Autoantibodies against matrix metalloproteinase-1 in patients with localized scleroderma

BACKGROUND: Localized scleroderma (LSc) is characterized by cutaneous fibrosis and various autoantibodies. OBJECTIVE: To determine the presence or levels of antibodies (Abs) against matrix metalloproteinase (MMP)-1 and their clinical relevance in LSc. METHODS: Anti-MMP-1 Ab was examined by ELISA (Enzyme-Linked ImmunoSorbent Assay) and immunoblotting using human recombinant MMP-1. MMP-1 collagenase activity was determined using biotinylated collagen as substrate and the amount of cleaved biotinylated fragments of collagen by MMP-1 was measured by ELISA. RESULTS: LSc patients exhibited significantly elevated IgG anti-MMP-1 Ab levels relative to normal controls at similar level of patients with systemic sclerosis (SSc). However, IgG anti-MMP-1 Ab levels were comparable among the 3 LSc subgroups: morphea, linear scleroderma, and generalized morphea. When absorbance values higher than the mean+2S.D. of normal controls were considered positive, IgG or IgM anti-MMP-1 Ab was found in 46% and 49% of total LSc patients and SSc patients, respectively. Anti-MMP-1 Ab was detected most frequently in morphea patients (60%), followed by linear scleroderma patients (47%) and then generalized morphea patients (25%). LSc patients positive for IgG anti-MMP-1 Ab had elevated levels of IgG anti-single-stranded DNA Ab, IgG anti-nucleosome Ab, and shorter disease duration relative to those negative. The presence of anti-MMP-1 Ab in LSc patients was confirmed by immunoblotting. IgG isolated from LSc patients' sera positive for IgG anti-MMP-1 Ab by ELISA inhibited MMP-1 collagenase activity. CONCLUSION: These results suggest that anti-MMP-1 autoantibody is a novel autoantibody in LSc.     

Anti-agalactosyl immunoglobulin G antibodies in localized scleroderma

BACKGROUND: Anti-agalactosyl immunoglobulin G (IgG) antibodies (anti-AG IgG) have been reported to be detected and correlated with disease activity in some collagen diseases. METHOD: Forty-seven serum samples from patients with localized scleroderma were examined using an enzyme-linked immunosorbent assay. RESULTS: Anti-AG IgG were positive in 19% of patients with localized scleroderma. The frequency of anti-AG IgG in generalized morphea was much higher than that in linear scleroderma or that in morphea. There was a significant correlation between anti-AG IgG levels and the number of the sclerotic lesions and between anti-AG IgG levels and the number of involved areas. The levels of anti-AG IgG were significantly higher in patients with antinuclear antibody, antisingle-stranded DNA antibody or rheumatoid factor than in those without. CONCLUSION: Anti-AG IgG can be an indicator of the severity of localized scleroderma.     

Radiation-induced localized scleroderma in breast cancer patients

Radiation-induced scleroderma in breast cancer patients appears to occur in approximately one out of every 500 patients. We report four cases that developed within 3 months of conservative breast surgery and postoperative radiation treatment. The reaction was contained entirely within the treatment field and demonstrated the typical features of this condition where the breast becomes erythematous, violaceous, indurated, retracted, and progressively pigmented. The breast tends to soften and become more comfortable over 1–4 years; however, significant induration, retraction and pigmentary changes remain. There appears to be no predictive factors. Radiation-induced scleroderma must be differentiated from cellulitis and recurrent breast cancer.     

Serum levels of manganese superoxide dismutase in patients with localized scleroderma

The objective was to determine the serum levels of manganese superoxide dismutase (Mn SOD) in patients with localized scleroderma and investigate their clinical significance in this disease. Serum samples from 15 patients with localized scleroderma and 20 healthy volunteers were examined by a specific enzyme-linked immunosorbent assay. Serum levels of Mn SOD were significantly higher in patients with generalized morphea than those in healthy individuals. And the patients with elevated serum Mn SOD levels had significantly larger number of sclerotic lesions and significantly higher serum levels of soluble interleukin-2 receptor than those without it. These results suggested that the serum levels of this enzyme may be a serological marker for the disease activity and the extent of skin involvement in this disease.     

Prevalence and characteristics of anti-single-stranded DNA antibodies in localized scleroderma. Comparison with systemic lupus erythematosus

Prevalence, levels, and immunoglobulin classes of anti-single-stranded DNA antibodies were determined by an enzyme-linked immunosorbent assay in 52 patients with localized scleroderma (33 with morphea, four with generalized morphea, and 15 with linear scleroderma), in 60 healthy controls, and, for comparison, in 31 patients with systemic lupus erythematosus. Localized scleroderma revealed a significant prevalence of anti-single-stranded DNA antibodies, mainly characterized by high levels and IgM and IgA isotypes. Comparison of antibody characteristics in different clinical forms of localized scleroderma showed some significant differences (levels and immunoglobulin isotypes). Comparison with systemic lupus erythematosus showed that frequency, high levels, and IgG isotype of anti-single-stranded DNA antibodies significantly prevailed in systemic lupus erythematosus, while the IgM isotype significantly prevailed in localized scleroderma. However, generalized morphea and linear scleroderma did not significantly differ from systemic lupus erythematosus as regards antibody frequency and prevalence of high antibody levels.     

Longitudinal melanonychia in localized scleroderma

Longitudinal melanonychia associated with scleroderma is rare. This is paradoxical, as increased skin pigmentation is frequent in the latter disease. This article reports 4 cases of longitudinal melanonychia that were found concurrently with various types of localized scleroderma. These 4 cases may be a coincidental finding despite the fact that pigmentation is so frequent a manifestation of scleroderma. In 2 cases, biopsy specimen of the nail matrix showed well-defined melanocytes without cellular atypia. This, in keeping with the pigmentation of scleroderma, appears to result from the functional activation of the matrix melanocytes.     

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 T₂-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.     

Novel autoantibody to Cu/Zn superoxide dismutase in patients with localized scleroderma

Abnormal production of reactive oxygen species (ROS) induces tissue damage and superoxide dismutase (SOD) that converts superoxide radicals to hydrogen peroxide functions as defense against ROS. Cu/Zn SOD administration has been shown to be effective for various fibrotic conditions by inhibiting the fibrogenic effects of ROS. We hypothesized that autoimmune background in localized scleroderma induced anti-Cu/Zn SOD autoantibodies that inhibited SOD activity and thereby contributed to fibrosis by increasing ROS. ELISA using human purified Cu/Zn SOD revealed that IgG or IgM anti-Cu/Zn SOD Ab was detected in the serum of 89% of localized scleroderma patients, especially 100% of patients with generalized morphea, the severest form of localized scleroderma, but was positive only in the serum of less than 15% of patients with other autoimmune disorders, including systemic sclerosis, systemic lupus erythematosus, dermatomyositis, and autoimmune bullous disorders. The immunoblotting analysis confirmed the presence of IgG anti-Cu/Zn SOD Ab in sera from localized scleroderma patients. Remarkably, anti-Cu/Zn SOD autoantibody could inhibit Cu/Zn SOD enzymatic activity. Collectively, these results indicate that anti-Cu/Zn SOD Ab is a novel, major autoantibody in localized scleroderma, and also suggest that the autoantibody may play a role in the development of fibrosis by directly inhibiting SOD activity.     

局限性硬皮病发病机制的研究进展

局限性硬皮病是一种以局部皮肤及皮下组织纤维化为特征的疾病.病因不明,发病机制可能涉及小血管的损伤、T细胞的活化以及结缔组织生成增加等多个过程.T细胞活化释放各种细胞因子,趋化因子,主要包括肿瘤坏死因子α、转化生长因子β、可溶性白细胞介素受体2和可溶性白细胞介素受体6等.血管内皮细胞的损伤也可介导纤维化相关的细胞因子释放.局限性硬皮病和系统性硬皮病在发病机制上有一定的区别和联系,概述局限性硬皮病发病机制的最新进展.     

Soluble CD4 and CD8 in serum from patients with localized scleroderma

Localized scleroderma has been shown to be accompanied by various immunologic abnormalities. To obtain functional information on activated CD4+ or CD8+ T cells, we studied the levels of soluble CD4 (sCD4) and soluble CD8 (sCD8) in serum from patients with localized scleroderma. Serum samples were examined by enzyme-linked immunosorbent assay. The samples were obtained from 49 patients in the following three subgroups: 15 patients with generalized morphea, 22 with linear scleroderma, and 12 with morphea. The levels of sCD4 and sCD8 were significantly elevated in patients with generalized morphea. Furthermore, these patients showed significantly higher levels of sCD4 than those with systemic sclerosis (SSc). The frequency of positivity for IgG anti-single-stranded DNA (ssDNA) antibody was significantly higher in localized scleroderma patients with elevated sCD4 levels than in patients with normal sCD4 levels. The frequency of positivity for antinuclear antibodies, IgM antihistone antibodies, IgG anti-ssDNA antibody and rheumatoid factor, and elevated sCD23 levels were significantly higher in localized scleroderma patients with elevated sCD8 levels than in patients with normal sCD8 levels. Our findings suggest that both CD4+ and CD8+ T cells are activated in vivo in generalized morphea and that the immunologic events in generalized morphea are different from those in SSc.