Nerve growth factor and neuropeptides circulating levels in systemic sclerosis (scleroderma).

OBJECTIVE: To determine the circulating levels of nerve growth factor (NGF), neuropeptide Y (NPY), and vasoactive intestinal peptide (VIP) in systemic sclerosis (SSc), and to correlate these levels with clinical and laboratory features. METHODS: Forty four patients with SSc were evaluated for circulating NGF (immunoenzymatic assay), NPY and VIP (radioimmunoassay), anticentromere and antitopoisomerase I autoantibodies, lung disease (pulmonary function tests with carbon monoxide transfer factor (TLCO), ventilation scintiscan with 99mTc DTPA radioaerosol, high resolution computed tomography (HRCT), pulmonary pressure (echo colour Doppler)), heart disease (standard and 24 ECG, echocardiography), cutaneous involvement (skin score), joint involvement (evidence of tender or swollen joints, or both), peripheral nervous system (PNS) involvement (electromyography), rheumatoid factor, angiotensin converting enzyme (fluorimetric method), von Willebrand factor (ELISA), and erythrocyte sedimentation rate (ESR) (Westergren). RESULTS: Circulating NGF levels in SSc were significantly increased compared with controls (p<0.00001) and significantly higher in the diffuse than in the limited subset of patients (p<0.01). Patients with articular disease had significantly higher levels of NGF. A significant indirect correlation between NGF levels and TLCO was detected (p<0.01), but no correlation was found between NGF and HRCT, DTPA, skin score, PNS involvement and angiotensin converting enzyme and von Willebrand factor levels, antitopoisomerase or anticentromere antibodies, and ESR. NGF levels increased progressively as the disease worsened. Similarly, VIP circulating levels were significantly increased in patients with SSc (p<0.001), whereas the increase of NPY levels did not reach statistical significance. However, both neuropeptides, following the same trend as NGF, increased as the disease worsened (skin score and lung disease). CONCLUSIONS: The increase of NGF and VIP in patients with SSc, the former in the diffuse subset of the disease, and in patients with prominent articular disease, may suggest a link between neurotransmitters and the disease pathogenesis. Neuropeptide circulating levels seem to increase only in patients with the most severe disease.

Circulating Vdelta1+ T cells are activated and accumulate in the skin of systemic sclerosis patients.

OBJECTIVE: An increased percentage of Vdelta1+/gamma/delta T cells has been detected both in the peripheral blood and bronchoalveolar lavage fluid of patients with systemic sclerosis (SSc). This study evaluated the subset distribution, activation status, and expression of cellular adhesion molecules, such as intercellular adhesion molecule 1 (CD54), very late activation antigen alpha4 (CD49d), and lymphocyte function-associated antigen 1alpha (CD11a), on circulating gamma/delta T cells, as well as their presence in the skin of SSc patients. METHODS: We studied 12 patients with SSc and 16 healthy volunteer donors. The distribution, activation status, and expression of cellular adhesion molecules were studied by flow cytometry; their presence in SSc patient skin was evaluated by immunohistochemistry. RESULTS: We found that the percentages and absolute numbers of peripheral blood gamma/delta T cells, CD16, CD8, CD45RO, CD25, HLA-DR, CD54, and CD11a coexpression did not differ significantly from those of the controls. CD49d gamma/delta T cells were significantly increased in SSc patients (2.3%) compared with controls (0.5%). A marked increase in the ratio of Vdelta1+ cells to gamma/delta cells was observed in the patients (72%) compared with the controls (31%). The Vdelta1+ subset showed a significant expression of both HLA-DR (83% of total Vdelta1+ cells) and CD49d (90% of total Vdelta1+ cells) compared with the controls (20.5% and 60%, respectively). In the skin, the absolute numbers of gamma/delta T cells were found in striking amounts in perivascular areas, particularly in the early edematous phase of SSc (22.58 in patients and 0 in controls); the majority of gamma/delta T cells were Vdelta1+ (19 in patients and 0 in controls). In the advanced phase of SSc, Vdelta1+ T cells were also increased compared with controls (3.5 versus 0). CONCLUSION: Our results show that Vdelta1+ T cells express both adhesion molecules and activation markers, and strongly support gamma/delta T cell homing to sites of inflammation. The increase in the Vdelta1 subset suggests a selective V gene subset expansion.

Treatment of psoriasis vulgaris with topical calcipotriol: is the clinical improvement of lesional skin related to a down-regulation of some cell adhesion molecules?

Calcipotriol is demonstrably efficacious for the treatment of psoriasis by virtue of its effects on the skin's immune system and on epidermal growth. We performed this study to emphasize the difference in the expression of certain cell adhesion molecules (CAMs) (ICAM-1, ELAM-1, LFA-1, VLA-3, VLA-6) in lesional and perilesional skin of 10 patients with psoriasis, before and after treatment with topical Calcipotriol. We took two biopsies of lesional and perilesional skin from each patient before and after treatment and then performed an immunohistochemical study to observe the expression of these CAMs, utilizing monoclonal antibodies against these adhesion molecules. We noticed reduced levels of infiltrating cells along with the expression of ICAM-1, LFA-1, ELAM-1 and of CAMs VLA-3, VLA-6 in basal and suprabasal keratinocytes. On the basis of these data we hypothesize that, besides epidermal keratinocytes, another target for Calcipotriol may be the skin's own immune system, suggesting that Calcipotriol can modify T lymphocyte activity (IL-1 dependent) through a down-regulation of CAMs.

Pachydermoperiostosis (primary hypertrophic osteoarthropathy): in vitro evidence for abnormal fibroblast proliferation.

Pachydermoperiostosis (PDP) is a disease characterized by the presence of pachydermia, periostosis and finger clubbing. Evidence that the skin and soft tissues are involved in the disease prompted the in vitro investigation of the behaviour of fibroblasts obtained from cutaneous biopsies of involved and apparently uninvolved PDP skin. PDP fibroblasts from affected skin demonstrated an abnormal proliferation, very rapid and tumultuous when compared to the growth of fibroblasts derived from apparently uninvolved skin and fibroblasts from the skin of healthy subjects. This characteristic was confirmed by the rate of thymidine incorporation, which was increased in PDP-affected fibroblasts (1152 dpm) compared to apparently non-PDP involved fibroblasts (273 dpm) and controls (262 dpm). Ultracentrifuged and non-centrifuged conditioned medium (CM) of fibroblasts affected or apparently not affected with PDP were used to evaluate the effect on the proliferation of healthy skin fibroblasts, compared to the effect of CM derived from healthy fibroblasts and from healthy fibroblasts incubated with 10% and 1% foetal calf serum. The CM of non-centrifuged PDP fibroblasts resulted in a statistically significant stimulation of fibroblast growth when compared to that expressed by ultracentrifuged PDP CM, healthy fibroblast CM and 10% stimulated CM. These data show that PDP fibroblasts maintain in vitro the capacity to proliferate at a higher rate than healthy fibroblasts and that in the CM residual cells and/or their debris may be present, inducing the abnormal growth of healthy fibroblasts. This evidence suggests that fibroblasts in PDP may play a role in the development of the disease.