Rice bodies in ischiogluteal bursitis.
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Publications and source records attributed to S Kon.
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Osteopontin (OPN) is a chemotactic protein that attracts immune cells, to inflammatory sites. The sensitization phase of allergic cutaneous contact hypersensitivity (CHS) requires the migration of Langerhans cells/dendritic cells (LCs/DCs) from skin to draining lymph nodes. Characterizing OPN function for LC/DC migration we found upregulated OPN expression in hapten sensitized skin and draining lymph nodes. OPN induces chemotactic LC/DC migration, initiates their emigration from the epidermis, and attracts LCs/DCs to draining lymph nodes by interacting with CD44 and alphav integrin. Furthermore, OPN-deficient mice have a significantly reduced CHS response that correlates with an impaired ability of OPN-deficient mice to attract LCs/DCs to draining lymph nodes. In conclusion, OPN is an important factor in the initiation of CHS by guiding LCs/DCs from skin into lymphatic organs.
Acute graft-versus-host diseases (GVHD) is a major cause of morbidity and mortality in patients undergoing allogeneic bone marrow transplantation (BMT). T helper 1 (Th1)-type cytokines such as interferon-gamma or tumor necrosis factor-alpha have been implicated in the pathogenesis of acute GVHD. TAK-603 is a new quinoline derivative, which is now in clinical trials for use as a disease-modifying antirheumatic drug. In preclinical studies, it inhibited delayed-type hypersensitivity, but not Arthus-type reaction, in mice, and selectively suppressed Th1 cytokine production. Thus, the present study was designed to investigate whether the Th1 inhibitor (TAK-603) ameliorates lethal acute GVHD in a mouse model. Administration of TAK-603 into BALB/c mice given 10 Gy total body irradiation followed by transplantation of bone marrow and spleen cells from C57BL/6 mice markedly reduced the mortality in association with minimal signs of GVHD pathology in the liver, intestine, and skin. TAK-603 reduced not only the production of Th1-type cytokines, but also the proportion of Th1 cells in CD4(+) helper T cells in this GVHD mouse model. These results suggest that TAK-603 could be a potent therapeutic agent for acute lethal GVHD.
Sarcoidosis is a systemic chronic granulomatous disease of unknown cause. Recent investigations revealed that the cytokine profile in inflamed lesions of sarcoidosis is Th1 dominant. To obtain better immunopathologic understanding of sarcoidosis, we examined the expression of IL-12 and IL-18 and their roles in IFN-gamma production in pulmonary sarcoidosis. Sarcoid cases had significantly elevated levels of IL-12 (p40 and p70) and IL-18 in bronchoalveolar lavage (BAL) fluids compared with healthy subjects. IL-12 p70 and IL-18 were immunohistochemically expressed in the epithelioid cells and giant cells of sarcoid granulomas. Significant induction of IFN-gamma, IL-12 p70, and IL-18 was observed from sarcoid BAL fluid cells with LPS stimulation, whereas LPS tended to induce only IL-12 p70 in BAL fluid cells from healthy subjects. Sarcoid cases had significantly greater IFN-gamma induction with LPS stimulation than healthy subjects did. IL-18 mRNA expression was observed in freshly isolated sarcoid BAL fluid cells as well as in LPS-stimulated sarcoid BAL fluid cells, but IFN-gamma and IL-12 mRNA expression was observed only in LPS-stimulated BAL fluid cells. Treatment with anti-IL-12- and anti-IL-18-neutralizing Abs significantly inhibited IFN-gamma production from LPS-stimulated BAL fluid cells of sarcoid cases. Coadministration of rIL-12 or rIL-18 induced greater IFN-gamma production in sarcoid BAL fluid cells than in normal BAL fluid cells. We concluded that bioactive IL-12 and IL-18 were produced in sarcoid BAL fluid cells and synergistically induced IFN-gamma production, indicating important cytokines in the Th1 response of sarcoidosis.
Osteopontin (OPN) is a secreted glycoprotein with cell adhesive and chemoattractive functions and is expressed in granulomas of sarcoidosis. It is well documented that full-length OPN (F-OPN) is susceptible to proteolytic fragmentation resulting in carboxyl-terminal OPN (C-OPN). We have previously revealed that C-OPN suppresses cell adhesion mediated by F-OPN. However, the implication of F-OPN and C-OPN in the progression of pulmonary involvement in sarcoidosis has not yet been elucidated. In this study, we demonstrated that (l) OPN was expressed in granulomas of sarcoidosis, (2) plasma F-OPN level in patients with sarcoidosis, especially in stage II patients, was significantly elevated compared with those of the controls, (3) plasma C-OPN levels in patients of stages 0, I, and III were significantly higher than those of the controls, and (4) in vitro recombinant F-OPN induces macrophage migration and that C-OPN inhibits cell migration mediated by F-OPN. These results suggest that F-OPN may promote granuloma formation in sarcoidosis, while C-OPN may suppress it. Thus, OPN and its fragment may play distinct roles in the development of sarcoidosis.
Osteopontin (OPN) is a phosphoprotein secreted by many cells of epithelial, mesenchymal, and hematopoietic origin. In the kidney, OPN is expressed in the renal tubules and collecting ducts and is excreted into the urine. A pathophysiologic role for urinary OPN has not been established. In this study, urinary excretion of OPN was analyzed in patients with primary glomerular diseases, including immunoglobulin A nephropathy (IgAN; n = 32), minimal change nephrotic syndrome (MCNS; n = 16), and membranous nephropathy (MN; n = 18). Compared with normal controls (n = 20), mean +/- SD of urinary OPN in IgAN patients was decreased significantly (21.4 +/- 6.2 versus 11.6 +/- 9.6 mg/g creatinine, P: < 0.001). In contrast, the levels of urinary OPN in patients with MCNS or MN did not differ significantly from normal values. Immunoblot analysis showed that OPN is present as a 55- to 60-kd molecule in normal urine. A 34-kd fragment of OPN was the major immunoreactive band in samples from IgAN patients. This fragment also was detectable in the urine from some patients with MCNS or MN but was absent in normal subjects. OPN has a thrombin-cleavage site near its central portion. Thrombin treatment of the urine from normal controls could result in 34-kd OPN fragments. Although the underlying mechanisms remain to be determined, these data provide evidence that secretion or processing (or both) of urinary OPN is altered in patients with IgAN.
Lymphoepithelioma-like carcinoma (LEC) of the colon is very rare. Here we report a case of LEC originating in the rectum that was closely associated with Epstein-Barr virus (EBV) infection. The histologic and immunohistologic features, namely, poorly differentiated adenocarcinoma with lymphoid stroma, showed this tumor to be an LEC. The EBV genome was detected by PCR using DNA obtained from tumor tissue sections. Immunohistochemically, EBV-determined nuclear antigen 2 was detected in the tumor cells, and in situ hybridization using EBV-encoded small RNAs probe showed positive labeling in some tumor cells together with a few stromal lymphoid cells. There are some reports of LEC cases that originated in the colon; however, a relation with EBV was not demonstrated. We report here a case of LEC of the rectum demonstrating a possible relation with EBV.
OBJECTIVE: To determine whether children with extended oligoarticular juvenile idiopathic arthritis (JIA) produce less of the anti-inflammatory cytokine interleukin-10 (IL-10) than those with persistent oligoarticular JIA. METHODS: We measured IL-10 production in the parents of children with oligoarticular or extended oligoarticular JIA, from whole-blood cultures stimulated with lipopolysaccharide. RESULTS: IL-10 production was lower in the parents of children with extended oligoarticular JIA compared with those of children with oligoarticular JIA (P=0.034). There was an increase in the percentage of ATA-containing genotypes (i.e. genotypes ATA/ATA, ATA/ACC or ATA/GCC) in the parents of children with extended oligoarticular JIA compared with healthy controls (P<0.02) but not in the parents of children with oligoarticular JIA. CONCLUSIONS: As approximately 84% of the variation in IL-10 production is thought to be genetically regulated, these results suggest that stimulated IL-10 production would be lower in children with extended oligoarticular JIA. Because IL-10 is an anti-inflammatory cytokine, this may partly explain why this group of children has more severe disease.
Pulmonary fibrosis is initiated by migration, adhesion, and proliferation of fibroblasts. Osteopontin (OPN) is one of the cytokines produced by activated macrophages and mediates various functions, including cell attachment and migration, by interacting with alphav integrin. In this study, we have investigated the role of OPN in the pathogenesis of pulmonary fibrosis. We developed a mouse model for pulmonary fibrosis by intratracheal instillation of bleomycin (BLM). OPN was strongly expressed in alveolar macrophages accumulating in the fibrotic area of the lung. OPN messenger RNA (mRNA) in the lung was notably induced by BLM instillation, and the development of the fibrotic process was associated with an increase in the expression of OPN mRNA and protein. In vitro, recombinant OPN enhanced migration, adhesion, and platelet-derived growth factor (PDGF)-mediated DNA synthesis of murine fibroblast cell line NIH3T3. These effects of OPN on fibroblasts were significantly suppressed by addition of antimouse alphav integrin monoclonal antibody (RMV-7). Furthermore, treatment of mice with RMV-7 repressed the extent of pulmonary fibrosis in this model. Conclusively, these data suggest that OPN produced by alveolar macrophages functions as a fibrogenic cytokine that promotes migration, adhesion, and proliferation of fibroblasts in the development of BLM-induced pulmonary fibrosis.
Osteopontin (OPN) has been shown to be expressed by cells in granulomas of various origins, but whether it plays a functional role in granuloma formation is not known. Here we used a cardiomyopathic hamster (TO2) model, to test the hypothesis that OPN contributes functionally to granuloma development. We immunized cardiomyopathic and normal hamsters by subcutaneous injection of bovine serum albumin in complete Freund's adjuvant, and assessed various tissues for both OPN RNA expression and granuloma formation. Cardiomyopathic hamsters expressed OPN, and formed granulomatous lesions, in heart tissue in both immunized and untreated animals. In addition, immunization induced expression of OPN in lung and lymph nodes of cardiomyopathic (but not normal) hamsters, and also induced granuloma formation in these organs. To test whether OPN expression could play a functional role in inducing granulomas, we produced an adenoviral vector containing the murine OPN gene, and introduced this vector intratracheally into the lungs of normal hamsters. The OPN-containing vector, but not the control vector, induced pulmonary granuloma formation. These studies provided direct in vivo evidence that OPN can contribute functionally to the formation of granulomatous lesions, and suggest that OPN expression may be a common factor involved in formation of granulomas of various origin.
We have previously reported that high glucose stimulates osteopontin (OPN) expression through protein kinase C-dependent pathways as well as hexosamine pathways in cultured rat aortic smooth muscle cells. The finding prompted us to study in vivo expression of OPN in diabetes mellitus. In the present study, we found by immunohistochemistry that medial layers of the carotid arteries of streptozotocin-induced diabetic rats and the forearm arteries of diabetic patients stained positively for OPN antibodies, whereas the staining from arteries of control rats and nondiabetic patients was negative. We also found that OPN stimulated the migration and enhanced platelet-derived growth factor (PDGF)-mediated DNA synthesis of cultured rat aortic smooth muscle cells. OPN and PDGF synergistically activated focal adhesion kinase as well as extracellular signal-regulated kinase; this finding seems to explain the OPN-induced enhancement of PDGF-mediated DNA synthesis. Taken together, our present results raise a possibility that OPN plays a role in the development of diabetic vascular complications.
We have generated synthetic peptides corresponding to various portions of human osteopontin (OPN) and have immunized rabbits and mice with these peptides to generate polyclonal and monoclonal antibodies specific to human OPN. We then generated six distinct sandwich enzyme-linked immunoabsorbent assay (ELISA) systems by using different pairs of polyclonal and monoclonal antibodies against human OPN. These systems allowed us to detect not only various isoforms and truncated forms of recombinant OPN, but also the glycosylated form of native urinary OPN. Most importantly, tumor-derived OPN was differentially detected by the six ELISA systems. The ELISA systems that we have developed will be useful for clarifying the functional roles for OPN in vivo in various physiologic and pathologic conditions.
BACKGROUND AND AIM OF THE WORK: Active sarcoidosis is considered to be a Th1 dominant condition. We examined whether Th1 cytokines are highly expressed at inflammed lesions of Japanese patients with sarcoidosis. METHODS: To investigate the mRNA expression of Th1 cytokines and IL-12 in sarcoid BAL cells, we used semiquantitative reverse transcription--polymerase chain reaction method. RESULTS: The mRNA expressions of Th1 cytokines (IFN-gamma and IL-2) in active sarcoid BAL cells were significantly elevated as compared with those in healthy volunteers. The proportion of positive IL-4 mRNA expression in sarcoid BAL cells was not significantly higher than that in healthy volunteers. Further, there was no significant difference in IFN-gamma mRNA levels between the groups positive and negative for IL-4 mRNA expression. Although the proportion of positive expression of IL-12 mRNA in active sarcoid BAL cells was not significantly higher than that in healthy volunteers, the group positive for IL-12 mRNA expression had significantly elevated levels of IFN-gamma mRNA than did the negative group. CONCLUSIONS: These results may indicate that IL-12 induces IFN-gamma expression and subsequent Th1 dominant condition in Japanese patients with sarcoidosis.
Tumor growth and metastasis are angiogenesis-dependent and tumor angiogenesis is a result of complex interplay of positive and negative regulators. Vascular endothelial growth factor (VEGF) occupies a particular place among the positive regulators of angiogenesis due to its potency and specificity for endothelial cells. VEGF upregulates several molecules such as growth factors, adhesion molecules, proteases, and protease receptors and it actually induces microvascular hyperpermeability, resulting in activation of thrombin from prothrombin. Osteopontin (OPN) is a secreted arginine-glycine-asparic acid (RGD)-containing phosphoprotein and it contains a predicted thrombin cleavage site. OPN binds to several integrins and CD44 variants. OPN has diverse functions such as cell adhesion, chemoattraction, and immunomodulation, and it induces endothelial cell migration and upregulates endothelial cell migration induced by VEGF. OPN expression is upregulated in human carcinomas. This review documents the functional roles of VEGF and OPN in angiogenesis and their clinical significance in tumor biology.
We present a rare case of diffuse large B-cell lymphoma transformed from immunoglobulin (Ig) A-secreting marginal zone B-cell lymphoma. A 62-year-old woman was admitted to our hospital for examination of a disseminated pulmonary shadow. Gradual swelling of bilateral axilla and right inguinal lymph nodes were noted after admission. Histological examination of the lymph node biopsy specimen revealed the appearance of marginal zone B-cell lymphoma. The surface Ig of lymphoma cells was IgA-kappa, which coincided with the class of monoclonal Ig found in the patient's serum. The lymph node swelling and pulmonary shadow subsided, and the serum IgA level was normalized by 3 courses of systemic chemotherapy. However, after 4 courses of treatment, new tumor lesions at the right chest wall and left arm progressively became apparent. The biopsy specimen of the tumor showed a feature of diffuse large B-cell lymphoma. Despite intensive chemotherapy, the patient died of spreading tumor burden into the central nervous system.
We immunized rats with recombinant murine osteopontin protein and obtained four monoclonal antibodies recognizing distinct epitopes of murine osteopontin. OPN1.2 recognized the amino-terminal half of OPN, while OPN2.2, OPN2.3, and OPN3.1 recognized the carboxy-terminal half of OPN. The epitope recognized by OPN2.2 was destroyed by further cleavage of the carboxy half of OPN. The epitope recognized by OPN2.3 was located in the amino-terminal end of the carboxy half of OPN, whereas that recognized by OPN3.1 was located in the carboxy-terminal end of the carboxy half of OPN. OPN1.2 and OPN2.2 recognized thrombin-cleaved osteopontin, whereas thrombin-cleaved osteopontin was not recognized by OPN2.3 and OPN3.1. Thus, these monoclonal antibodies will be useful in structure/function studies of the role of osteopontin in murine models of disease.
Osteopontin (OPN) is one of the most important components in calcium stone matrix, but its role in stone formation is not clear. Since quantitative data regarding the excretion of OPN are necessary to assess its role, we have developed a quantitative enzyme-linked immunosorbent assay (ELISA) for OPN, and measured the urinary OPN concentrations in urolithiasis patients. Forty-seven men with urinary stones composed chiefly of calcium oxalate participated in the study. The controls were 13 normal healthy male volunteers. Urine samples were collected early in the morning and analyzed by a quantitative ELISA employing purified polyclonal antibodies to synthesized OPN aminopolypeptides. The urinary ratio of the concentrations of OPN and creatinine (OPN/Cre) in the urolithiasis patients (0.039 +/- 0.029) was significantly lower than that in the control subjects (0.062 +/- 0.030) (P<0.05). Single stone formers (n = 26; 0.050 +/- 0.020) had significantly higher OPN/Cre ratios compared with recurrent stone formers (n = 21; 0.031 +/- 0.021) (P<0. 05). The results show that OPN excretion in urolithiasis patients was lowered, presumably because of the incorporation of OPN by kidney stones.
The present report describes a case of lymphoepithelioma-like carcinoma (LELC) of the lung and presents immunohistochemical and in situ hybridization (ISH) studies of the tumor. A 39-year-old Chinese woman, who was born in China and emigrated to Japan at the age of 29, suffered from a cough for 2 years and received a middle and lower lobectomy with mediastinal lymph node dissection after induction chemotherapy. The tumor consisted of undifferentiated carcinoma and areas of more differentiated squamous cell carcinoma with an intense lymphoid infiltrate. Serological studies and ISH studies showed EBV infection of the tumor. The immunophenotype of tumor-infiltrating T-lymphocytes (TITL) of the present case was examined immunohistochemically and was compared with that of an LELC case reported previously. Most CD3-positive T cells of TITL in both cases were labeled with both CD8 and TIA-1 but not with granzyme-B, indicating the TITL to be cytotoxic T lymphocytes (CTL) in the resting state. The lack of CTL activation at the tumor site might have been due to local inhibition of EBV-specific CTL responses such as T-cell anergy. Because the EBV-specific CTL derived from peripheral blood lymphocytes, in contrast to the TITL, may not be influenced by either tumor-produced suppressor factors or negative regulatory T cells, they may inhibit the hematogenous metastasis of EBV-positive LELC, possibly resulting in a better prognosis. Because LELC of the lung responded to preoperative chemotherapy in the present study, it may be useful for reducing the local tumor burden and facilitate subsequent local therapy, although the mechanism of chemosensitivity of LELC remains unknown.