Exogenous application of hydrogen sulfide donor attenuates inflammatory reactions through the L-selectin-involved pathway in the cutaneous reverse passive Arthus reaction.

H2S has been highlighted recently as an endogenous, gaseous signaling molecule, especially in inflammations. The deposition of IC induces an acute inflammatory response with tissue injury. To assess the roles of H2S in the IC-induced diseases, the cutaneous, reverse passive Arthus reaction was conducted using NaHS as a H2S donor. Furthermore, we conducted similar experiments using selectin(-/-) mice to determine the involvement of selectin molecules in the H2S-mediated pathway. Exogenous application of NaHS dramatically attenuated inflammatory reactions in WT mice associated with Arthus reaction. Namely, mRNA expressions of TNF-α, IFN-γ, and neutrophil numbers were reduced significantly in the lesional skins of NaHS-treated WT mice relative to untreated ones. NaHS treatment significantly reduced these three parameters in the lesional skins of E- and P-selectin(-/-) mice but not in those of L-selectin(-/-) mice. Quite similar results were obtained in the blocking study using WT mice injected with mAb to E-, P-, and L-selectin. Our results indicated that the exogenous application of NaHS attenuates inflammatory responses in reverse passive Arthus reaction through a L-selectin-involved pathway but not through E- or P-selectin pathways.

The roles of P- and E-selectins and P-selectin glycoprotein ligand-1 in primary and metastatic mouse melanomas.

BACKGROUND: Malignant melanoma is often accompanied by a host response of inflammatory cell infiltration that is highly regulated by multiple adhesion molecules. OBJECTIVE: To evaluate the role of adhesion molecules, including P-selectin glycoprotein ligand-1 (PSGL-1), P-selectin, and E-selectin. METHODS: Subcutaneous primary growth and metastasis to the lung of B16 melanoma cells were examined in mice lacking PSGL-1, P-selectin, or E-selectin. RESULTS: Primary subcutaneous growth of B16 melanoma was augmented by loss of PSGL-1, P-selectin, or E-selectin, while pulmonary metastasis was reduced by the loss of E-selectin. The enhancement of subcutaneous tumor growth was associated with a reduced accumulation of natural killer cells, CD4(+) T cells and CD8(+) T cells, while the attenuation of pulmonary metastasis was related to the numbers of CD8(+) T cells. The expressions of transforming growth factor (TGF)-ß and interleukin (IL)-6 were correlated with primary subcutaneous growth; TGF-ß, IL-6, and interferon-γ were related to number of metastatic lung nodules. Cytotoxicity against melanoma cells in splenocytes and in tumor-draining lymph node cells were not defective by the absence of adhesion molecules, suggesting that the enhancement of tumor growth and metastasis caused by the loss of selectins results from an impaired migration of effector cells into the tissue. CONCLUSIONS: The results indicate the complexity of anti-tumor responses mediated by adhesion molecules in primary subcutaneous tumors and pulmonary metastasis of murine experimental melanoma.

Clinical correlations with dermatomyositis-specific autoantibodies in adult Japanese patients with dermatomyositis: a multicenter cross-sectional study.

OBJECTIVE: To clarify the association of clinical and prognostic features with dermatomyositis (DM)-specific autoantibodies (Abs) in adult Japanese patients with DM. DESIGN: Retrospective study. SETTING: Kanazawa University Graduate School of Medical Science Department of Dermatology and collaborating medical centers. Patients A total of 376 consecutive adult Japanese patients with DM who visited our hospital or collaborating medical centers between 2003 and 2008. MAIN OUTCOME MEASURES: Clinical and laboratory characteristics of adult Japanese patients with DM and DM-specific Abs that include Abs against Mi-2, 155/140, and CADM-140. RESULTS: In patients with DM, anti-Mi-2, anti-155/140, and anti-CADM-140 were detected in 9 (2%), 25 (7%), and 43 (11%), respectively. These DM-specific Abs were mutually exclusive and were detected in none of 34 patients with polymyositis, 326 with systemic sclerosis, and 97 with systemic lupus erythematosus. Anti-Mi-2 was associated with classical DM without interstitial lung disease or malignancy, whereas anti-155/140 was associated with malignancy. Patients with anti-CADM-140 frequently had clinically amyopathic DM and rapidly progressive interstitial lung disease. Cumulative survival rates were more favorable in patients with anti-Mi-2 compared with those with anti-155/140 or anti-CADM-140 (P < .01 for both comparisons). Nearly all deaths occurred within 1 year after diagnosis in patients with anti-CADM-140. Conclusion Dermatomyositis-specific Abs define clinically distinct subsets and are useful for predicting clinical outcomes in patients with DM.

Autoantibody against survivin in patients with systemic sclerosis.

OBJECTIVE: In patients with systemic sclerosis (SSc), to determine concentrations of antibodies against survivin and their clinical association with SSc, and to evaluate serum survivin concentrations. METHODS: Anti-survivin antibody was examined by ELISA and immunoblotting using human recombinant survivin. Serum survivin levels were assessed by ELISA. RESULTS: IgG but not IgM anti-survivin antibody levels in patients with SSc were significantly higher than those in healthy controls and patients with systemic lupus erythematosus (SLE). When cutoff values were set as mean + 2 SD of control, IgG anti-survivin antibodies were positive in 41% (25/61) of patients with SSc, while they were detected in only 1 healthy individual (3%, 1/29) and 1 patient with SLE (5%, 1/20). Regarding the clinical correlation, patients with SSc who were positive for IgG anti-survivin antibody exhibited significantly longer disease duration than those who were negative. Immunoblotting analysis confirmed the presence of anti-survivin antibody in sera from patients with SSc. Serum survivin levels in patients with SSc were also significantly higher than in controls and patients with SLE. CONCLUSION: Our results suggest that autoantibody against survivin is generated in patients with SSc, especially those with long disease duration.

C-Mannosylated peptides derived from the thrombospondin type 1 repeat interact with Hsc70 to modulate its signaling in RAW264.7 cells.

The thrombospondin type 1 repeat (TSR) is a functional module of proteins called TSR superfamily proteins (e.g., thrombospondin, F-spondin, mindin, etc.) and includes a conserved Trp-x-x-Trp (W-x-x-W) motif, in which the first Trp residue is preferably modified by C-mannosylation. We previously reported that synthesized C-mannosylated TSR-derived peptides (e.g., C-Man-WSPW) specifically enhanced lipopolysaccharide-induced signaling in macrophage-like RAW264.7 cells. In this study, we searched for the proteins that bind to C-mannosylated TSR-derived peptides in RAW264.7 cells and identified heat shock cognate protein 70 (Hsc70). The binding affinity of Hsc70 for C-mannosylated peptides in solution was higher than that for the peptides without C-mannose. The binding was influenced by a nucleotide-induced conformational change of Hsc70, and C-mannosylated peptides preferred the substrate-binding domain of Hsc70. Furthermore, in RAW264.7 cells, addition of Hsc70 stimulated cellular signaling to produce tumor necrosis factor-alpha, via transforming growth factor-beta-activated kinase 1, and the Hsc70-induced signaling was enhanced more in the presence of the peptides with C-mannose than that without C-mannose, suggesting functional interaction between Hsc70 and the C-mannosylated peptides in the cells. Together, these results demonstrate a novel function of the C-mannosylation of TSR-derived peptides in terms of interaction with Hsc70 to regulate cellular signaling.

The proteasome inhibitor bortezomib inhibits T cell-dependent inflammatory responses.

CHS is a cutaneous, T cell-dependent, inflammatory reaction mediated mainly by antigen-specific effector T cells. Bortezomib is a proteasome inhibitor that has shown impressive efficacy for the treatment of multiple myeloma. In the current study, we have assessed the effect of bortezomib treatment of CHS in mice and found that bortezomib potently inhibited CHS responses. The attenuation of CHS responses was associated with decreased inflammatory cell infiltration in the challenged skin. Specifically, bortezomib-treated mice showed significantly decreased numbers of CD4(+) and CD8(+) T cells in the challenged skin and draining lymph nodes. Cytoplasmic IFN-gamma production by CD4(+) and CD8(+) T cells in the draining lymph nodes was decreased substantially by bortezomib treatment. Notably, bortezomib enhanced T cell apoptosis by inhibiting NF-kappaB activation during CHS responses. Thus, bortezomib treatment is likely to induce T cell death, thereby suppressing CHS responses by reducing IFN-gamma production. These findings suggest that bortezomib treatment could be a promising strategy for treating autoimmune and inflammatory disease.

Case of localized scleroderma associated with osteomyelitis.

We report a 4-year-old girl presenting with progressive linear scleroderma affecting the right leg. Biopsy specimen disclosed typical histopathological findings of localized scleroderma. Right leg magnetic resonance imaging (MRI) showed high signal areas on T(2)-weighted images on the subcutaneous fatty tissue, muscles and bone marrow, suggesting that skin inflammation extended to the bone marrow. Oral corticosteroid therapy was instituted with improvement of both skin sclerosis and MRI findings. Our observations suggest that MRI examination should be considered in patients with localized scleroderma to evaluate the extension of the inflammation.

Platelets control leukocyte recruitment in a murine model of cutaneous arthus reaction.

Platelets have been shown to be important in inflammation, but their role in the cutaneous Arthus reaction remains unclear. To assess the role of platelets in this pathogenetic process, the cutaneous Arthus reaction was examined in wild-type mice and mice lacking E-selectin, P-selectin, or P-selectin glycoprotein ligand-1 (PSGL-1) with or without platelet depletion by busulfan, a bone marrow precursor cell-specific toxin. Edema and hemorrhage induced by immune complex challenge significantly decreased in busulfan-treated wild-type mice compared with untreated mice. Busulfan treatment did not affect edema and hemorrhage in P-selectin- or PSGL-1-deficient mice, suggesting that the effect by busulfan is dependent on P-selectin and PSGL-1 expression. The inhibited edema and hemorrhage paralleled reduced infiltration of neutrophils and mast cells and reduced levels of circulating platelets. Increased cutaneous production of interleukin-6, tumor necrosis factor-alpha, and platelet-derived chemokines during Arthus reaction was inhibited in busulfan-treated wild-type mice relative to untreated mice, which paralleled the reduction in cutaneous inflammation. Flow cytometric analysis showed that immune complex challenge generated blood platelet-leukocyte aggregates that decreased by busulfan treatment. In thrombocytopenic mice, the cutaneous inflammation after immune complex challenge was restored by platelet infusion. These results suggest that platelets induce leukocyte recruitment into skin by forming platelet-leukocyte aggregates and secreting chemokines at inflamed sites, mainly through the interaction of P-selectin on platelets with PSGL-1 on leukocytes.

Autoantibody against one of the antioxidant repair enzymes, methionine sulfoxide reductase A, in systemic sclerosis: association with pulmonary fibrosis and vascular damage.

Systemic sclerosis (SSc) is a connective tissue disease characterized by fibrosis and vascular changes in the skin and internal organs with autoimmune background. It has been suggested that oxidative stress plays an important role in the development of SSc. To determine the prevalence and clinical correlation of autoantibody to methionine sulfoxide reductase A (MSRA), one of the antioxidant repair enzymes, in SSc, serum anti-MSRA autoantibody levels were examined in patients with SSc by enzyme-linked immunosorbent assay using recombinant MSRA. The presence of anti-MSRA antibody was evaluated by immunoblotting. To determine the functional relevance of anti-MSRA antibody in vivo, we assessed whether anti-MSRA antibody was able to inhibit MSRA enzymatic activity. Serum anti-MSRA antibody levels in SSc patients were significantly higher compared to controls and this autoantibody was detected in 33% of SSc patients. Serum anti-MSRA levels were significantly elevated in SSc patients with pulmonary fibrosis, cardiac involvement, or decreased total antioxidant power compared with those without them. Anti-MSRA antibodies also correlated positively with renal vascular damage determined as pulsatility index by color-flow Doppler ultrasonography of the renal interlobar arteries and negatively with pulmonary function tests. Furthermore, anti-MSRA antibody levels correlated positively with serum levels of 8-isoprostane and heat shock protein 70 that are markers of oxidative and cellular stresses. Remarkably, MSRA activity was inhibited by IgG isolated from SSc sera containing IgG anti-MSRA antibody. These results suggest that elevated anti-MSRA autoantibody is associated with the disease severity of SSc and may enhance the oxidative stress by inhibiting MSRA enzymatic activity.

Involvement of L-selectin in contact hypersensitivity responses augmented by auditory stress.

Stress affects the pathophysiology of cutaneous immune reactions, including contact hypersensitivity (CH) in individuals sensitized with sensitizing hapten, where local endothelial cell activation plays a critical role. To clarify the effects of stress in cutaneous immune reactions, we selected a CH model using annoying sound as a stress. Furthermore, we conducted the stress experiments by using selectin-deficient mice to determine the involvement of selectin molecules regarding local endothelial activation. Auditory stress augmented CH responses in the present study. Namely, ear thickness and mast cell numbers were significantly increased in stressed CH mice. mRNA expression of preprotachykinin-A, a precursor of substance-P; interferon-gamma; interleukin (IL)-4; IL-6; and tumor necrosis factor-alpha significantly increased in stressed CH mice. Furthermore, stressed L-selectin-deficient mice showed significant decreases in all parameters mentioned above relative to stressed wild-type mice in CH response. Meanwhile, treatment with anti-L-selectin Ab resulted in a significant decrease in ear thickness and mRNA levels of interferon-gamma, IL-4, IL-6, and tumor necrosis factor-alpha, but failed to significantly reduce preprotachykinin-A mRNA levels and mast cell numbers. Our results indicated that auditory stress enhances CH response and that the augmentation of this CH response might be mediated through L-selectin, but not through P- or E-selectin pathways.

Cytoprotective role of Phyllanthus urinaria L. and glutathione-S transferase Pi in doxorubicin-induced toxicity in H9c2 cells.

OBJECTIVE: To examine cytoprotective effect of Phyllanthus urinaria (PU) ethanolic extract in doxorubicin (DOX)-induced toxicity. The research focus was on the mechanism of action in association with the expression and localization of glutathione-S transferase (GST) in cardiac H9c2 cells. MATERIAL AND METHOD: The presence of GST isoforms was evaluated in H9c2 cells using western blot analysis and confocal immunofluorescence visualization. Cells were then treated with DOX in the presence and absence of PU and several cytoprotective indices were evaluated, including the expression of the rate-limiting enzyme for glutathione synthesis, gamma-glutamylcysteine synthetase (gamma-GCS), manganese superoxide dismutase (MnSOD), copper-zinc SOD (CuZnSOD), and GST activity from cell lysate. The investigations for GST-mediated cytoprotection from DOX-induced oxidative damage were further carried out by SiRNA transfection and apoptosis detection using TUNEL assay. RESULTS: GST Pi (GSTP) was predominantly expressed in H9c2 cells compared with GST Alpha and GST Mu. Treatment with PU protected against the cardiotoxicity of DOX by influencing the nuclear localization of GSTP without significantly affecting the enzymatic activity. Suppression of GSTP expression by RNA interference potentiated the accumulation of DOX in the nucleus and enhanced apoptosis as evaluated by TUNEL assay. Treatment with PU had a cytoprotective effect by reducing cellular levels of DOX with enhanced nuclear localization of GSTP in myocardiac cells. CONCLUSION: The cytoprotective mechanism of PU against DOX cardiotoxicity partially involved the presence of GSTP. Thus, PU extracts may be used as an alternative source of antioxidants with distinctive mechanisms of action that may be suitable for specific types of oxidative insults.

Elevated circulating TWEAK levels in systemic sclerosis: association with lower frequency of pulmonary fibrosis.

OBJECTIVE: To determine serum levels of tumor necrosis factor-related weak inducer of apoptosis (TWEAK) and its clinical associations in patients with systemic sclerosis (SSc). METHODS: Serum TWEAK levels from 70 patients with SSc were examined by ELISA. In a retrospective longitudinal study, sera from 23 patients with SSc were analyzed (followup 0.8-7.2 yrs). RESULTS: Serum TWEAK levels were elevated in patients with SSc (n = 70) compared with healthy controls (n = 31) and patients with systemic lupus erythematosus (n = 22). Among patients with SSc, there were no differences in serum TWEAK levels between limited cutaneous SSc and diffuse cutaneous SSc. Patients with SSc who had elevated TWEAK levels less often had pulmonary fibrosis and decreased vital capacity than those with normal TWEAK levels. In the longitudinal study, SSc patients with inactive pulmonary fibrosis or without pulmonary fibrosis consistently exhibited increased TWEAK levels, while those with active pulmonary fibrosis showed decreased TWEAK levels during the followup period. CONCLUSION: TWEAK levels were increased in patients with SSc, and associated with a lower frequency of pulmonary fibrosis in patients with SSc. TWEAK could be a protective factor against the development of pulmonary fibrosis in this disease and as such would be a possible therapeutic target.

P-selectin glycoprotein ligand-1 contributes to wound healing predominantly as a p-selectin ligand and partly as an e-selectin ligand.

Cell adhesion molecules are critical to wound healing through leukocyte recruitment. Although P-selectin glycoprotein ligand-1 (PSGL-1) regulates leukocyte rolling by binding P-selectin, but also binding E- and L-selectins with lower affinity, little is known about a role of PSGL-1 in wound healing. To clarify a role of PSGL-1 and its interaction with E- and P-selectins in wound healing, we investigated cutaneous wound healing in PSGL-1-deficient (PSGL-1(-/-)) mice in comparison with E-selectin(-/-), P-selectin(-/-), and P-selectin(-/-) mice treated with an anti-E-selectin antibody. PSGL-1 deficiency inhibited early wound healing, which was accompanied by decreased inflammatory cell infiltration and growth factor expression. By contrast, E-selectin deficiency did not affect wound healing. In general, the inhibitory effect of PSGL-1 deficiency on wound healing was similar to that of P-selectin deficiency either alone or with E-selectin blockade. However, early granulation tissue formation, late angiogenesis, and early infiltration of neutrophils and macrophages in PSGL-1(-/-) mice were inhibited beyond the inhibition in P-selectin(-/-) mice, but to a similar level of inhibition in P-selectin(-/-) mice with E-selectin blockade. These results suggest that PSGL-1 contributes to wound healing predominantly as a P-selectin ligand and partly as an E-selectin ligand by mediating infiltration of inflammatory cells.

Decreased levels of autoantibody against histone deacetylase 3 in patients with systemic sclerosis.

Systemic sclerosis (SSc) is characterized by immunological abnormalities, especially the production of autoantibodies against various cellular components. Treatment with histone deacetylase (HDAC) inhibitors prevents collagen accumulation in a mouse SSc model. Additionally, autoantibody against HDAC-3 is produced in colon cancer patients, while HDAC-1 and HDAC-2 do not elicit autoantibody response. To determine the presence and levels of antibodies (Abs) against HDAC-3 in SSc. Anti-HDAC-3 Ab was examined by enzyme-linked immunosorbent assay (ELISA) and immunoblotting using human recombinant HDAC-3. The HDAC-3 activity was evaluated by ELISA using the fluorimetric HDAC lysyl substrate that comprises an acetylated lysine side chain. Contrary to our hypothesis that autoimmune background in SSc induced the production of autoantibody against HDACs, IgG and IgM anti-HDAC-3 Ab levels in SSc patients were significantly lower than in normal controls (p < 0.0005 and 0.001, respectively). Furthermore, decreased levels of IgG anti-HDAC-3 Ab were specific to SSc, since IgG anti-HDAC-3 Ab levels in patients with dermatomyositis (DM) and those with systemic lupus erythematosus (SLE) were similar and slightly increased relative to normal controls, respectively. Immunoblotting analysis showed that anti-HDAC-3 Ab was detected in normal controls and patients with DM or SLE, while it was absent in SSc patients. The HDAC-3 activity was significantly inhibited by IgG isolated from sera of normal controls, whereas such inhibitory effect was not observed by IgG isolated from sera of SSc patients. These results indicate the lack of anti-HDAC-3 autoantibody in SSc patients, which is produced in healthy individuals as well as DM and SLE patients, suggesting that this autoantibody might function as protective Ab.

Anti-p53 autoantibody in systemic sclerosis: association with limited cutaneous systemic sclerosis.

OBJECTIVE: To determine the prevalence and clinical significance of anti-p53 antibody in patients with systemic sclerosis (SSc). METHODS: Anti-p53 antibody was examined by ELISA and immunoblotting. Findings were correlated with clinical features of disease and other autoantibodies and compared with other connective tissue diseases as well as normal controls. p53 activity to bind target DNA was evaluated by ELISA using a plate coated with oligonucleotide containing the consensus binding site for p53. RESULTS: IgG anti-p53 antibody levels were elevated in patients with SSc compared to patients with systemic lupus erythematosus (n = 20; p < 0.05), dermatomyositis (n = 21; p < 0.005), atopic dermatitis (n = 17; p < 0.0005), or bullous pemphigoid (n = 10; p < 0.0005) and normal controls (n = 21; p < 0.0005). Remarkably, anti-p53 antibody levels were higher in patients with limited cutaneous SSc (lSSc; n = 30) than those found in patients with diffuse cutaneous SSc (dSSc; n = 40; p < 0.05). IgG or IgM anti-p53 antibody levels did not correlate with the presence or levels of other autoantibodies. IgG anti-p53 antibody was associated with longer disease duration (p < 0.05) and decreased percentage vital capacity (p < 0.05), and correlated negatively with modified Rodnan total skin thickness score (r = -0.352, p < 0.01). Immunoblotting analysis confirmed the presence of IgG anti-p53 antibody in selected patients with SSc. IgG isolated from sera of selected patients with SSc that contained IgG anti-p53 antibody inhibited the p53 activity relative to normal controls. CONCLUSION: IgG anti-p53 antibody was detected in lSSc and dSSc, and was more prominent in lSSc, indicating that IgG anti-p53 antibody is a novel autoantibody associated with lSSc, a milder form of SSc.

C-Mannosylated peptides derived from the thrombospondin type 1 repeat enhance lipopolysaccharide-induced signaling in macrophage-like RAW264.7 cells.

C-Mannosylation is a unique type of glycosylation occurring at the first Trp (W) in the WXXW motif, which is found in the thrombospondin type 1 repeat (TSR) of proteins. However, the biological function of C-mannosylation is not fully understood. In this study, we investigated the effect of C-mannosylated TSR-derived peptides on lipopolysaccharide (LPS)-induced signaling in macrophage-like RAW264.7 cells. The cells were stimulated with LPS in the presence or absence of chemically synthesized peptides with or without C-mannose (e.g., (C-Man)-Trp-Ser-Pro-Trp [C-Man-WSPW], C-Man-W, WSPW, etc.), then the effects of the peptides on cellular viability and signaling were examined. We found a cytotoxic effect in the cells treated with LPS and C-Man-WSPW, but not in the cells solely treated with LPS or C-Man-WSPW. We also found that production of tumor necrosis factor-alpha (TNF-alpha) was upregulated more in response to LPS plus C-Man-WSPW, than in response to LPS plus WSPW or LPS alone. Among the LPS-induced signaling pathways that induce production of TNF-alpha, the activation of c-Jun N-terminal kinase (JNK) was greatly enhanced by LPS and C-Man-WSPW, and the production of TNF-alpha was suppressed by an inhibitor for JNK. Together, these results demonstrate a novel function of the C-mannosylated TSR-derived peptide motif, to promote LPS-induced JNK signaling, and this leads to an enhancement of cytotoxicity via the upregulation of TNF-alpha production.

Calreticulin represses E-cadherin gene expression in Madin-Darby canine kidney cells via Slug.

Calreticulin (CRT) is a multifunctional Ca(2+)-binding molecular chaperone in the endoplasmic reticulum. In mammals, the expression level of CRT differs markedly in a variety of organs and tissues, suggesting that CRT plays a specific role in each cell type. In the present study, we focused on CRT functions in the kidney, where overall expression of CRT is quite low, and established CRT-overexpressing kidney epithelial cell-derived Madin-Darby canine kidney cells by gene transfection. We demonstrated that, in CRT-overexpressing cells, the morphology was apparently changed, and the original polarized epithelial cell phenotype was destroyed. Furthermore, CRT-overexpressing cells showed enhanced migration through Matrigel-coated Boyden chamber wells, compared with controls. E-cadherin expression was significantly suppressed at the protein and transcriptional levels in CRT-overexpressing cells compared with controls. On the other hand, the expression of mesenchymal protein markers, such as N-cadherin and fibronectin, was up-regulated. We also found that the expression of Slug, a repressor of the E-cadherin promoter, was up-regulated by overexpression of CRT through altered Ca(2+) homeostasis, and this led to enhanced binding of Slug to the E-box element in the E-cadherin promoter. Thus, we conclude that CRT regulates the epithelial-mesenchymal transition-like change of cellular phenotype by modulating the Slug/E-cadherin pathway through altered Ca(2+) homeostasis in cells, suggesting a novel function of CRT in cell-cell interaction of epithelial cells.