ICAM-1 Mice Research Articles

Ginsenoside Rg2 alleviates neurovascular damage in 3xTg-AD mice with Alzheimer's disease through the MAPK-ERK pathway

Alzheimer's disease (AD) is the most common form of dementia, and ginsenoside Rg2 (Rg2) is proven to inhibit AD’s progression. This study investigates the potential benefits of Rg2 treatment on 3xTg-AD mice. Following 6 weeks of gavage treatment, Rg2-treated 3xTg-AD mice exhibited improved spatial recognition memory behaviors, regional cerebral blood flow, and histopathological injury of the hippocampus, which were observed through a Y-maze test, laser Doppler flowmetry, and hematoxylin-eosin staining. Additionally, Rg2 treatment caused a decrease in the levels of amyloid beta 25–35, TNF-α, IL-1β, and IL-6, as measured by enzyme-linked immunosorbent assay, as well as a reduction in mRNA levels of IL-1β and IL-6 in 3xTg-AD mouse brains using quantitative real-time PCR. In particular, NeuN and CD31 levels were inhibited and GFAP level was elevated in 3xTg-AD mice that were observed through immunofluorescence, and these levels were all antagonized by Rg2, suggesting the effects of Rg2 on neurovascular damage, astrocyte activation, and neuronal loss. Furthermore, Western blot and qRT-PCR assays showed that Rg2 blocked the expression of ICAM-1 and VCAM-1 in 3xTg-AD mice. By Western blot, the ratios of p-ERK/ERK and p-MAPK/MAPK in 3xTg-AD mice were upregulated by Rg2 treatment, suggesting the neuroprotective effects of Rg2 may be related to the MAPK-ERK pathway. In summary, this study demonstrated the potential of Rg2 to improve AD and provided a scientific basis for research on the biological mechanism of AD and the development of Rg2.

Allogenic C57B/6->B6D2F1 Transplantation As a Model for Graft Versus Host Disease in the Brain

Bone marrow transplants are a common and reliable treatment for many disorders; however, in roughly 50% of patients, graft versus host disease (GvHD) occurs, causing significant morbidity and mortality. GvHD is an immune mediated disorder in which donor T cells recognize host antigens as foreign, causing donor T cells to proliferate and attack healthy host tissue. Though the pathogenesis of GvHD in organs such as the skin and colon has been well-documented, little is known about the effects of GvHD on the brain. Some clinical case studies have associated extensive neurological issues with onset of GvHD, with symptoms such as seizures, cognitive dysfunction, and cerebellar impairment including hemiparesis. Yet research involving the brain in GvHD lags behind research in other tissues. Our lab, working with a MHCII mismatched GvHD murine model, has studied GvHD in the brain in an effort to better understand the neurological effects of GvHD.It has been established that an increase in CD4+ and CD8+ T cells in GvHD causes much of the autoimmune reaction associated with the disease. Because of this, we sought to determine if these cell types infiltrate the brain, and if so, where. Using histochemical staining in a C57BL/6->B6D2F1 model (syngenically transplanted B6D2F1 mice were healthy controls), we saw significantly increased populations of CD3+ T cells (p<0.0001) in perivascular, periventricular, and meningeal locations. CD3+ cells are rarely observed in healthy mice and indicate an abnormal immune response in the brain. There was a significant increase in CD8+ (p=0.0316), but not in CD4+, cell counts in brains of GvHD mice as compared to brains of healthy control mice. These T cell populations were not found in parenchymal locations except proximal to micro vessels. The location of infiltrating T cells suggests that the epithelial cells lining neural blood vessels and the ependymal cells lining the ventricles are likely the target of inflammatory attack.Since an increase in CD8+ T cell populations suggests a pro-inflammatory Th1 immune response, we also investigated B226+ (B-cell) and IBA1+ (macrophage/microglia) cell populations in the brain. B-cells are associated with a Th2 response, while Th1 responses increase IBA1+ cell populations. We found no increase in numbers of B226+ cells in GvHD vs healthy mice, but found a significant increase in the number of IBA1+ cells (p<0.0001) in brains of GvHD mice, indicative of a Th1 immune response. Further, using a luminex multiplex assay, we found decreased serum levels of IL-4 (p = 0.0011) as well as increased levels of VEGF (p=0.0012) and ICAM-1 (p=0.0222) in GvHD mice as compared to healthy controls. The decreased level of IL-4 is consistent with the activation of a Th1 response and suppression of an anti-inflammatory Th2 response. The increase in ICAM-1, a molecule that regulates vascular permeability, indicates that GvHD induces increases in proteins important to vascular integrity, possibly allowing T cells to enter the brain via the blood brain barrier. Past studies have found increased levels of VEGF, and likewise of angiogenesis, in other organs affected by GVHD. Interestingly there is often a spike in VEGF-A levels following central nervous system injury, and the increase observed in our GvHD model may be a result of GvHD injury to the brain.Finally, since behavioral changes are often the first indicator of neurological involvement in GvHD, we wanted to assess whether our GvHD mouse model showed any notable changes in behavior. We found no motor deficits as measured through inverted grid and pole walk, nor did we see any difference in Morris Water Maze learning and recall between GvHD and control mice. However, we saw slower swimming speeds for GvHD mice (p<0.0001), correlating with signs of generalized somatic illness associated with GvHD, such as weight loss, signs of dehydration, and whisker barbering which may indicate stress. It is likely that the decrease in swimming speed is a result of generalized illness, rather than a neuromotor deficit caused by GvHD.In conclusion, our data suggest that the epithelial and ependymal cells surrounding the brain are a target of GvHD. Additionally, we found data supporting the theory that acute GvHD is associated with a Th1 response, as well as elevated serum ICAM-1 and VEGF levels. Our data indicate that GvHD may play a role in the brain of GvHD patients, an organ that has not previously been implicated in the pathology of GvHD. DisclosuresNo relevant conflicts of interest to declare.

5946The immune protein MD-2 is associated with early death in dilated cardiomyopathy and increases M1 macrophage polarization and recruitment in vitro

Abstract Objective Dilated cardiomyopathy (DCM) is characterized by systolic dysfunction and dilatation of ventricles. Myocardial inflammation and leukocyte activation and recruitment play a major role in the development and progression of disease. Myeloid differentiation factor-2 (MD-2) is the TLR (toll like receptor)-4 co-receptor and has been shown to be an important risk predictor for mortality of DCM patients. It is expressed in various cell types and mediates TLR-4 dependent inflammation/activation processes. Purpose We examined the impact of MD-2 on mortality of DCM patients and on polarization and recruitment of monocytes in vitro. Methods In 77 DCM patients, divided by median time point of death after first hospital admission into early and late death and alive group, MD-2 was quantified by means of ELISA. In THP-1 monocytes, cytokine secretion was quantified by ELISA after 72h treatment with MD-2 (5μg/mL). Bone marrow derived macrophages (BMDM) were generated from MD-2 KO and WT mice. NFkB phosphorylation (10min) and changes in gene expression (4h) of different adhesion molecules was quantified after treatment with 1 or 10ng/mL LPS. In human umbilical vein endothelial cells (HUVEC), protein kinase B (PKB) phosphorylation was quantified after 15min of treatment with 10ng/mL LPS or 5μg/mL MD-2. CCL2 gene expression in lysed cells (4h) and CCL2 secretion in supernatants (48h) were quantified to. Adhesion of monocytes on treated HUVEC was determined by FACS (Fig.1a). Initial HUVEC treatment with MD-2 (5μg/mL) or LPS (10 or 100ng/mL) took place for 48h. Results We found significant increased MD-2 in early (591.3ng/mL; N=18) vs late death (p=0.015) (369.2ng/mL; N=17) and alive (p≤0.0001) (303.2ng/mL; N=42) patients. Treatment of THP-1 cells (N=5) with MD-2 lead to a significantly increased secretion of inflammatory cytokines IL-8 (p=0.012), IP-10 (p=0.029), and MCP-1 (p=0.032) but not of anti-inflammatory cytokines IL-4, IL-10 and IL-13. Treatment of BMDM obtained from MD-2 KO and WT mice with 10ng/mL LPS lead to a increased phosphorylation of NFkB (N=4; p=0.022) and increased gene expression (N=6) of adhesion molecules VLA-4 (p=0.006) and ICAM-1 (p=0.049) in WT mice but not in KO mice. In HUVEC, LPS (p=0.008) and MD-2 induced a comparable increased phosphorylation of PKB (p=0.008) as well as an increase of CCL2 gene expression (p=0.029) and protein amount (p=0.039). Furthermore, treatment of HUVEC with both MD-2 (p=0.015) and LPS (p=0.0001) lead to a significant increase in monocyte adhesion (Fig.1). Conclusion The impact of MD-2 on cardiac inflammation and macrophage recruitment has not been described yet. In this study, we showed that, in DCM, elevated levels of sMD-2 are associated with early death. Furthermore, we could demonstrate that MD-2 enhances the process of HUVEC based monocyte recruitment. Finally, we could show that MD-2 induces inflammatory monocyte activity and triggers polarization of macrophages towards an inflammatory phenotype.

Mo1689 Nicotine Significantly Affects the Expression of Vascular Endothelial Adhesion Molecules and Ameliorates DSS Induced Colitis

Introduction Anti-adhesion molecule therapy is useful for inflammatory bowel diseases. Smoking has been reported to have a harmful effect on Crohn's disease, but it is still controversial in ulcerative colitis. Although effect of nicotine on adhesion molecules of cardiovascular system has been well recognized, it has not been studied in the intestine. We investigated effect of nicotine on murine colitis induced by dextran sodium sulfate (DSS) and compared expression of adhesion molecules in vitro in several conditions including preconditioning exposure. Involvement of nicotinic acetylcholine receptor (nAChR) was also examined. Method In in vivo study C57BL/6J mice were treated with 3% DSS and 0.1mg/ ml nicotine in drinking water for 7 days. Disease activity of colitis was assessed by DAI score. mRNA expressions of ICAM-1, VCAM-1 and MAdCAM-1 in colonic tissues were measured by qPCR. Microvascular endothelial cell line, bEnd3, was used for in vitro study. The cultured cells (2x105/ml) were treated with 5ng/ml TNF-α and 200μg/ml nicotine for 12 hours. mRNA expressions of ICAM-1, VCAM-1 and MAdCAM-1 in cells were measured by qPCR. Various concentrations of nicotine (0.01-1000μM) were tested. In pre-treatment protocol, cells were treated with nicotine for 3 days, and after 12 hours interval without nicotine, exposed to TNF-α and nicotine for 12 hours as treatment. In some experiments cells were cultured with TNF-α and nicotine under the presence of 0.01μM mecamylamine (Meca, nonselective nAChR antagonist) or 0.01μM methyllycaconitine (MLA, selective α7nAChR antagonist). Result In in vivo study, nicotine treatment decreased DAI score induced by DSS. Although nicotine alone did not affect expression of ICAM-1, VCAM-1 and MAdCAM-1 in control mice, addition of nicotine to DSS mice significantly attenuated the increased expression of VCAM-1 and MAdCAM-1 induced by DSS, and tended to inhibit ICAM-1. In in vitro study, expression of ICAM-1, VCAM-1 and MAdCAM-1 was increased by TNF-α. Increased expression of MAdCAM-1 was significantly attenuated by simultaneous administration of nicotine. In dose-response study, degree of ICAM-1 inhibition by nicotine was only observed at high doses, whereas that of MAdCAM-1 was observed in a low dose already. Interestingly pretreatment with nicotine before TNF-α decreased inhibitory effect of nicotine. These inhibitory effects tended to be attenuated by Meca or MLA, but not

Mo1690 Serotonin/5-HT3 Receptor and Substance P/NK1 Receptor Pathways Contribute to the Pathogenesis of Colonic Inflammation in Mice

Introduction Anti-adhesion molecule therapy is useful for inflammatory bowel diseases. Smoking has been reported to have a harmful effect on Crohn's disease, but it is still controversial in ulcerative colitis. Although effect of nicotine on adhesion molecules of cardiovascular system has been well recognized, it has not been studied in the intestine. We investigated effect of nicotine on murine colitis induced by dextran sodium sulfate (DSS) and compared expression of adhesion molecules in vitro in several conditions including preconditioning exposure. Involvement of nicotinic acetylcholine receptor (nAChR) was also examined. Method In in vivo study C57BL/6J mice were treated with 3% DSS and 0.1mg/ ml nicotine in drinking water for 7 days. Disease activity of colitis was assessed by DAI score. mRNA expressions of ICAM-1, VCAM-1 and MAdCAM-1 in colonic tissues were measured by qPCR. Microvascular endothelial cell line, bEnd3, was used for in vitro study. The cultured cells (2x105/ml) were treated with 5ng/ml TNF-α and 200μg/ml nicotine for 12 hours. mRNA expressions of ICAM-1, VCAM-1 and MAdCAM-1 in cells were measured by qPCR. Various concentrations of nicotine (0.01-1000μM) were tested. In pre-treatment protocol, cells were treated with nicotine for 3 days, and after 12 hours interval without nicotine, exposed to TNF-α and nicotine for 12 hours as treatment. In some experiments cells were cultured with TNF-α and nicotine under the presence of 0.01μM mecamylamine (Meca, nonselective nAChR antagonist) or 0.01μM methyllycaconitine (MLA, selective α7nAChR antagonist). Result In in vivo study, nicotine treatment decreased DAI score induced by DSS. Although nicotine alone did not affect expression of ICAM-1, VCAM-1 and MAdCAM-1 in control mice, addition of nicotine to DSS mice significantly attenuated the increased expression of VCAM-1 and MAdCAM-1 induced by DSS, and tended to inhibit ICAM-1. In in vitro study, expression of ICAM-1, VCAM-1 and MAdCAM-1 was increased by TNF-α. Increased expression of MAdCAM-1 was significantly attenuated by simultaneous administration of nicotine. In dose-response study, degree of ICAM-1 inhibition by nicotine was only observed at high doses, whereas that of MAdCAM-1 was observed in a low dose already. Interestingly pretreatment with nicotine before TNF-α decreased inhibitory effect of nicotine. These inhibitory effects tended to be attenuated by Meca or MLA, but not

An ethanol root extract of Cynanchum wilfordii containing acetophenones suppresses the expression of VCAM-1 and ICAM-1 in TNF-α-stimulated human aortic smooth muscle cells through the NF-κB pathway.

The root of Cynanchum wilfordii (C. wilfordii) contains several biologically active compounds which have been used as traditional medicines in Asia. In the present study, we evaluated the anti-inflammatory effects of an ethanol root extract of C. wilfordii (CWE) on tumor necrosis factor (TNF)-α-stimulated human aortic smooth muscle cells (HASMCs). The inhibitory effects of CWE on vascular cell adhesion molecule (VCAM)-1 expression under an optimum extraction condition were examined. CWE suppressed the expression of VCAM-1 and ICAM-1 and the adhesion of THP-1 monocytes to the TNF-α-stimulated HASMCs. Consistent with the in vitro observations, CWE inhibited the aortic expression of ICAM-1 and VCAM-1 in atherogenic diet-fed mice. CWE also downregulated the expression of nuclear factor-κB (NF-κB p65) and its uclear translocation in the stimulated HASMCs. In order to identify the active components in CWE, we re-extracted CWE using several solvents, and found that the ethyl acetate fraction was the most effective in suppressing the expression of VCAM-1 and ICAM-1. Four major acetophenones were purified from the ethyl acetate fraction, and two components, p-hydroxyacetophenone and cynandione A, potently inhibited the expression of ICAM-1 and VCAM-1 in the stimulated HASMCs. We assessed and determined the amounts of these two active components from CWE, and our results suggested that the root of C. wilfordii and its two bioactive acetophenones may be used for the prevention and treatment of atherosclerosis and vascular inflammatory diseases.

Abstract 1196: Vascular Endothelial Cells specific Endothelin-1 mediates Early Inflammation in Murine Model of Neointimal Formation

Complex mechanism of the chronic inflammatory process in vascular injury and atherosclerosis involves various types of cells and cytokines. Previous in vitro studies suggest that Endothelin-1 (ET-1) is produced by those cells, induces expression of several adhesion molecules and mediates the leukocyte-endothelial interaction. In the present study, we sought to determine whether local endothelial ET-1 plays a direct effect on early inflammation and neointimal formation as a response to vascular injury in vivo . Using Cre-loxP system and Tie-2 Cre promoter, Vascular Endothelial ET-1 Knockout (VEETKO) mice was generated. The mice showed 60% reduction of ET-1 mRNA level at major organs and undetected serum ET-1 level. To induce vascular inflammation, complete ligation of the left common carotid artery was performed in 12-weeks-old male VEETKO (n=35) and Wild Type (WT) littermates (n=34). Inhibition of vascular endothelial ET-1 prevented the 4-fold increase in ET-1 mRNA level of carotid artery after ligation, in contrast to that of WT mice. This prevention resulted in lower vascular inflammation revealed by lower mRNA and protein level of PECAM-1, ICAM-1, and MCP-1 in VEETKO mice. The lack of ET-1 in endothelium further inhibited the adhesion of inflammatory cells at early days after ligation as compared to that adhered in endothelium of WT mice (cell numbers, 20.7±4.9 vs. 54.6±3.9 respectively, p&lt;0.05, VEEETKO n=8/WT n=10). Observation at 4 weeks after ligation noted lower neointimal formation in VEETKO mice (n=11) as compared to WT littermates (n=12) (neointimal/medial ratio, 0.2±0.03 vs. 0.8±0.25 respectively, p&lt;0.05). Changes in carotid flow gave no hemodynamical effect as sistolic blood pressure maintained significantly lower in VEETKO mice as compared to WT mice (105.7±1.4 vs. 115.9±1.6 mmHg before ligation, p&lt;0.05 and 105.7±2.4 vs.119.08±1.08 mmHg after ligation, p&lt;0.05 n=20 each). In conclusion, these data demonstrated that lack of vascular endothelial ET-1 reduced inflammatory response of the vascular wall followed by inhibition of neointimal formation confirming the role of local endothelial ET-1 in mediating inflammation in vascular injury, in addition to its potent vasoconstrictor and proliferating effect.

Pitavastatin prevents NMDA‐induced retinal ganglion cell death by suppressing leukocyte recruitment

Excitotoxicity is a major cause of retinal ganglion cell (RGC) death during ischemic diseases such as vessel occlusion and diabetic retinopathy. However, the underlying mechanisms are not well understood. Statins, inhibitors of the HMG-CoA reductase, have neuroprotective effects in addition to their original role in lowering cholesterol. We hypothesize that pitavastatin, a recently introduced potent statin, is protective against N-methyl-d-aspartic acid (NMDA)-induced RGC death. Pitavastatin, administered by gavage, abolished NMDA-induced loss of RGCs. To elucidate the mechanisms underlying the neuroprotective effect of pitavastatin, we investigated its impact on inflammation. NMDA increased the expression of interleukin-1beta and TNF-alpha, and endothelial adhesion molecules, including ICAM-1, and induced leukocyte accumulation in the retinal vessels. Pitavastatin significantly reduced NMDA-induced leukocyte accumulation and up-regulation of endothelial adhesion molecules, whereas cytokine expression was unaffected. Systemic blockade of ICAM-1 in wild-type mice or absence of CD18 in gene-deficient (CD18(-/-)) mice significantly suppressed NMDA-induced leukocyte accumulation and RGC death. These findings suggest a novel and causative role for inflammatory leukocyte recruitment in NMDA-induced excitotoxicity. Furthermore, we show the novel neuroprotective effect of statins against excitotoxicity-induced RGC death. Statins or other anti-inflammatory agents may thus have therapeutic benefits in excitotoxicity-associated neuronal diseases through blockade of leukocyte recruitment.

4-1BB ligand enhances tumor-specific immunity of poxvirus vaccines

PurposeRecombinant poxvirus vaccines have been explored as tumor vaccines. The immunogenicity of these vaccines can be enhanced by co-expressing costimulatory molecules and tumor-associated antigens. While the B7–CD28 interaction has been most comprehensively investigated, other costimulatory molecules utilize different signaling pathways and might provide further cooperation in T cell priming and survival. 4-1BB (CD137) is a TNF family member and is critical for activation and long-term maintenance of primed T cells. This study was conducted to determine if a poxvirus expressing the ligand for 4-1BB (4-1BBL) could further improve the immune and therapeutic responses of a previously reported poxvirus vaccine expressing a triad of costimulatory molecules (B7.1, ICAM-1, and LFA-3). Experimental designA recombinant vaccinia virus expressing 4-1BBL was generated and characterized in an in vitro infection system. This vaccine was then used alone or in combination with a vaccinia virus expressing CEA, B7.1, ICAM-1, and LFA-3 in CEA-transgenic mice bearing established MC38 tumors. Tumor growth and immune responses against CEA and other tumor-associated antigens were determined. The level of anti-apoptotic proteins in responding T cells was determined by flow cytometry on tetramer selected T cells. ResultsThe combination of 4-1BBL with B7.1-based poxvirus vaccination resulted in significantly enhanced therapeutic effects against CEA-expressing tumors in a CEA-transgenic mouse model. This was associated with an increased level of CEA-specific CD4+ and CD8+ T cell responses, induction of antigen spreading to p53 and gp70, increased accumulation of CEA-specific T cells in the tumor microenvironment, and increased expression of bcl-XL and bcl-2 in CD4+ and CD8+ T cells in vaccinated mice. Conclusion4-1BBL cooperates with B7 in enhancing anti-tumor and immunologic responses in a recombinant poxvirus vaccine model. The inclusion of costimulatory molecules targeting distinct T cell signaling pathways provides a mechanism for enhancing the therapeutic effectiveness of tumor vaccines.

Assessment of the Effects of ISIS 2302, an Anti-Sense Inhibitor of Human ICAM-1, on Cellular and Humoral Immunity in Mice

ISIS 2302 is a phosphorothioate oligonucleotide designed to inhibit human ICAM-1 and is intended for treatment of inflammatory diseases. Molecules of this class are known to elicit pro-inflammatory effects, and immunotoxicity studies were performed in mice to elucidate the nature of effects of ISIS 2302 on mammalian immune function. ISIS 2302 (1, 5, 20, or 50 mg/kg/dose) was administered intravenously every other day for 27 days. The pro-inflammatory properties of the drug were observed at doses ≥ 20 mg/kg. A dose-dependent increase in spleen weight was associated with increased absolute splenocyte and B-lymphocyte counts after the 50 mg/kg/dose regimen. The mitogenic response of B-lymphocytes to bacterial lipopolysaccharide was increased after the 20 and 50 mg/kg/doses but antibody-forming cell activities remained unchanged. Total serum IgG concentration was decreased after the 20 and 50 mg/kg/dose regimens but IgM titers were unchanged. Increases in IL-6, IL-12, and MCP-1 as well as NK cell activity were observed after administration of 20 and 50 mg/kg/dose. Cytotoxic T-lymphocyte activity was decreased by the 50 mg/kg/dose regimen. Other changes in immune function were not observed in ISIS 2302-dosed mice. ISIS 3082, a murine active ICAM-1 inhibitor, was used to demonstrate the anti-inflammatory activity of ICAM-1 inhibition in the 2,4-dinitrofluorobenzene-induced contact sensitization model. Intravenous administration of 1 mg/kg of ISIS 3082 every other day for 27 days was unequivocally anti-inflammatory in the contact sensitization test. The results of these experiments support the conclusion that the prophlogistic effects of ISIS 2302 in mice are observed only at suprapharmacologic doses.

Involvement of ICAM-1 in the progression of atherosclerosis in APOE-knockout mice

Recent clinical evidence has indicated that the level of soluble ICAM-1 (sICAM-1) is correlated with the severity of atherosclerosis and can predict future cardiovascular events. Here, using apolipoprotein E (APOE)-deficient mice, we investigated the level of sICAM-1 in parallel with endothelial ICAM-1 expression and aortic atherosclerosis. We also examined the effect of ICAM-1 deficiency during the progression of atherosclerosis using double knockout mice. The level of sICAM-1 increased significantly in parallel with the progression of atherosclerosis in APOE-deficient mice, while the sICAM-1 level remained constant in wild-type mice from 3 to 10 months of age. ICAM-1 staining was detected in virtually all endothelial cells, however, ICAM-1 was expressed strongly in the endothelium overlying atheromatous palque in APOE-deficient mice. Deficiency of ICAM-1 in APOE-deficient mice significantly reduced lesions after 5 and 10 months. The present study supported the notion that the level of sICAM-1 is closely related with the severity of atherosclerosis and cardiovascular events, and also suggested that inhibition of ICAM-1 can delay the progression of atherosclerosis.

COX-2 protects gastric mucosa against ischemia-reperfusion injuries through down-regulation of the expression of ICAM-1 in mice

COX-2 protects gastric mucosa against ischemia-reperfusion injuries through down-regulation of the expression of ICAM-1 in mice

COX-2 protects gastric mucosa against ischemia-reperfusion injuries through down-regulation of the expression of ICAM-1 in mice

COX-2 protects gastric mucosa against ischemia-reperfusion injuries through down-regulation of the expression of ICAM-1 in mice

Expression of adhesion molecules relevant to leukocyte migration on the microvilli of liver peritoneal mesothelial cells.

To help assess the immunological functions of the liver peritoneum, expression and 3D-microlocalization of adhesion molecules were studied by immuno-SEM and -TEM. The peritoneal tissues of the liver obtained from lipopolysaccharide (LPS, 1.5 microg/g BW for 24 hr)-stimulated (n = 18 including nine controls) and non-stimulated mice (n = 6 including three controls) were analyzed by immunolabeling with 15 nm gold particle single-labeling analysis of ICAM-1, ICAM-2, VCAM-1, MAdCAM-1, PECAM-1, ELAM-1, and CD105 expression. In addition, 10 and 20 nm gold particle double-labeling analysis of ICAM-1 and VCAM-1 was carried out with conventional TEM and BSE (backscatter electron) imaging. Gold particles detected in the peritoneal mesothelial cells were quantified using a computer analyzer, LUZEX III. Only ICAM-1 in non-stimulated mice and both ICAM-1 and VCAM-1 in LPS-stimulated mice were expressed on the mesothelium, but no other adhesion molecules were detected in either condition. Expression of ICAM-1 was consistently about four times greater than that of VCAM-1. Each adhesion molecule was restricted to the microvilli. ICAM-1 was expressed on all microvilli and tended to form clusters of three or four molecules. On the other hand, about 24% of the microvilli expressed VCAM-1 and less clustering was seen. Double-labeling techniques disclosed that VCAM-1 and ICAM-1 were rarely closely associated, usually spaced by about 40 nm. These results suggest that microvilli of the mesothelial cell play a significant role in leukocyte migration in the peritoneal cavity, by providing the important substrates for adhesion, ICAM-1 and VCAM-1.

Expression of adhesion molecules relevant to leukocyte migration on the microvilli of liver peritoneal mesothelial cells

To help assess the immunological functions of the liver peritoneum, expression and 3D-microlocalization of adhesion molecules were studied by immuno-SEM and -TEM. The peritoneal tissues of the liver obtained from lipopolysaccharide (LPS, 1.5 microg/g BW for 24 hr)-stimulated (n = 18 including nine controls) and non-stimulated mice (n = 6 including three controls) were analyzed by immunolabeling with 15 nm gold particle single-labeling analysis of ICAM-1, ICAM-2, VCAM-1, MAdCAM-1, PECAM-1, ELAM-1, and CD105 expression. In addition, 10 and 20 nm gold particle double-labeling analysis of ICAM-1 and VCAM-1 was carried out with conventional TEM and BSE (backscatter electron) imaging. Gold particles detected in the peritoneal mesothelial cells were quantified using a computer analyzer, LUZEX III. Only ICAM-1 in non-stimulated mice and both ICAM-1 and VCAM-1 in LPS-stimulated mice were expressed on the mesothelium, but no other adhesion molecules were detected in either condition. Expression of ICAM-1 was consistently about four times greater than that of VCAM-1. Each adhesion molecule was restricted to the microvilli. ICAM-1 was expressed on all microvilli and tended to form clusters of three or four molecules. On the other hand, about 24% of the microvilli expressed VCAM-1 and less clustering was seen. Double-labeling techniques disclosed that VCAM-1 and ICAM-1 were rarely closely associated, usually spaced by about 40 nm. These results suggest that microvilli of the mesothelial cell play a significant role in leukocyte migration in the peritoneal cavity, by providing the important substrates for adhesion, ICAM-1 and VCAM-1.