbilical cord blood mononuclear cells were obtained from post-partum lying-in women, and EPCs were isolated, cultured, expanded and identified by immunofluorescence. The carotid arterial endothelium of New Zealand white rabbits was injured by dilatation with a 3F balloon, and the EPCs were injected into the lumen of the injured artery in the transplanted group (n = 16), while an equal volume of phosphated buffered saline (PBS) was injected into the control group after balloon injury (n = 16). The animals were sacrificed after either 2 or 4 weeks, and the grafted cells were identified by double immunofluorescence staining with human nuclear antigen (HNA) and CD31 antibodies. Arterial cross sections were analyzed by pathology, immunohistochemistry and morphometry to evaluate the reparative effects of EPCs. Proliferating cell nuclear antigen (PCNA) and transforming growth factor (TGF)-β1 mRNA expression were detected by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSFluorescence-labeled EPCs were found in the neointima. The neointimal area and the neointimal/medial area ratio were significantly lower in the transplanted group than in the control group (P < 0.05). von Willebrand factor (vWF) immunohistostaining showed more VWF-positive cells in the transplanted animals than in the controls (8.75 ± 2.92 vs. 4.50 ± 1.77, P < 0.05). Compared with the control group, the transplanted group had lower expression of PCNA mRNA (0.67 ± 0.11 vs. 1.25 ± 0.40, P < 0.01) and higher expression of TGF-β1 mRNA (1.10 ± 0.21 vs. 0.82 ± 0.07, P < 0.05).

CONCLUSIONSEPCs derived from human umbilical cord blood were successfully transplanted into injured vessels. The transplanted EPCs inhibited neointimal hyperplasia and promoted vascular re-endothelialization.

Animals ; Carotid Artery Injuries ; immunology ; pathology ; therapy ; Cell Differentiation ; Cells, Cultured ; Cytokines ; genetics ; Endothelial Cells ; cytology ; physiology ; Fetal Blood ; cytology ; Humans ; Hyperplasia ; Male ; Neointima ; pathology ; Proliferating Cell Nuclear Antigen ; genetics ; RNA, Messenger ; analysis ; Rabbits ; Stem Cell Transplantation ; Transforming Growth Factor beta1 ; genetics

OBJECTIVETo observe the effect of apoptosis of human umbilical vein endothelial cells (HUVEC) induced by IgA1 from Henoch-Schönlein purpura (HSP) patients.

METHODHUVEC were cultured in 3 different conditional media with IgA1 from HSP patients, normal healthy children and simply the cell culture medium. Serum IgA1 was purified by jacalin affinity chromatography, rates of apoptosis in HUVEC cells at different concentration and different times after incubation with IgA1 were determined by TUNEL method and flow cytometry. Real-time PCR and Western blot methods were used to detect the expression of caspase-3 and Fas, respectively.

RESULTApoptosis rate of HUVEC by IgA1 isolated from HSP patients were significantly higher than that of the blank control [(14.77 ± 2.23)% vs. (2.25 ± 0.77)%, P < 0.01] and the apoptosis rate of HUVEC induced by IgA1 from normal healthy children was higher than that of blank control [(7.97 ± 1.48)% vs. (2.25 ± 0.77)%, P < 0.01]. The apoptosis rate of HUVEC induced by IgA1 from HSP was time and concentration-dependent. Moreover IgA1 isolated from HSP patients could significantly increase the caspase-3 and Fas expression (P < 0.01).

CONCLUSIONThe IgA1 from HSP patients could induce the apoptosis of HUVEC, which might be related to the progression of HSP.

Adolescent ; Apoptosis ; drug effects ; Caspase 3 ; genetics ; metabolism ; Cells, Cultured ; Child ; Child, Preschool ; Dose-Response Relationship, Drug ; Fas Ligand Protein ; genetics ; metabolism ; Female ; Flow Cytometry ; Gene Expression Regulation ; drug effects ; Human Umbilical Vein Endothelial Cells ; cytology ; drug effects ; metabolism ; Humans ; Immunoglobulin A ; blood ; isolation & purification ; pharmacology ; In Situ Nick-End Labeling ; Male ; Purpura, Schoenlein-Henoch ; blood ; immunology ; RNA, Messenger ; metabolism ; Real-Time Polymerase Chain Reaction ; Time Factors

This study was aimed to investigate the expression of GST-CML28 in Escherichia Coli and to prepare its antibody. The constructed recombinant expression vectors CML28-pGEX-3X were transformed into Escherichia Coli BL21 under IPTG induction. The protein was abstracted from the transformers, and purified by a GSTrap FF column. The rabbits were immunized by the purified fusion protein to produce serum with anti-CML28 antibody. The serum was purified by chromatographic column stuffed with glutathione Sephamse 4B to get the antibody. The specific antibody against CML28 was further identified by ELISA, Western blot, immunohistochemistry and quantum dot luminescence. The results indicated that GST-CML28 fusion protein was expressed in Escherichia coli and its specific polyclonal antibody was obtained. It is concluded that the anti-CML28 polyclonal antibodies with high titer and specificity are successfully prepared. These antibodies provide an useful experimental tool to profoundly research the physiological significance and biological function of the CML28 gene.
Animals ; Antibodies ; immunology ; isolation & purification ; metabolism ; Antigens, Neoplasm ; biosynthesis ; immunology ; isolation & purification ; Cells, Cultured ; Escherichia coli ; metabolism ; Exosome Multienzyme Ribonuclease Complex ; biosynthesis ; immunology ; isolation & purification ; Genetic Vectors ; Glutathione Transferase ; biosynthesis ; isolation & purification ; Human Umbilical Vein Endothelial Cells ; cytology ; Humans ; RNA-Binding Proteins ; biosynthesis ; immunology ; isolation & purification ; Rabbits ; Recombinant Fusion Proteins ; biosynthesis ; immunology ; isolation & purification

OBJECTIVETo assess the prevalence of anti-alpha-enolase antibody in systemic autoimmune diseases in Chinese patients and its role in endothelial cell apoptosis.

METHODSThe reactivity of anti-alpha-enolase antibody in a variety of autoimmune disorders in Chinese patients was evaluated by dot blot assay. Endothelial cell apoptosis was investigated by in vitro incubation of endothelial cells with IgG purified from anti-alpha-enolase antibody-positive sera, with or without pre-incubation with recombinant alpha-enolase.

RESULTSAnti-alpha-enolase antibody was prevalent in different systemic autoimmune diseases with relatively high reactivity in Chinese patients. In vitro incubation of endothelial cells with IgG containing anti-alpha-enolase antibody induced apoptosis in a time- and dose-dependent manner. Apoptosis was partly inhibited by pre-incubation of the endothelial cells with recombinant alpha-enolase.

CONCLUSIONSOur data suggest that alpha-enolase is a common auto-antigen recognized by anti-endothelial cell antibodies in connective tissue disease. Interaction between alpha-enolase and its autoantibody plays a role in endothelial cell apoptosis. Changes other than cell killing may contribute to the pathogenesis of endothelial damage and microvascular lesions.

Adolescent ; Adult ; Apoptosis ; drug effects ; Autoantibodies ; immunology ; pharmacology ; Autoimmune Diseases ; immunology ; Blotting, Western ; Cell Line ; Endothelial Cells ; cytology ; drug effects ; Female ; Flow Cytometry ; Humans ; Immunoblotting ; Male ; Middle Aged ; Phosphopyruvate Hydratase ; immunology ; metabolism ; Young Adult

BACKGROUNDOverwhelming evidences on chronic myeloid leukemia (CML) indicate that patients harbor quiescent CML stem cells that are responsible for blast crisis. While the hematopoietic stem cell (HSC) origin of CML was first suggested over 30 years ago, recently CML-initiating cells beyond HSCs are also being investigated.

METHODSWe have previously isolated fetal liver kinase-1-positive (Flk1(+)) cells carrying the BCR/ABL fusion gene from the bone marrow of Ph(+) patients with hemangioblast property. In this study, we isolated CML patient-derived Flk1(+)CD31(-)CD34(-) mesenchymal stem cells (MSCs) and detected their biological characteristics and immunological regulation using fluorescence in situ hybridization (FISH) analysis, fluorescence activated cell sorting (FACS), enzyme-linked immunoadsorbent assay, mixed lymphocyte reaction assays; then we compared these characters with those of the healthy donors.

RESULTSCML patient-derived Flk1(+)CD31(-)CD34(-) MSCs had normal morphology, phenotype and karyotype while appeared impaired in immuno-modulatory function. The capacity of patient Flk1(+)CD31(-)CD34(-) MSCs to inhibit T lymphocyte activation and proliferation was impaired in vitro.

CONCLUSIONSCML patient-derived MSCs have impaired immuno-modulatory functions, suggesting that the dysregulation of hematopoiesis and immune response may originate from MSCs rather than hematopoietic stem cells (HSCs). MSCs might be a potential target for developing efficacious treatment for CML.

Adolescent ; Adult ; Antigens, CD34 ; genetics ; metabolism ; Apoptosis ; drug effects ; Blotting, Western ; Cell Cycle ; drug effects ; Cells, Cultured ; Enzyme-Linked Immunosorbent Assay ; Female ; Flow Cytometry ; Fusion Proteins, bcr-abl ; genetics ; metabolism ; Humans ; Immunomodulation ; In Situ Hybridization, Fluorescence ; Karyotype ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; enzymology ; immunology ; metabolism ; Male ; Matrix Metalloproteinase 9 ; genetics ; metabolism ; Mesenchymal Stromal Cells ; cytology ; immunology ; Middle Aged ; Platelet Endothelial Cell Adhesion Molecule-1 ; genetics ; metabolism ; T-Lymphocytes ; Vascular Endothelial Growth Factor Receptor-2 ; genetics ; metabolism ; Young Adult

Gene transfer of basic fibroblast growth factor (bFGF) has been shown to induce significant endothelial migration and angiogenesis in ischemic disease models. Here, we investigate what factors are secreted from skeletal muscle cells (SkMCs) transfected with bFGF gene and whether they participate in endothelial cell migration. We constructed replication-defective adenovirus vectors containing the human bFGF gene (Ad/bFGF) or a control LacZ gene (Ad/LacZ) and obtained conditioned media, bFGF-CM and LacZ-CM, from SkMCs infected by Ad/bFGF or Ad/LacZ, respectively. Cell migration significantly increased in HUVECs incubated with bFGF-CM compared to cells incubated with LacZ-CM. Interestingly, HUVEC migration in response to bFGF-CM was only partially blocked by the addition of bFGF-neutralizing antibody, suggesting that bFGF-CM contains other factors that stimulate endothelial cell migration. Several proteins, matrix metalloproteinase-1 (MMP-1), plasminogen activator inhibitor-1 (PAI-1), and cathepsin L, increased in bFGF-CM compared to LacZ-CM; based on 1-dimensional gel electrophoresis and mass spectrometry. Their increased mRNA and protein levels were confirmed by RT-PCR and immunoblot analysis. The recombinant human bFGF protein induced MMP-1, PAI-1, and cathepsin L expression in SkMCs. Endothelial cell migration was reduced in groups treated with bFGF-CM containing neutralizing antibodies against MMP-1 or PAI-1. In particular, HUVECs treated with bFGF-CM containing cell-impermeable cathepsin L inhibitor showed the most significant decrease in cell migration. Cathepsin L protein directly promotes endothelial cell migration through the JNK pathway. These results indicate that cathepsin L released from SkMCs transfected with the bFGF gene can promote endothelial cell migration.
Antibodies, Neutralizing/immunology ; Cathepsin L/genetics/*metabolism ; *Cell Movement ; Cells, Cultured ; Comet Assay ; Dependovirus/genetics ; Endothelial Cells/cytology/*metabolism ; Fibroblast Growth Factor 2/genetics/immunology/*metabolism ; Gene Transfer Techniques ; Humans ; Immunoblotting ; JNK Mitogen-Activated Protein Kinases ; Lac Operon/genetics ; Mass Spectrometry ; Matrix Metalloproteinase 1/biosynthesis/genetics ; Muscle, Skeletal/*metabolism ; Neovascularization, Physiologic ; Plasminogen Activator Inhibitor 1/biosynthesis/genetics ; RNA, Messenger/biosynthesis ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo investigate the prevalence of anti-endothelial cell antibodies (AECAs) in the sera of connective tissue diseases (CTD) patients with pulmonary arterial hypertension (PAH) and its correlation with clinical manifestations.

METHODSAECAs in sera of 39 CTD patients with PAH, 22 CTD patients without PAH, and 10 healthy donors as controls were detected with Western blotting. The prevalence of different AECAs in different groups was compared and its correlation with clinical manifestations was also investigated.

RESULTSThe prevalence of AECAs was 82.1% in CTD patients with PAH, 72.7% in CTD patients without PAH, and 20.0% in healthy donors. Anti-22 kD AECA was only detected in CTD patients with PAH (15.4%). Anti-75 kD AECA was more frequently detected in CTD patients with PAH than in those without PAH (51.3% vs. 22.7%, P < 0.05). In CTD patients with PAH, anti-75 kD AECA was more frequently detected in those with Raynaud's phenomenon or with positive anti-RNP antibody.

CONCLUSIONAECAs could be frequently detected in CTD patients with or without PAH, while anti-22 kD and anti-75 kD AECA might be specific in CTD patients with PAH.

Adult ; Autoantibodies ; blood ; immunology ; Cell Line ; Connective Tissue Diseases ; blood ; immunology ; pathology ; physiopathology ; Endothelial Cells ; cytology ; immunology ; Female ; Humans ; Hypertension, Pulmonary ; blood ; immunology ; pathology ; physiopathology ; Middle Aged