Intercellular Adhesion Molecule-1 Activity Research Articles

IFNγ-primed periodontal ligament cells regulate T-cell responses via IFNγ-inducible mediators and ICAM-1-mediated direct cell contact.

Periodontal ligament (PDL) cells help maintain tissue homeostasis by balancing PDL tissue inflammation and regeneration. However, the mechanisms by which interferon γ (IFNγ) modulate this process are not yet fully understood. The present study aimed to examine the effect of primed and non-primed PDL cells with IFNγ on the viability and differentiation of T lymphocytes and its functional consequences. The results showed that IFNγ-primed PDL cells possessed enhanced immunosuppression by suppressing T-lymphocyte viability and directing T-lymphocyte differentiation towards a higher T helper (Th) Th2/Th1 ratio. Suppression of T-cell viability was mainly mediated by IFNγ-inducible secreted mediators, which was prevented in the presence of direct cell contact, probably by intercellular adhesion molecule-1 (ICAM-1)-induced PI3 K-mediated transforming growth factor β1 expression in PDL cells. By contrast, ICAM-1 activation augmented IFNγ-induced IFNγ and interleukin-6 expression in PDL cells, which in turn modulated T-cell differentiation. The resulting interaction between these two cell types activated macrophage and suppressed osteoclast differentiation. In conclusion, the results have shown, for the first time to our knowledge, that primed and non-primed PDL cells with IFNγ differentially control T-cell responses via IFNγ-inducible mediators and ICAM-1-mediated direct cell contact, suggesting the role of PDL cells in shifting an inflammatory phase towards a regenerative phase.

Bioactive Evaluation of Ursane-Type Pentacyclic Triterpenoids: β-Boswellic Acid Interferes with the Glycosylation and Transport of Intercellular Adhesion Molecule-1 in Human Lung Adenocarcinoma A549 Cells.

Ursane-type pentacyclic triterpenoids exert various biological effects, including anticancer and anti-inflammatory activities. We previously reported that ursolic acid, corosolic acid, and asiatic acid interfered with the intracellular trafficking and glycosylation of intercellular adhesion molecule-1 (ICAM-1) in human lung adenocarcinoma A549 cells stimulated with the pro-inflammatory cytokine interleukin-1α. However, the structure–activity relationship of ursane-type pentacyclic triterpenoids remains unclear. In the present study, the biological activities of seven ursane-type pentacyclic triterpenoids (β-boswellic acid, uvaol, madecassic acid, 3-O-acetyl-11-keto-β-boswellic acid, ursolic acid, corosolic acid, and asiatic acid) were investigated. We revealed that the inhibitory activities of ursane-type pentacyclic triterpenoids on the cell surface expression and glycosylation of ICAM-1 and α-glucosidase activity were influenced by the number of hydroxy groups and/or the presence and position of a carboxyl group. We also showed that β-boswellic acid interfered with ICAM-1 glycosylation in a different manner from other ursane-type pentacyclic triterpenoids.

Bacillus subtilis Spore-Trained Dendritic Cells Enhance the Generation of Memory T Cells via ICAM1.

Immunological memory is a cardinal feature of the immune system. The intestinal mucosa is the primary exposure and entry site of infectious organisms. For an effective and long-lasting safeguard, a robust immune memory system is required, especially by the mucosal immunity. It is well known that tissue-resident memory T cells (Trms) provide a first response against infections reencountered at mucosal tissues surfaces, where they accelerate pathogen clearance. However, their function in intestinal immunization remains to be investigated. Here, we report enhanced local mucosal and systemic immune responses through oral administration of H9N2 influenza whole inactivated virus (H9N2 WIV) plus Bacillus subtilis spores. Subsequently, H9N2 WIV plus spores led to the generation of CD103+ CD69+ Trms, which were independent of circulating T cells during the immune period. Meanwhile, we also found that Bacillus subtilis spores could stimulate Acrp30 expression in 3T3-L1 adipocytes. Moreover, spore-stimulated adipocyte supernatant also upregulated the expression of intercellular adhesion molecule-1 (ICAM1) in dendritic cells (DCs). Furthermore, the proportion of HA-tetramer+ cells was severely curtailed upon suppressed ICAM1 expression, which also depended on HA-loaded DCs. Taken together, our data demonstrated that spore-promoted H9N2 WIV induced an immune response by enhancing Trms populations, which were associated with the activation of ICAM1 in DCs.

Neferine suppresses vascular endothelial inflammation by inhibiting the NF-κB signaling pathway

The vascular endothelium, as the interface between the blood and the surrounding tissues, plays a pivotal role in inflammation. Neferine, which was isolated from Lotus Plumule, has many biological roles, such as antifibrotic, antioxidative, anti-inflammatory, and antineoplastic activities. We demonstrated the role of neferine in the inhibition of pro-adhesion and pro-inflammatory responses of endothelial cells in vitro. We found that neferine could significantly inhibit the adhesion of Tohoku Hospital Pediatrics-1 (THP-1) cells to primary human umbilical vein endothelial cells (HUVECs). At the molecular level, neferine could significantly alleviate the interleukin 1β (IL-1β)-induced mRNA and protein expression of intercellular adhesion molecule 1 (ICAM1) and vascular cell adhesion molecule 1 (VCAM1). Our data showed that neferine suppressed nuclear factor-κB (NF-κB) nuclear translocation and inhibited the NF-κB-p65-induced transcriptional activity of ICAM1 and VCAM1. Therefore, we concluded that neferine suppressed the inflammatory response in endothelial cells in vitro, which could be mainly due to inhibition of NF-κB signaling activation. Moreover, we found that neferine alleviated LPS-induced acute inflammation injury in vivo. Thus, neferine may serve as an effective regulator during the pathogenesis of vascular inflammatory diseases.

Drimenol, isodrimeninol and polygodial isolated from Drimys winteri reduce monocyte adhesion to stimulated human endothelial cells

The vascular endothelium is a continuous monolayer of endothelial cells that are in direct contact with the blood and its dysfunction is the starting process in the development of many pathological inflammatory disorders, such as atherosclerosis, which can result in death. The expression of adhesion molecules such as vascular cell adhesion molecule 1 (VCAM1) and intercellular adhesion molecule 1 (ICAM1) is a key stage in modulating vascular inflammation, where the adhesion of monocytes and their transmigration into the intima starting a cascade of inflammatory reactions. Looking for natural compounds with inhibitory activity of VCAM1 and ICAM1, we isolated drimenol, isodrimeninol and polygodial as the main secondary metabolites from barks of Drimys winteri (Dw) and evaluated their effects in the adhesion response of monocytes cells (THP1) to a monolayer of human umbilical vein endothelial cells (HUVEC) in coculture assays. The results showed that the molecules and total extract Dw decrease the adhesion of THP1 to HUVECs, at 10 μg/mL. The adhesion activity is explained due to the inhibition of VCAM1 and ICAM1 evidenced by qRT-PCR and Western-blot assays. In conclusion, drimane sesquiterpenoids could be used as a molecular scaffold in the development of drugs for inflammatory vascular diseases.

Study of Intercellular Adhesion Molecule-1 (ICAM-1) in Bone Homeostasis.

Although studies have established the role of integrins in bone homeostasis, especially in osteoclastogenesis, and these molecules are novel and promising therapeutic drug targets for bone loss diseases, such as: osteolysis, the cellular mechanism still elusive. Bone homeostasis takes place through the interaction of bone cells (osteoblasts and osteoclast) via the activation of intercellular adhesion molecule-1 (ICAM-1), which is a critical submolecule of integrin. In the present study, we reviewed several novel studies on integrins and their submolecule, ICAM-1, in bone homeostasis. In order to demonstrated that ICAM-1 might exert dual effects on osteoclastogenesis by directly affecting the adhesive ability of mature osteoclasts and indirectly participating in RANKL/RANK induced osteoclastic precursors differentiation. Although these results still need to be verified in the future, the extending study about the role of ICAM-1 in osteoclastogenesis will cerntainly provide a promising therapeutic target for the treatment of bone loss diseases.

Non-invasively enhanced intracranial transplantation of mesenchymal stem cells using focused ultrasound mediated by overexpression of cell-adhesion molecules.

Although there have been reports of promising results regarding the transplantation of mesenchymal stem cells (MSCs) for neurodegenerative diseases through the use of neuronal differentiation or control of the microenvironment, traditional surgical transplantation methods like parenchymal or intravenous injection have limitations such as secondary injuries in the brain, infection, and low survival rate of stem cells in the target site. Focused ultrasound (FUS) treatment is an emerging modality for the treatment of brain diseases, including neurodegenerative disorders. The various biological effects of FUS treatment have been investigated; therefore, the goal is now to improve the delivery efficiency and function of MSCs by capitalizing on the advantages of FUS. In this study, we demonstrated that FUS increases MSC transplantation into brain tissue by >2-fold, and that this finding might be related to the activation of intercellular adhesion molecule-1 in endothelial and subendothelial cells and vascular adhesion molecule-1 in endothelial cells.

ICAM-1 promotes the abnormal endothelial cell phenotype in chronic thromboembolic pulmonary hypertension.

Pulmonary endothelial cells play a key role in the pathogenesis of Chronic Thromboembolic Pulmonary Hypertension (CTEPH). Increased synthesis and/or the release of intercellular adhesion molecule-1 (ICAM-1) by pulmonary endothelial cells of patients with CTEPH has been recently reported, suggesting a potential role for ICAM-1 in CTEPH. We studied pulmonary endarterectomy specimens from 172 patients with CTEPH and pulmonary artery specimens from 97 controls undergoing lobectomy for low-stage cancer without metastasis. ICAM-1 was overexpressed in vitro in isolated and cultured endothelial cells from endarterectomy specimens. Endothelial cell growth and apoptosis resistance were significantly higher in CTEPH specimens than in the controls (p < 0.001). Both abnormalities were abolished by pharmacological inhibition of ICAM-1 synthesis or activity. The overexpression of ICAM-1 contributed to the acquisition and maintenance of abnormal EC growth and apoptosis resistance via the phosphorylation of SRC, p38 and ERK1/2 and the overproduction of survivin. Regarding the ICAM-1 E469K polymorphism, the KE heterozygote genotype was significantly more frequent in CTEPH than in the controls, but it was not associated with disease severity among patients with CTEPH. ICAM-1 contributes to maintaining the abnormal endothelial cell phenotype in CTEPH.

Association between K469E polymorphism of ICAM‐1 gene and susceptibility of ischemic stroke: An updated meta‐analysis

BackgroundThe intercellular adhesion molecule‐1 (ICAM‐1)/leukocyte function associated antigen‐1 (LFA‐1) adhesion system regulates leukocyte interactions, migration, and adhesion, and appears to play an important role in atherosclerosis and thrombosis. Therefore, single nucleotide polymorphisms (SNPs) of the ICAM‐1 gene may strongly influence the expression and biological activity of ICAM‐1 and play a potentially important role in the pathogenesis of ischemic stroke. In the current meta‐analysis, we investigated the relationship between the ICAM‐1 gene K469E SNP and the risk of ischemic stroke.MethodsTwo investigators independently searched PubMed, Web of Science, Google Scholar, WANFANG, China National Knowledge Infrastructure (CNKI) and J‐STAGE for studies published from January 2000 to February 2019 without language restriction. The association of K469E polymorphism and ischemic stroke in three genetic models (allelic, recessive, and dominant) were evaluated using Pooled odds ratios (ORs) with 95% confidence intervals (CIs).ResultsOur study included 20 studies from four continents and four different countries, including 3,137 cases and 15,382 controls. Meta‐analysis results did not show a significant association between K469E polymorphism of ICAM‐1 gene and ischemic stroke when assuming allelic model (OR: 1.12; 95% CI: 0.8 to 1.55; p = 0.51; I 2 = 93%) or recessive model (OR: 1.28; 95% CI: 0.89 to 1.84; p = 0.18; I 2 = 82%) or dominant model (OR: 1.20; 95% CI: 0.92 to 1.56; p = 0.17; I 2 = 85%). However, in all three genetic models, subgroup analysis revealed that the K469E polymorphism of the ICAM‐1 gene is associated with ischemic stroke in the Caucasian population.ConclusionK469E polymorphism of ICAM‐1 gene might be a risk factor for ischemic stroke in Caucasians, which suggested that K469E polymorphism might help in early identification of those at risk and help in primary prevention of ischemic stroke.

Effects of glutamine on cytokines 1L-1 and TNF-α in rehabilitation and prognosis of patients with lobectomy.

This study was designed to investigate the effects of glutamine on cytokines 1L-1, TNF-α and prognosis of patients with lobectomy in the process of postoperative rehabilitation. A total of 78 patients with lung cancer who underwent lobectomy from January 2015 to January 2017 were selected in Daqing Oilfield General Hospital (Daqing, China). Patients were randomly divided into two groups, 39 patients in each group. Patients in the control group were treated with conventional treatment, while patients in the observation group were treated with both conventional and glutamine treatment. The levels of TNF-α, endotoxin, serum IL-1, IL-10, IL-15, IL-18 and intercellular adhesion molecule-1 (ICAM-1), myeloperoxidase (MPO) activity, incidence of nausea and vomiting, pulmonary histopathological changes, prognosis, and rehabilitation (time in bed, hospital stay and lung function) were compared between the two groups. Within 1 year after treatment, most patients survived, except 2 patients in the observation group and 3 patients in the control group who died. The rate of postoperation infection in the observation group was slightly lower than that in the control group. After treatment, the levels of endotoxin and TNF-α in the observation group were significantly lower than those in the control group (p<0.05). After treatment, the serum levels of IL-1 and IL-10 were significantly higher and the serum levels of IL-15 and IL-18 were significantly lower in the observation group than those in the control group (p<0.05). The expression levels of ICAM-1 and MPO activity were significantly higher in the observation group than those in the control group (p<0.05). No significant difference in the incidence of nausea and vomiting was found between the two groups (p>0.05). The average postoperative bed rest and hospital stay in the observation group were significantly shorter than those in the control group (p<0.05). The levels of forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC) and peak expiratory flow rate (PEFR) in the observation group were significantly higher than those in the control group (p<0.05). The results indicated that glutamine treatment is effective in the postoperative rehabilitation of patients undergoing lobectomy. Glutamine can regulate the levels of IL-1 and TNF-α, improve lung function, shorten bed rest and hospitalization days, promote patients postoperative rehabilitation process, and improve patients quality of life.

Advanced glycation end-products increase IL-6 and ICAM-1 expression via RAGE, MAPK and NF-κB pathways in human gingival fibroblasts.

Diabetes mellitus (DM) is a risk factor for periodontal diseases and may exacerbate the progression of the pathogenesis of periodontitis. Advanced glycation end-products (AGEs) cause DM complications relative to levels of glycemic control and larger amounts accumulate in the periodontal tissues of patients with periodontitis and DM. In the present study, we investigated the effects of AGEs on the expression of inflammation-related factors in human gingival fibroblasts (HGFs) to elucidate the impact of AGEs on DM-associated periodontitis. HGFs were cultured with or without AGEs. Cell viability was examined, and RNA and protein fractions were isolated from AGE-treated cells. The expression of interleukin (IL)-6, intercellular adhesion molecule-1 (ICAM-1), and the receptor for AGE (RAGE) was investigated using reverse transcription-polymerase chain reaction, quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay, and reactive oxygen species activity was measured using a kit with 2',7'-dichlorofluorescin diacetate. Human monocytic cells (THP-1) labeled with a fluorescent reagent were co-cultured with HGFs treated with AGEs and IL-6 siRNA, and the adhesive activity of THP-1 cells to HGFs was assessed. The expression of IL-6 and ICAM-1 was examined when HGFs were pretreated with recombinant human IL-6, the siRNAs of RAGE and IL-6, and inhibitors of MAPK and NF-κB, and then cultured with and without AGEs. The phosphorylation of MAPK and NF-κB was assessed using western blotting. AGEs increased the mRNA and protein expressions of RAGE, IL-6, ICAM-1 and reactive oxygen species activity in HGFs, and promoted the adhesion of THP-1 cells to HGFs, but had no effect on cell viability until 72hours. Recombinant human IL-6 increased ICAM-1 expression in HGFs, while the siRNAs of RAGE and IL-6 inhibited AGE-induced IL6 and ICAM1 mRNA expression, and IL-6 siRNA depressed AGE-induced THP-1 cell adhesion. AGEs increased the phosphorylation of p38 and ERK MAPKs, p65 NF-κB and IκBα, while inhibitors of p38, ERK MAPKs and NF-κB significantly decreased AGE-induced IL-6 and ICAM-1 expression. AGEs increase IL-6 and ICAM-1 expression via the RAGE, MAPK and NF-κB pathways in HGFs and may exacerbate the progression of the pathogenesis of periodontal diseases.

Endothelial cell SHP-2 negatively regulates neutrophil adhesion and promotes transmigration by enhancing ICAM-1-VE-cadherin interaction.

Intercellular adhesion molecule-1 (ICAM-1) mediates the firm adhesion of leukocytes to endothelial cells and initiates subsequent signaling that promotes their transendothelial migration (TEM). Vascular endothelial (VE)-cadherin plays a critical role in endothelial cell-cell adhesion, thereby controlling endothelial permeability and leukocyte transmigration. This study aimed to determine the molecular signaling events that originate from the ICAM-1-mediated firm adhesion of neutrophils that regulate VE-cadherin's role as a negative regulator of leukocyte transmigration. We observed that ICAM-1 interacts with Src homology domain 2-containing phosphatase-2 (SHP-2), and SHP-2 down-regulation via silencing of small interfering RNA in endothelial cells enhanced neutrophil adhesion to endothelial cells but inhibited neutrophil transmigration. We also found that VE-cadherin associated with the ICAM-1-SHP-2 complex. Moreover, whereas the activation of ICAM-1 leads to VE-cadherin dissociation from ICAM-1 and VE-cadherin association with actin, SHP-2 down-regulation prevented ICAM-1-VE-cadherin association and promoted VE-cadherin-actin association. Furthermore, SHP-2 down-regulation in vivo promoted LPS-induced neutrophil recruitment in mouse lung but delayed neutrophil extravasation. These results suggest that SHP-2-via association with ICAM-1-mediates ICAM-1-induced Src activation and modulates VE-cadherin switching association with ICAM-1 or actin, thereby negatively regulating neutrophil adhesion to endothelial cells and enhancing their TEM.-Yan, M., Zhang, X., Chen, A., Gu, W., Liu, J., Ren, X., Zhang, J., Wu, X., Place, A. T., Minshall, R. D., Liu, G. Endothelial cell SHP-2 negatively regulates neutrophil adhesion and promotes transmigration by enhancing ICAM-1-VE-cadherin interaction.

Troxerutin Preconditioning and Ischemic Postconditioning Modulate Inflammatory Response after Myocardial Ischemia/Reperfusion Injury in Rat Model.

Protective effects of ischemic postconditioning in myocardial ischemia/reperfusion (I/R) injury have been ever demonstrated, but the exact mechanisms remain unclear. Because of their multiplex activities, using natural pharmaceuticals seems to be clinically interesting. The aim of present study was to investigate the effects of troxerutin preconditioning and ischemic postconditioning on inflammatory responses after myocardial I/R injury in a rat model. Twenty-four Wistar rats were divided into four groups as the control, troxerutin receiving (TXR), postconditioning receiving (PostC), and combined therapy (TXR + PostC). Rats' isolated hearts underwent 30-min LAD regional ischemia followed by 45-min reperfusion. Troxerutin was orally administered for a month before I/R. Ischemic PostC was applied by alternative three cycles of 30-s R/I at the onset of reperfusion. The coronary effluent and ischemic left ventricular samples were used to determine the activities of creatine kinase (CK), intercellular adhesion molecule-1 (ICAM-1), interlukin-1beta (IL-1β), tumor-necrosis factor (TNF-α), and also histopathological studies. Pretreatment of rats with troxerutin significantly reduced myocardial inflammatory cytokines TNF-α and IL-1β levels and ICAM-1 activity after I/R insult compared to those of control I/R hearts (P < 0.05). Application of PostC showed similar impacts on those parameters. In fact, anti-inflammatory mechanisms of both treatments were associated with their protective effects against myocardial damages causing from I/R injury. Pretreatment with troxerutin as well as postconditioning can induce cardioprotection through prevention of the cell-cell interaction and release of inflammatory mediators, minimizing I/R pathological changes in myocardial cells. These two treatments may share same mechanisms in their actions since they showed no significant additive effects.

Von Willebrand factor contributes to poor outcome in a mouse model of intracerebral haemorrhage.

Spontaneous intracerebral haemorrhage (ICH) is the most devastating stroke subtype and has no proven treatment. von Willebrand factor (VWF) has recently been demonstrated to promote inflammation processes. The present study investigated the pathophysiological role of VWF after experimental ICH. Functional outcomes, brain edema, blood-brain barrier (BBB) permeability, cerebral inflammation and levels of intercellular adhesion molecule-1 (ICAM-1) and matrix metalloproteinase-9 (MMP-9) were measured in a mouse model of ICH induced by autologous blood injection. We show that VWF were increased in the plasma and was accumulated in the perihematomal regions of mice subjected to ICH. Injection of VWF resulted in incerased expression of proinflammatory mediators and activation of ICAM-1 and MMP-9, associated with elevated myeloperoxidase, recruitment of neutrophils and microglia. Moreover, mice treated with VWF showed dramatically decreased pericyte coverage, more severe BBB damage and edema formation, and neuronal injury was increased compared with controls. In contrast, blocking antibodies against VWF reduced BBB damage and edema formation and improved neurological function. Together, these data identify a critical role for VWF in cerebral inflammation and BBB damage after ICH. The therapeutic interventions targeting VWF may be a novel strategy to reduce ICH-related injury.

Expression, production, and renaturation of a functional single-chain variable antibody fragment (scFv) against human ICAM-1.

Intercellular adhesion molecule-1 (ICAM-1) is an important factor in the progression of inflammatory responses in vivo. To develop a new anti-inflammatory drug to block the biological activity of ICAM-1, we produced a monoclonal antibody (Ka=4.19×10−8 M) against human ICAM-1. The anti-ICAM-1 single-chain variable antibody fragment (scFv) was expressed at a high level as inclusion bodies in Escherichia coli. We refolded the scFv (Ka=2.35×10−7 M) by ion-exchange chromatography, dialysis, and dilution. The results showed that column chromatography refolding by high-performance Q Sepharose had remarkable advantages over conventional dilution and dialysis methods. Furthermore, the anti-ICAM-1 scFv yield of about 60 mg/L was higher with this method. The purity of the final product was greater than 90%, as shown by denaturing gel electrophoresis. Enzyme-linked immunosorbent assay, cell culture, and animal experiments were used to assess the immunological properties and biological activities of the renatured scFv.

Sildenafil Attenuates Hepatocellular Injury after Liver Ischemia Reperfusion in Rats: A Preliminary Study

We evaluated the role of sildenafil in a rat liver ischemia-reperfusion model. Forty male rats were randomly allocated in four groups. The sham group underwent midline laparotomy only. In the sildenafil group, sildenafil was administered intraperitoneally 60 minutes before sham laparotomy. In the ischemia-reperfusion (I/R) group, rats were subjected to 45 minutes of hepatic ischemia followed by 120 minutes of reperfusion, while in the sild+I/R group rats were subjected to a similar pattern of I/R after the administration of sildenafil, 60 minutes before ischemia. Two hours after reperfusion, serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured and histopathological examination of the lobes subjected to ischemia as well as TUNEL staining for apoptotic bodies was performed. Additionally, myeloperoxidase (MPO) activity and the expression of intercellular adhesion molecule-1 (ICAM-1) were analyzed. Serum markers of hepatocellular injury were significantly lower in the sild+I/R group, which also exhibited lower severity of histopathological lesions and fewer apoptotic bodies, as compared to the I/R group. The I/R group showed significantly higher MPO activity and higher expression of ICAM-1, as compared to the sild+I/R group. Use of sildenafil as a preconditioning agent in a rat model of liver I/R exerted a protective effect.

Clock upregulates intercellular adhesion molecule-1 expression and promotes mononuclear cells adhesion to endothelial cells

Clock is a basic helix-loop-helix (bHLH) transcription factor that plays important role in circadian rhythms of various physiological functions. Previous study showed that the expression of intercellular adhesion molecule-1 (ICAM-1) was reduced in the liver tissues of Clock mutant mice. However, how Clock regulates ICAM-1 expression and whether Clock affects cell adhesion function remain unknown. In the present study, we found that exogenous expression of Clock upregulated the gene expressions of ICAM-1 and other adhesion-related genes including VCAM1 and CCL-2, and increased the transcriptional activity of ICAM-1 in mouse brain microvascular endothelial cell lines. In contrast, loss of Clock decreased these gene expressions and ICAM-1 transcriptional activity. Chromatin immunoprecipitation (ChIP) assay revealed that Clock binds to the E-box-like enhancer of ICAM-1 gene. ICAM-1 gene showed rhythmic expression in endothelial cells after serum shock in vitro, suggesting ICAM-1 may be a Clock-controlled gene. Clock regulates the adhesion of mononuclear cells to endothelial cells via ICAM-1. Together, our findings show that Clock is a positive regulator of ICAM-1, and promotes the adhesion of mononuclear cells to endothelial cells.

Markers of Coagulation Activation, Endothelial Stimulation, and Inflammation in Dogs with Babesiosis

Babesia infections in dogs can result in a wide range of clinical and laboratory presentations, including coagulopathy. Expression of intercellular adhesion molecule-1 (ICAM-1) and von Willebrand factor (vWF) in dogs with babesiosis is unknown. Whether inflammation in babesiosis triggers activation of ICAM-1 and the coagulation system. Twelve and 10 dogs with naturally occurring babesiosis before and after antiparasitic treatment, respectively, were compared with 10 healthy dogs. In this prospective study, diagnosis was made by blood smear examination and confirmed by PCR. C-reactive protein (CRP), soluble intercellular adhesion molecule 1 (sICAM-1), and von Willebrand factor (vWF) levels were measured by a canine ELISA kit, fibrinogen (FIB) and factor VIII activity levels were measured by coagulometric methods, and blood cell counts (WBC, RBC, PLT) were determined with an automatic analyzer. Compared to healthy dogs, the CRP, sICAM-1, and FIB concentrations were significantly increased before therapy and remained high for 3 days after therapy in dogs with babesiosis. vWF activity was significantly decreased in dogs with babesiosis before treatment. FVIII activity did not differ between dogs with babesiosis and healthy dogs. WBC; RBC and PLT were significantly lower before treatment and normalized by 3 days after treatment. A proinflammatory condition in babesiosis appears to influence endothelial dysfunction and hemostatic activity. Although clearly beneficial for the parasite, sequestered blood cells can obstruct blood flow in small vessels, promote an inflammatory state, and could increase the severity of babesiosis.

Prostaglandin E2‐induced intercellular adhesion molecule‐1 expression is mediated by cAMP/Epac signalling modules in bEnd.3 brain endothelial cells

Prostaglandin E₂ (PGE₂) has been implicated in the regulation of adhesion molecules, leukocyte adhesion and infiltration into inflamed site. However, the underlying mechanism therein involved remains ill-defined. In this study, we explored its cellular mechanism of action in the regulation of the intercellular adhesion molecule-1 (ICAM-1) expression in the brain endothelial cells. bEnd.3 cells, the murine cerebrovascular endothelial cell line and primary mouse brain endothelial cells were treated with PGE₂ with or without agonists/antagonists of PGE₂ receptors and associated signalling molecules. ICAM-1 expression, Akt phosphorylation and activity of NF-κB were determined by reverse transcription polymerase chain reaction (RT-PCR), immunoblot analysis, luciferase assay and immunocytochemistry. PGE₂ significantly up-regulated the expression of ICAM-1, which was blocked by EP4 antagonist (ONO-AE2-227) and knock-down of EP4. PGE₂ effects were mimicked by forskolin, dibutyryl cAMP (dbcAMP) and an exchange protein directly activated by cAMP (Epac) activator (8-Cpt-cAMP) but not a protein kinase A activator (N⁶-Bnz-cAMP). PGE₂-induced ICAM-1 expression was reduced by knock-down of Epac1. A PI3K specific inhibitor (LY294002), Akt inhibitor VIII (Akti) and NF-κB inhibitors (Bay-11-7082 and MG-132) attenuated the induction of ICAM-1 by PGE₂. PGE₂, dbcAMP and 8-Cpt-cAMP induced the phosphorylation of Akt, IκB kinase and IκBα and the translocation of p65 to the nucleus and increased NF-κB dependent reporter gene activity, which was diminished by Akti. Our findings suggest that PGE₂ induces ICAM-1 expression via EP4 receptor and Epac/Akt/NF-κB signalling pathway in bEnd.3 brain endothelial cells, supporting its pathophysiological role in brain inflammation.

Abstract 3792: WISP-1 increases cell migration and ICAM-1 expression in human oral squamous cell carcinomas.

Abstract Oral squamous cell carcinomas (OSCC) have a striking tendency to migration and metastasis to cervical lymph nodes. Wnt-1 induced secreted protein 1 (WISP-1) belongs to the CCN family (CTGF/CYR61/NOV), which is secreted cysteine-rich proteins. However, the effects of WISP-1 on migration and Intercellular adhesion molecule-1 (ICAM-1) expression in human OSCC are largely unknown. First, we found that the expression of WISP-1 in human OSCC tissues was higher than in normal oral tissues. We also demonstrated that WISP-1 enhanced cell migration and ICAM-1 up-regulation in human OSCC. Transfection of cells with ICAM-1 siRNA reduced WISP-1-mediated cell migration. WISP-1 activated αvβ3 integrin, ASK1, JNK/p38, c-Jun, and AP-1 signal transduction pathway, and WISP-1-induced expression of ICAM-1 and migration activity was inhibited by the αvβ3 antibody or inhibitor of ASK1, p38, JNK, and c-Jun. In addition, human OSCC were infected with lentivirus containing human WISP-1 shRNA which reduced the migratory ability and ICAM-1 expression. Over all, we characterized an important role for WISP-1 which regulates cell migratoin by increasing ICAM-1 expression in human OSCC via the αvβ3 integrin, ASK1, JNK/p38, c-Jun, and AP-1 signaling pathway. Citation Format: An-Chen Chang. WISP-1 increases cell migration and ICAM-1 expression in human oral squamous cell carcinomas. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3792. doi:10.1158/1538-7445.AM2013-3792