Atsuyuki Igarashi

Clinical efficacy of basic fibroblast growth factor (bFGF) for diabetic ulcer

Basic fibroblast growth factor (bFGF) has been shown to promote wound healing. The present trial evaluated the clinical efficacy of bFGF for diabetic ulcer, a type of refractory skin ulcer, and the dose-response relationship. This was designed as a randomized, double-blind, dose-ranging, placebo-controlled trial. A total of 150 patients with non-ischaemic diabetic ulcers measuring 900 mm2 or less were randomized into a placebo group (n = 51), a 0.001% bFGF group (n = 49) and a 0.01% bFGF group (n = 50), and 148 of these patients received treatment for 8 weeks or less. The efficacy evaluation was carried out on 139 patients who met the protocol in this trial. The primary outcome was the percentage of patients showing 75% or greater reductions in the area of ulcer. The area of ulcer decreased by 75% or more in 57.5% (27/47), 72.3% (34/47), and 82.2% (37/45) in the placebo, 0.001% bFGF and 0.01% bFGF groups, respectively, and differences were significant between the 0.01% bFGF and placebo groups (p = 0.025). The cure rate was 46.8% (22/47), 57.4% (27/47), and 66.7% (30/45) in the placebo, 0.001% bFGF and 0.01% bFGF groups, respectively. The findings obtained in this trial showed wound healing accelerating effects of bFGF on diabetic ulcers.

Characterization of autoantibodies to endothelial cells in systemic sclerosis (SSc): association with pulmonary fibrosis

To determine the prevalence and the characterization of antibodies to endothelial cells in patients with SSc, serum samples from 80 patients with SSc, 20 patients with systemic lupus erythematosus (SLE), and 20 healthy control subjects were examined by ELISA using cultured human umbilical vein endothelial cells (HUVEC), indirect immunofluorescence analysis (IIF), and immunoblotting using cytoplasmic extract of HUVEC. IgG and/or IgM isotype anti‐endothelial cell antibodies (AECA) were demonstrated by ELISA in 43 of 80 patients with SSc (54%), in 15 of 20 patients with SLE (75%), and in none of 20 healthy control subjects. Immunofluorescence analysis on HUVEC substrate showed homogeneous cytoplasmic staining. Immunoblotting demonstrated that these patients had antibodies directed to one or several antigens of approximately 60, 90, 110 and 140u2003kD, and the most common responses were to the 90‐kD antigen. By the immunofluorescence method using HUVEC, affinity‐purified anti‐90‐kD antibodies showed identical cytoplasmic staining to that produced by sera positive for AECA. Furthermore, AECA were closely correlated with pulmonary fibrosis in patients with SSc. These findings suggest that patients with SSc have abnormal antibodies to endothelial cell antigens, and support the hypothesis that endothelial dysfunction is involved in the development of this disease.

Measurement of anticardiolipin antibodies by ELISA using β2-glycoprotein I (β2-GPI) in systemic sclerosis

In order to determine the prevalence and clinical significance of β2‐GPI‐dependent anticardiolipin antibodies (β2‐GPI/aCL) in patients with systemic sclerosis (SSc), serum samples from 80 patients with SSc, 20 patients with systemic lupus erythematosus (SLE), and 120 healthy control subjects were examined by ELISA using purified β2‐GPI. IgG isotype β2‐GPI/aCL was present in eight of 80 patients with SSc (10%), and the presence of β2‐GPI/aCL IgG was significantly correlated with the presence of isolated pulmonary hypertension (PH). Furthermore, levels of β2‐GPI/aCL IgG were significantly correlated with levels of mean pulmonary arterial pressure. These data suggest that IgG isotype β2‐GPI/aCL might be a serological indicator of the severity of PH in patients with SSc.

Increased levels of circulating intercellular adhesion molecule-1 in patients with localized scleroderma

BACKGROUNDnIntercellular adhesion molecule-1 (ICAM-1) is important in immune-mediated mechanisms, and its circulating form (cICAM-1) may be an indicator of immune activation. Localized scleroderma is accompanied by various immunologic abnormalities.nnnOBJECTIVEnWe investigated whether the serum level of cICAM-1 in patients with localized scleroderma was elevated and was correlated with the clinical or serologic features of this disease.nnnMETHODSnSerum cICAM-1 levels were determined by an enzyme-linked immunosorbent assay in 48 patients with localized scleroderma, in 20 patients with systemic sclerosis, and in 20 healthy control subjects.nnnRESULTSnSerum levels of cICAM-1 were significantly higher in patients with localized scleroderma than in the healthy control subjects. These levels correlated with the number of lesions, the number of involved areas, levels of antihistone antibody IgM, and levels of soluble interleukin 2 receptor.nnnCONCLUSIONnThe results suggest that immune activation may be a factor in localized scleroderma.

Coexistence of Morphea and Systemic Sclerosis

While the association of morphea and systemic sclerosis (SSc) is considered to be a rare condition, we observed well-demarcated sclerotic skin changes indistinguishable from morphea in 9 of 135 SSc patients who visited our clinic during the last decade. We consider this rate of incidence (6.7%) to be high enough to consider morphea to be one of the skin involvements of SSc. There was a significantly (p < 0.01) higher incidence of morphea in males (3 of 5) than in females (6 of 130). Only 3 of 111 SSc patients positive for antinuclear antibody (ANA) also showed morphea, whereas 6 of 9 patients negative for ANA showed morphea (p < 0.01). Although the mechanism underlying the development of morphea in SSc patients remains unknown, our observations suggest a heterogeneous pathogenesis related to SSc gender and ANA type.

Dipyridamole Specifically Decreases Platelet-Derived Growth Factor Release from Platelets

We previously reported that dipyridamole decreased platelet-derived growth factor (PDGF) levels in human serum by lowering the release of PDGF during blood clotting. In this study, we have shown that this effect is specific for dipyridamole, and is not shown in other anti-platelet drugs such as aspirin, trapidil or ticlopidine. In addition, dipyridamole has been shown to decrease the PDGF level selectively, but not the levels of other factors from alpha-granules in platelets (beta-thromboglobulin and platelet factor IV). These data indicate that dipyridamole may be an effective drug for preventing PDGF-related disorders.

Serum concentration of procollagen type I carboxyterminal propeptide in systemic sclerosis

The serum level of procollagen type I carboxyterminal propeptide (P1CP), which has been used as an index of collagen synthesis in patients with various fibrotic diseases during the active stage, was measured using enzyme-linked immunosorbent assay in 61 patients with systemic sclerosis (SSc) and in 21 control subjects. The mean P1CP level in the SSc patients was significantly higher than in the normal controls (mean ± SD, 326 ± 319 vs 128 ± 87 ng/ml; p<0.005). In 36% of the SSc patients, the serum P1CP level was significantly elevated more than two standard deviations above the mean control value. The mean serum P1CP level in patients with diffuse SSc was significantly higher than in those with limited SSc (411 ± 373 vs 255 ± 199 ng/ml; p<0.05). In addition, the SSc patients with elevated serum P1CP levels showed a significantly greater incidence of lung fibrosis and joint involvement than those with normal P1CP levels (p<0.005 and p<0.05, respectively). These results suggest that the serum P1CP level is a useful indicator of the severity of disease in SSc patients.

Response of scleroderma fibroblasts to various growth factors

SummaryAbnormal growth regulation in lesional skin fibroblasts may be related to scleroderma pathogenesis. We report on the abnormal response of cultured fibroblasts derived from sclerotic lesions to various growth factors. We investigated the responses of skin fibroblasts (10 strains) and normal fibroblasts (9 strains) to the growth factors as PDGF, TGF-Β1, EGF and basic FGF. Experiments were conducted during the proliferation and confluent stages. PDGF, EGF and basic FGF stimulated fibroblast growth during the proliferation and confluent stages, but the response of scleroderma fibroblasts was significantly lower than that of normal fibroblasts. TGF-Β1 slightly stimulated confluent fibroblast growth and inhibited proliferating fibroblasts, and the response of scleroderma fibroblasts exceeded that of normal fibroblasts. The decreased response to growth-stimulating factors observed in scleroderma fibroblasts suggests that cultured fibroblasts derived from scleroderma lesions were already senescent because they have been activated by growth-stimulating factors and repeatedly divided in vivo. Thus, abnormal growth regulation of skin fibroblasts may be partially related to the pathogenesis of scleroderma.

Dipyridamole specifically decreases platelet-derived growth factor release from platelets

The authors have previously reported that dipyridamole decreased platelet-derived growth factor levels in human serum by lowering the release of this factor during blood clotting. In the present study, we have shown that this effect is specific to dipyridamole, and does not occur with other antiplatelet drugs such as aspirin, trapidil or ticlopidine. In addition, dipyridamole has been shown to decrease the PDGF level selectively, but not the levels of other factors from alpha granules in platelets (beta-thromboglobulin and platelet factor 4). These data indicate that dipyridamole may be an effective drug for the prevention of PDGF-related disorders.

Longitudinal Study of Patients with Anticentromere Antibody

As has previously been reported by many investigators, the anticentromere antibody is considered to be a useful serologic marker for the CREST (calcinosis, Raynauds phenomenon, esophageal involvement, sclerodactyly and telangiectasia) variant of systemic sclerosis. However, this antibody also appears in other conditions. By screening antinuclear antibody tests using HEp-2 cells as substrate, 39 patients were shown to have the anticentromere antibody. These patients were divided into 4 groups: group 1 = 17 patients with systemic sclerosis; group 2 = 9 patients with Raynauds phenomenon alone; group 3 = 7 patients with other connective-tissue diseases, and group 4 = 6 patients with conditions other than those present in groups 1-3. Follow-up over years revealed that some patients suffering solely from Raynauds phenomenon (group 2) developed the symptoms of systemic sclerosis. In contrast, of the patients who did not have Raynauds phenomenon (group 4), none developed any symptom suggesting systemic sclerosis. We suggest that the simultaneous presence of Raynauds phenomenon and the anticentromere antibody predicts the occurrence of systemic sclerosis. In contrast, the presence of the anticentromere antibody alone cannot necessarily be used to predict the development of systemic sclerosis.