Expressions of Tissue Factor and Tissue Factor Pathway Inhibitor in Patients with Acute Graft-versus-host Disease after Allogeneic Hematopoietic Stem Cell Transplantation

This study examined the expressions of human serum tissue factor （TF） and tissue factor pathway inhibitor （TFPI） in patients with acute graft-versus-host disease （aGVHD） after allogeneic hematopoietic stem cell transplantation （allo-HSCT） and their clinical significance. The serum TF and TFPI levels were detected by ELISA in 28 allo-HSCT recipients before and after the transplanta-tion and the changes of TF and TFPI levels were dynamically monitored at different phases of the disease. No significant differences in the serum TF and TFPI levels were found in allo-HSCT recipi-ents in the absence of aGVHD or with gradeⅠaGVHD before and after the transplantation. The lev-els of serum TF and TFPI were substantially increased in the patients with gradeⅡ aGVHD at the peak of aGVHD （P〈0.05） and they were even higher in the patients with grade Ⅲ–Ⅳ aGVHD （P〈0.01）. When the conditions became stable after treatment with immunosuppressive agents, the serum TFPI level was decreased to the baseline level （P〉0.05） and the TF level was lowered but still higher than the baseline level （P〈0.05）. It was concluded that the levels of serum TF and TFPI were increased significantly in the patients with grade Ⅱ–Ⅳ aGVHD after allo-HSCT and decreased markedly after the treatment. Monitoring the levels of serum TF and TFPI in the patients with allo-HSCT is important to predict the occurrence, outcome and prognosis of aGVHD.

Homocysteine-induced Enhanced Expression of Tissue Factor in Human Vascular Smooth Muscle Cells

The homocysteine （Hcy）-induced tissue factor （TF） expression in human vascular smooth muscle cells （VSMCs） and the effect of Hcy on the activity of nuclear factor-kappaB （NF-кB） and the expression of inducible nitric oxide synthase （iNOS） were investigated. Human umbilical artery VSMCs were cultured by tissue explanting method, identified by α-actin immunohistochemistry, and incubated with different concentrations of Hcy/PTDC （NF-кB inhibitor）. Semi-quantitative RT-PCR was performed to detect the expression of TF mRNA in VSMCs. Flow cytometry was used to assay the expression of TF protein on the surface of VSMCs and the expression of iNOS in VSMCs. Western blot was carried out to detect the expression of NF-кB protein in nuclei. The results showed that Hcy could induce VSMCs expressing TF mRNA significantly after the VSMCs were incubated with Hcy at concentrations of 10, 100, 500 μmol/L respectively. There was low expression level of TF protein on the surface of the resting VSMCs and Hcy could also induce VSMCs expressing TF pro- tein on the cell surface in different concentrations. Additionally, Hcy could rapidly induce the activation of NF-кB and this effect could be significantly inhibited by PDTC. Hcy alone could not induce the expression of iNOS in VSMCs. It was concluded that Hcy could significantly induce the expression of TF in VSMCs and enhance the activation of NF-ΚB, subsequently mediate TF gene expression and protein synthesis. NF-кB-mediated expression of TF in VSMCs might be the important mechanism of atherosclerosis and thrombosis induced by Hcy.

Binding of EGF1 Domain Peptide in Coagulation Factor Ⅶ with Tissue Factor and Its Implications for the Triggering of Coagulation

The binding function of EGF1 domain peptide with tissue factor(TF)and its ability of triggering coagulation were explored.The TF expression model in vitro was established by lipopolysaccha-ride induction.The affinity of EGFP-EGF1 and TF expressing cells was analyzed by fluorescence microscopy and flow cytometry(FCM).The affinity of EGFP-EGF1 and rat soluble TF was quantitated by surface plasmon resonance(SPR).The ability of EGFP-EGF1 in triggering coagulation was tested by prothrombin time assay.The FCM res...

Down-regulation of Tissue Factor by siRNA Increased Doxorubi-cin-induced Apoptosis in Human Neuroblastoma

The effects of tissue factor （TF） on doxorubicin-induced apoptosis in human neuroblastoma were investigated. The expression of TF was examined by Western blotting. TFsiRNA-pSUPER plasmid was constructed by inserting specific 19-nt silencing sequence targeting TF gene into pSUPER vector. Transfection of TFsiRNA-pSUPER was performed using lipofectamine^2000. The cytotoxicity of doxorubicin was determined by WST assay. The activation of Caspase-3 and PARP induced by doxorubicin was tested by Western blotting. The apoptotic cells were stained by Hochest33342 and counted under fluorescence inverted microscope. It was found that human neuroblastoma cell line SK-N-MC expressed high level of TE Knockdown of the TF expression was achieved by transfection of TFsiRNA-pSUPER on SK-N-MC cells in a dose-dependent manner. Inhibition of TF significantly decreased the viability of transfected SK-N-MC cells treated with different concentrations of doxorubicin. Cleavage of Caspase-3 and PARP was enhanced in transfected SK-N-MC cells with down-regulation of TF. TFsiRNA treatment significantly increased the number of apoptotic cells in transfected SK-N-MC cells as compared with those control cells （P〈0.05） when these cells were exposed to 1 μg/mL doxorubicin for 8 h. These results suggested that knockdown of the TF expression by specific siRNA vector could increase the cytotoxicity of doxorubicin and enhance doxorubicin-induced apoptosis in human neuroblastoma cells. Over-expression of TF might contribute to chemotherapy resistance in human neuroblastoma and its progression, at lest in part, by regulating doxorubicin-induced apoptosis.

Testosterone alleviates tumor necrosis factor-alpha-mediated tissue factor pathway inhibitor downregulation via suppression of nuclear factor-kappa B in endothelial cells

We have observed earlier that testosterone at physiological concentrations can stimulate tissue factor pathway inhibitor(TFPI)gene expression through the androgen receptor in endothelial cells.This study further investigated the impact of testosterone on TFPI levels in response to inflammatory cytokine tumor necrosis factor-alpha(TNF-α).Cultured human umbilical vein endothelial cells were incubated in the presence or absence of testosterone or TNF-α.TFPI protein and mRNA levels were assessed by enzyme-linked immunosorbent assay and quantitative real-time reverse transcription polymerase chain reaction.To study the cellular mechanism of testosterone’s action,nuclear factor-kappa B(NF-κB)translocation was confirmed by electrophoretic mobility shift assays.We found that after NF-κB was activated by TNF-α,TFPI protein levels declined significantly by 37.3%compared with controls(P<0.001),and the mRNA levels of TFPI also decreased greatly(P<0.001).A concentration of 30 nmol L-1 testosterone increased the secretion of TFPI compared with the TNF-α-treated group.NF-κB DNA-binding activity was significantly suppressed by testosterone(P<0.05).This suggests that physiological testosterone concentrations may exert their antithrombotic effects on TFPI expression during inflammation by downregulating NF-κB activity.

Beneficial effect of refined red palm oil on lipid peroxidation and monocyte tissue factor in HCV-related liver disease： a randomized controlled study

BACKGROUND： A large amount of endotoxin can be detected in the peripheral venous blood of patients with liver cirrhosis, contributing to the pathogenesis of hepatotoxicity because of its role in oxidative stress. The present study aimed to test the effect of the supplementation with red palm oil（RPO）, which is a natural oil obtained from oil palm fruit（Elaeis guineensis） rich in natural fat-soluble tocopherols, tocotrienols and carotenoids, on lipid peroxidation and endotoxemia with plasma endotoxin-inactivating capacity, proinflammatory cytokines profile, and monocyte tissue factor in patients with chronic liver disease. METHODS： The study group consisted of sixty patients（34 males and 26 females; mean age 62 years, range 54-75） with Child A/B, genotype 1 HCV-related cirrhosis without a history of ethanol consumption, randomly enrolled into an 8-week oral daily treatment with either vitamin E or RPO. All patients had undergone an upper gastrointestinal endoscopy 8 months before, and 13 out of them showed esophageal varices.RESULTS： Both treatments significantly decreased erythrocyte malondialdehyde and urinary isoprostane output, only RPO significantly affected macrophage-colony stimulating factor and monocyte tissue factor. Liver ultrasound imaging did not show any change. CONCLUSIONS： RPO beneficially modulates oxidative stress and, not least, downregulates macrophage/monocyte inflammatory parameters. RPO can be safely advised as a valuable nutritional implementation tool in the management of chronic liver diseases.

Anisodamine Inhibits Endotoxin-induced Tissue Factor Expression in Human Endothelial Cells

By study on the effect of anisodamine on lipopolysaccharide- induced expression of tissue factor(TF) in vascular endothelial cells(EC) ,the mechanism of anisodam ine antithrom bosis,as well as in the treatm ent of bacteraemic shock was investigated.Human umbilical vein endothelial cells (HUVECs) were cultured by trypsin digestion m ethod.TF activity was measured in the lysates of HUVEC by using a single step clotting assay.Specific m RNA expression was detected by Northern blotting.In order to evaluate a possible contribution of the nuclear factor (NF) -κB pathway on the effects observed,electrophoretic mobility shift assays(EMSA) were performed using nuclear extracts from HU VECs and NF- κB- binding oligonucleotides.The results showed that treatment of HUVEC with L PS resulted in a significant increase in TF activity.Anisodamine dose- dependently inhibited L PS- induced upregulation of TF.These effects was also confirm ed on the level of specific TF m RNA expression by Northern blotting.Furtherm ore,EMSA showed that anisodamine com pletely abolished L PS- induced NF-κB DNA binding activity in nuclear ex- tracts from HUVECs treated with L PS together with anisodamine.The results suggest thataniso- damine counteracts endothelial cell activation by inhibiting L PS- induced TF expression in these cells.Its interference with the NF- κB pathway might- at least in part- contribute to this effect. The ability of anisodamine to counteract L PS effect on endothelial cells m ight be one underlying m echanism explaining its antithrombosis and efficacy in the treatment of bacteraemic shock.

Expression and Location of Intracellular Tissue Factor in Atherosclerosis Stable Plaque of ApoE^(-/-) Mice

In the ApoE^-/- mouse model of atherosclerosis （AS） stable plaque, the expression and location of intracellular tissue factor （TF） in the cellular components of AS stable plaque were investigated in order to explore the cellular mechanism of AS thrombosis. Pathological changes of the stable plaque were observed under a microscope. The expression of TF protein was examined in aortic stable plaque of mice by using immunohistochemistry. Color image planimetric system was used to analyze the histological components of the stable plaque and the TF distribution. Under the confocal microscope, the intracellular TF location in the stable plaque of mice was observed. The results showed the cellular area was the major part of stable plaque （67.36%±6.52%, P〈0.01）. The percentage of total area occupied by cellular area was significantly larger than atheromatous gruel and acellular area （P〈0.01）. Macrophages and smooth muscle cells （SMC） were major cells in the cellular area. The percentage of total area occupied by SMC was significantly larger than by macrophages （P〈0.01）. Multiple linear regression analysis showed there was a positive correlation between TF area and SMC area （r=0.616, P=-0.008）, and no correlation was found between TF area and macrophage area （r=0.437, P=0.08）. Pictures of color image planimetric analysis of TF and SMC were merged to highlight areas with co-localization （yellow）, it was concluded that the process could be a cell-mediated TF expression in the stable plaque. SMC may be the major source of TF in AS without plaque rupture.

Protection of tight junction between RPE cells with tissue factor targeting peptide

AIM：To investigate the effect of tissue factor targeting peptide（TF-TP）on retinal pigment epithelium（RPE）cells tight junctions.METHODS：Cell counting kit-8（CCK-8）was used to measure the proliferation of ARPE-19 cells.Expression of tight junction,ZO-1 in ARPE-19 cells was measured by Western blot and immunofluorescent staining.Western blot was also used to detect the expression of tissue factor（TF）.CEC Transmigration Assay was used to measure the migration of ARPE-19 cells.The transport of fluorescent markers [fluorescein isothiocyanate dextrans of 4,10,20（FD4,FD10,FD20） ]and the transepithelial electrical resistance（TEER）were used to measure in ARPE-19 cell RESULTS：CCK-8 assay showed that 5μmol/L TF-TP can inhibit ARPE-19 cells abnormally proliferation stimulated by lipopolysaccharide（LPS;P〈0.05）.LPS increased the transport of fluorescent markers（FD4,FD10,FD20）and decreased TEER levels in ARPE-19 cells,respectively,which were prevented by 5μmol/L TF-TP pretreatment（P〈0.05）. Furthermore,LPS significantly up-regulated the expression of TF and downregulated the expression of ZO-1（P〈0.05）in ARPE-19 cell which was inhibited by the TF-TP（P〈0.05）.In addition,TF-TP inhibited the abnormal migration induced by LPS in ARPE-19 cell（P〈0.05）.CONCLUSION：Our findings suggest that TF-TP suppressed proliferation and migration of ARPE-19 cells induced by LPS,and maintained the RPE tight junctions through inhibition of TF expression and increased expression of ZO-1.

Ligand Induced Conformational Transitions of Tissue Factor ? Loop

Tissue factor（TF）, the cell surface receptor and requisite cofactor for the inactive serine protease factor VⅡa（VⅡa）, binds VⅡa and its zymogen factor VⅡ with picomolar affinity on the cell surface. The TF：VⅡa complex proteolytically converts downstream zymogen factors X and IX to their active protease states in the cascade responsible for thrombogenesis and hemostasis. The TF pathway also produces cellular signaling through protease activated receptors. Here we present a crystal structure of the completely intact surface domain of TF in complex with VⅡa that reveals a significant conformational difference as compared to free TF. A long loop of residue 78~91 of the tissue factor（named Ω loop here） was found to have well-ordered conformation, whereas this loop in free TF has an expanded conformation and is largely disordered. This loop adopts a tight conformation consisting of five β turns in the TF：VⅡa complex. The Ω loop is located at the interface of the proteins of the complex, has a few interactions with VⅡa, and is possible to accommodate the sequence variations of TF in different mammalian species.

Role of tissue factor in hepatocellular carcinoma genesis, invasion and metastasis

Background Numerous studies indicate that tissue factor （TF）, namely tissue thromboplastin, has a close relationship with malignant tumor genesis and progress. It contributes to blood coagulation as well as the regulation of cellular differentiation, the formation of blood vessels, and also tumor recurrence and metastasis. The present study aimed to detect TF expression in hepatocellular carcinoma （HCC） patients and to elucidate its association with prognosis and clinical features of the disease. Methods The plasma TF levels of 50 HCC patients and 30 controls were assayed by ELISA. The expressions of TF mRNA and protein in HCC tissues, adjacent tissues and normal tissues were detected by reverse transcription- polymerase chain reaction （RT-PCR） and Western blotting. The acquired data were analyzed with related clinic-pathological documents. The patients were followed up for five years, and the relationship between TF and prognosis was analyzed. Results The plasma TF levels were significantly increased in HCC compared to the controls （P 〈0.05）, presenting a close relationship with differentiation level, tumor size and hepatocirrhosis occurrence （P 〈0.05）. There were remarkably higher values in cases of lymphatic metastasis, extrahepatic metastasis and portal tumor thrombus （PTT） （P 〈0.05） compared to non-metastasis or non-tumor thrombus, but no significant difference with different focus number or envelope （P 〉0.05）. The positive rates and the relative expression of TF mRNA in HCC tissue were 63.0% （17/27） and 0.567±0.268, respectively, significantly higher than that in adjacent tissues or normal tissues （P 〈0.05）. In the patients with positive results, the relative expression intensity varied significantly with different tumor size and index of local invasion and metastasis （P 〈0.05）. The positive rates and the relative expression intensities of TF protein in HCC tissue were 74.1% （20/27） and 4.093±1.256, respectively, significantly higher than those in adjacent tissue or normal tissue （P 〈0.05）. In the patients with positive results, the relative expression intensity showed significant difference in different tumor size, differentiation level, and index of local invasion and metastasis （P 〈0.05）. Conclusions The TF levels were significantly higher in plasma and tissues of HCC patients, presenting a close relationship with the index of invasion and metastasis. It indicated that TF might be related to differentiation and metastasis of HCC.

The effect of celecoxib on tissue factor expression in pancreatic cancer cells

Background Tissue factor （TF） is overexpressed in many malignant tumours and is linked to the pathogenesis and prognosis of such malignancies. In vitro studies have proved that reduced expression of TF has inhibitory effect on the angiogenesis and cell proliferation of the malignant tumour. Therefore, TF suppression has been raised as a possible treatment for malignant tumours. Here we investigated the effect of celecoxib on TF expression induced by tumour necrosis factor α （TNFα） in PANC-1 cells and a possible molecular mechanism underlvina the celecoxib effect.Methods Various doses of celecoxib solution were added to standard cell numbers of PANC-1 cells mixed with equal dose of TNFα for 6 hours. The expression of tissue factor was detected quantitatively by Western blot, whilst the activation of nuclear factor κB was tested by electromobility shift assay.Results As the doses of celecoxib increased, the tissue factor expression was decreased in PANC-1 cells and so was the activation of nuclear factor κB.Conclusions Celecoxib can downregulate the expression of tissue factor induced by TNFα in PANC-1 cells. This antitumour effect of celecoxib can be explained indirectly via its suppressive role in activation of nuclear factor κB.

ACTIVATION OF BOVINE FACTOR IX BY THE REACTION PRODUCT OF BOVINE FACTOR VII AND HUMAN TISSUE FACTOR

A study was carried out on the alternate activation of factor IX （FIX） by bovine FVII and human tissue factor （TF） rather than by activated factor XI （FXI）. The reaction product of bovine FVII and human TF functioned as a FIX activator in the assay system used. Published studies suggest that in the presence of Caions, the complex of human FVII-TF readily activates both human FIX and human FX,and at low TF concentrations, FIX appears to be the preferred substrate for the reaction product of FVII and TF. This may explain the discrepancy between the mild bleeding of hereditary FXI deficiency and the severe bleeding of hereditery FIX deficieney. The results obtained with bovine FVII and a crude human TF preparation confirm that at low TF concentrations,bovine FIX is the preferred substrate rather than FX. At higher TF concentrations, bovine FX was rapidly activated.

Oxidized low density lipoprotein inhibited tissue factor pathway inhibitor mRNA expression in human endothelial cells

To understand the role of oxidized low density lipoprotein (OX LDL) in the pathogenesis of thrombotic complications in atherogenesis Methods Low density lipoprotein was isolated from normal heparinized blood by density gradient ultracentrifugation and oxidized by CuCl 2 Total RNA was extracted from human umbilical vein endothelial cells (HUVECs) exposed to LDL or OX LDL, using the guanidinium isothiocyanate method The quantification of tissue factor pathway inhibitor (TFPI) mRNA in HUVECs was carried out by reverse transcriptase polymerase chain reaction (RT PCR) Results HUVECs were able to express TFPI mRNA constitutively The expression was not affected by LDL but was effectively inhibited by OX LDL in a time and dose dependent manner Conclusions The results suggest that oxidized LDL may play an important role in inducing coagulation in atherosclerotic lesions by the inhibition of expression of TFPI in vascular endothelial cells

Characterization of a novel bispecific antibody targeting tissue factor-positive tumors with T cell engagement

T cell engaging bispecific antibody(TCB)is an effective immunotherapy for cancer treatment.Through co-targeting CD3 and tumor-associated antigen(TAA),TCB can redirect CD3+T cells to eliminate tumor cells regardless of the specificity of T cell receptor.Tissue factor(TF)is a TAA that involved in tumor progression.Here,we designed and characterized a novel TCB targeting TF(TF-TCB)for the treatment of TF-positive tumors.In vitro,robust T cell activation,tumor cell lysis and T cell proliferation were induced by TF-TCB.The tumor cell lysis activity was dependent upon both CD3 and TF binding moieties of the TF-TCB,and was related to TF expression level of tumor cells.In vivo,in both tumor cell/human peripheral blood mononuclear cells(PBMC)co-grafting model and established tumor models with poor T cell infiltration,tumor growth was strongly inhibited by TF-TCB.T cell infiltration into tumors was induced during the treatment.Furthermore,efficacy of TF-TCB was further improved by combination with immune checkpoint inhibitors.For the first time,our results validated the feasibility of using TF as a target for TCB and highlighted the potential for TF-TCB to demonstrate efficacy in solid tumor treatment.

Molecularly engineered truncated tissue factor with therapeutic aptamers for tumor-targeted delivery and vascular infarction

Selective occlusion of tumor vasculature has proven to be an effective strategy for cancer therapy.Among vascular coagulation agents,the extracellular domain of coagulation-inducing protein tissue factor,truncated tissue factor(tTF),is the most widely used.Since the truncated protein exhibits no coagulation activity and is rapidly cleared in the circulation,free tTF cannot be used for cancer treatment on its own but must be combined with other moieties.We here developed a novel,tumor-specific tTF delivery system through coupling tTF with the DNA aptamer,AS1411,which selectively binds to nucleolin receptors overexpressing on the surface of tumor vascular endothelial cells and is specifically cytotoxic to target cells.Systemic administration of the tTF-AS1411 conjugates into tumor-bearing animals induced intravascular thrombosis solely in tumors,thus reducing tumor blood supply and inducing tumor necrosis without apparent side effects.This conjugate represents a uniquely attractive candidate for the clinical translation of vessel occlusion agent for cancer therapy.

Endogenous tissue factor pathway inhibitor in vascular smooth muscle cells inhibits arterial thrombosis

Tissue factor pathway inhibitor （TFPI） is the main inhibitor of tissue factor-mediated coagulation. TFPI is expressed by endothelial and smooth muscle cells in the vasculature. Endothefium-derived TFPI has been reported to play a regulatory role in arterial thrombosis. However, the role of endogenous TFPI in vascular smooth muscle cells （VSMCs） in thrombosis and vascular disease development has yet to be elucidated. In this TFPI^Flox mice crossbred with Sma-Cre mice were utilized to establish TFPI conditional knockout mice and to examine the effects of VSMC-directed TFPI deletion on development, hemostasis, and thrombosis. The mice with deleted TFPI in VSMCs （TFP^Sma） reproduced viable offspring. Plasma TFPI concentration was reduced 7.2% in the TFPIsma mice compared with TFPI^Flox littermate controls. Plasma TFPI concentration was also detected in the TFPI^Tle2 （mice deleted TFPI in endothefial ceils and cells of hematopoietic origin） mice. Plasma TFPI concentration of the TFPI^Tle2 mice was 80.4% lower （P 〈 0.001） than that of the TFPI^Flox mice. No difference in hemostatic measures （PT, APTT, and tail bleeding） was observed between TFPIsma and TFPI^Flox mice. However, TFP^Sma mice had increased ferric chloride-indueed arterial thrombosis compared with TFPI^Flox littermate controls. Taken together, these data indicated that endogenous TFPI from VSMCs inhibited ferric chloride-induced arterial thrombosis without causing hemostatic effects.

Effect of Reduqing (热毒清) on Endotoxin-Induced Production of Tissue Factor and Cytokines in Human Whole Blood

Objective: TO study the effect of Reduqing (RDQ) Injection on the lipopolysaccharide (LPS)induced tissue factor and cytokine production in whole blood. Methods: Heparinized human blood was incubated with LPS in the presence or absence of RDQ. The plasma concentrations of TNF-α, IL-1β, IL-6, and IL-8were measured by enzyme-linked immunosorbent assays (ELISA) and the monocyte tissue factor activity wasmeasured by a one-stage tissue factor induced plasma clotting time assay. Results: RDQ was found to diminishthe LPS-induced increase of TNF-α, IL-1β and IL-6 in plasma but did not completely abolish their production.In contrast to the effect on these cytokines, RDQ caused further increase of the plasma level of IL-8 and themonocyte TF activity in the presence of LPS. Conclusions: In the in vztro whole blood assay system used inthis study, the decrease of LPS-induced production of TNF-α, IL-1β, and IL-6 was similar to a previous in vivostudy on the effect of RDQ on the production of these cytokines in response to two-time LPS injection in rabbits, while the increase of IL-8 and TF production was contradictory to the previous in vivo study. Potentialreasons contributing to the differences are discussed.

Research progress on the role of connective tissue growth factor in fibrosis of diabetic retinopathy

Diabetic retinopathy（DR） is one of the most important types of diabetic microangiopathy, which is a specific change of fundus lesions and is one of the most serious complications of diabetes. When DR develops to proliferative DR, the main factors of decreasing vision, and even blindness, include retinal detachment and vitreous hemorrhage caused by contraction of blood vessels by fiber membrane. Recent studies reported that the formation of fiber vascular membrane is closely related to retinal fibrosis. The connective tissue growth factor（CTGF） is a cytokine that is closely related to DR fibrosis. However, its mechanism is poorly understood. This paper summarizes the recent studies about CTGF on DR fibrosis for a comprehensive understanding of the role and mechanism of CTGF in PDR.