No abstract

No abstract

Transforming growth factor-beta (TGF-beta) is a cytokine that promotes extracellular matrix accumulation and inhibits matrix degradation. Although the natural course of sarcoidosis is usually favourable, granuloma healing in the lung may result in pulmonary fibrosis and respiratory impairment in some patients. In this study TGF-beta1 was evaluated in bronchoalveolar lavage (BAL) fluid and culture supernatants of alveolar macrophages (AM) from 73 patients with biopsy-proven sarcoidosis. Disease activity was defined when patients recently developed or increased symptoms (cough, dyspnoea, systemic symptoms) and/or demonstrated increasing opacities on chest radiography. Pulmonary function tests were performed in all patients including forced expiratory volume in one second (FEV1), forced vital capacity (FVC), total lung capacity (TLC) and the diffusing capacity of the lung for carbon monoxide (DL,CO). Fourteen patients with idiopathic pulmonary fibrosis (IPF) and 14 healthy subjects were investigated as a control group. Immunohistochemistry was used to evaluate the cell distribution of TGF-beta1 on lung specimens. TGF-beta1 levels in BAL and in AM supernatants were not different between sarcoidosis and healthy subjects, whereas they were markedly increased in IPF. However, the TGF-beta1 level was significantly increased in BAL fluid but not in AM supernatants from sarcoidosis with altered lung function, compared with patients with normal lung function. The TGF-beta1 level in BAL was increased in active sarcoidosis but this increased level was mainly related to the higher level observed in patients with altered lung function. TGF-beta1 levels in BAL correlated significantly with the lymphocyte percentage. TGF-beta1 staining assessed by immunohistochemistry was intense in epithelioid histiocytes comprising non-necrotizing granuloma and in bronchiolar epithelial cells, in hyperplastic type II pneumocytes and occasionally in AM. This study supports the hypothesis that overproduction of transforming growth factor-beta1 is associated with functional impairment in patients with pulmonary sarcoidosis.

Allograft recipients undergoing cytomegalovirus infection present increased proportions of circulating CD8+ lymphocytes. A longitudinal study of 11 kidney and five liver allograft recipients with primary CMV infection but no other etiological factor of graft dysfunction revealed selective imbalances of peripheral blood CD8+ T cell subsets. Initially, CMV viraemia is associated with elevated CD8+bright T cell numbers and T cell activation. Activation markers fall to normal when viral cultures become negative (before the end of the first month). During the second to sixth month, most (12/16) patients keep up high CD8+ T cell counts (1050-2900 CD8+ cells/mm3), comprising an uncommon CD8+ T cell subset, as 45-73% of CD8+bright lymphocytes were CD3+ and TCR alpha beta+, but were not stained by anti-CD28, CD11b, CD16, CD56, and CD57 antibody. Unexpectedly, CD8+CD57+ T cells, a hallmark of CMV infection, do not appear until the second to sixth month of primary CMV infection, and their numbers increase progressively thereafter. They become the predominant CD8+ T cell subset after 6 months of infection and their persistence for several (up to 4) years is strongly correlated (r = 0.87) with expansion of CD8+ cells. By analysis with MoAbs, there was no bias towards the use of particular TCR-V beta gene families at any time of primary CMV infection. Persistence of CD8 lymphocytosis is thus directly related to the rate of expansion of an uncommon CD8+CD57- subset and its progressive replacement by CD8+CD57+ T cells that are chronically elicited by CMV.

Although respiratory involvement occurs in 50% of patients with relapsing polychondritis (RP) and augurs a poor prognosis, few previous studies have provided complete descriptions of respiratory tract involvement. For this reason, we investigated the respective role of clinical, functional, endoscopic, and radiographic (computed tomography [CT]) examinations in 9 consecutive patients with RP and lower respiratory tract localization. All exhibited cough, dyspnea, and wheezing. Eight had a nonreversible obstructive pattern with a marked decrease of the maximal flow ratio at 75% and 25% of vital capacity. Rotman functional criteria were evaluated to differentiate upper from lower respiratory tract involvement; they were consistent with the results of other examinations in 4/9 cases. Endoscopic examination showed moderate to severe inflammation in 8/9 patients; tracheal stenosis was present in 6/9 patients, bronchial stenosis in 4/9 patients, and tracheal collapse in 7 cases. CT showed tracheal stenosis in 8/9 patients (diffuse, 7; localized, 1) and bronchial stenosis in 6/9 patients. Tracheobronchial wall thickening and/or calcifications were observed in 7 cases. Clinical symptoms are of poor specificity for defining respiratory involvement precisely, although degree of dyspnea is correlated to the decrease in forced expiratory volume in 1 second (FEV1). Functional criteria were helpful in evaluating the obstructive ventilatory defect but did not differentiate, in most cases, the respective part of lower and upper respiratory involvement when using Rotman criteria. Compared to CT findings, endoscopic examination failed to identify tracheal and bronchial stenosis and tracheal wall alterations at an early stage of the disease. In our series CT appears to be a reliable method to identify tracheal and bronchial involvement and can be repeated safely during the course of the disease.