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C Saltini

Publications and source records attributed to C Saltini.

At least 73 records · Page 4Linked to original sources
PubMed1988

Does de novo immunoglobulin synthesis occur on the epithelial surface of the human lower respiratory tract?

Although synthesis of immunoglobulins by cells in the human lower respiratory tract has never been directly demonstrated, local production of immunoglobulins by cells within lung parenchyma is thought to play an important role in protecting the normal human lung against a variety of pathogenic organisms, and may contribute to the development of some interstitial lung diseases. To determine whether or not the epithelial surface of the human lower respiratory tract is a site of immunoglobulin synthesis, immunoglobulin production by cells recovered by bronchoalveolar lavage and lung parenchymal tissue from normal subjects and patients with idiopathic pulmonary fibrosis (IPF) or sarcoidosis was evaluated using a reverse hemolytic plaque assay and by measuring incorporation of [35S]methionine into immunoglobulins. Although the reverse hemolytic plaque assay demonstrated immunoglobin-releasing cells to be present on the surface of the lower respiratory tract of normal subjects, and present in increased numbers in patients with IPF or sarcoidosis, these plaque-forming cells were not actively synthesizing immunoglobulins, since preincubation of lavage cells in order to remove immunoglobulin bound to the surface of the cells reduced the number of plaque-forming cells, and inhibition of protein synthesis by cycloheximide did not further reduce the number of plaque-forming cells. Furthermore, direct evaluation of immunoglobulin synthesis using radiolabeling, immunoprecipitation and SDS-polyacrylamide gel electrophoresis failed to detect de novo IgG production by cells recovered from the alveolar surface of 15 of 17 subjects, IgM by 17 of 17, and IgA by 16 of 17.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Accumulation of Langerhans' cells on the epithelial surface of the lower respiratory tract in normal subjects in association with cigarette smoking.

Langerhans' cells are a defined subpopulation of the mononuclear phagocyte system known to accumulate in the lung in histiocytosis X, an interstitial lung disorder strongly linked to cigarette smoking. To evaluate the hypothesis that cigarette smoking itself may be associated with the accumulation of Langerhans' cells in the lung, normal nonsmokers (n = 5) and normal smokers (n = 10) were evaluated by bronchoalveolar lavage for the presence of Langerhans' cells as identified by the OKT6 monoclonal antibody and by transmission electron microscopy. While the OKT6 antibody identified 0.1 +/- 0.1% of the cells recovered from nonsmokers, it labeled 1.1 +/- 0.3% of those recovered from smokers (p less than 0.01). Furthermore, while electron microscopy demonstrated no Langerhans' cells among the lavage cells from nonsmokers, 0.4 +/- 0.1% of the cells recovered from normal smokers contained characteristic intracytoplasmic Birbeck granules, positively identifying them as Langerhans' cells. We conclude that cigarette smoking is associated with an expansion in the population of Langerhans' cells on the epithelial surface of the lower respiratory tract. While the mechanisms underlying this accumulation are unknown, it is possible that the properties of these cells contribute to the derangements of the pulmonary parenchyma found in cigarette smoking and establish a biologic link to the already observed epidemiologic association between histiocytosis X and cigarette smoking.

Adult↗
PubMed1988

Functional significance of anti-T-lymphocyte antibodies in sarcoidosis.

Pulmonary sarcoidosis is a chronic disorder characterized by the activation of helper/inducer T-cells in the lung without a concomitant increase in suppressor/cytotoxic T-cells. It is known that patients with sarcoidosis have circulating anti-T-cell antibodies, primarily of the IgM class. To evaluate a functional role for these antibodies in enhancing lung helper T-cell processes in pulmonary sarcoidosis, we evaluated serum and lavage fluid of patients with active sarcoidosis for the presence of anti-T-cell antibodies, the T-cell subset specificity of these antibodies, and the possible stimulatory or inhibitory effects of these antibodies on T-cells relevant to the exaggerated helper T-cell processes in sarcoidosis. Indirect immunofluorescence studies demonstrated that sarcoid patients had anti-T-cell antibodies of the IgM type reacting with autologous as well as with nonautologous normal T-cells. IgM recovered in sarcoid lavage fluid also reacted with T-cells, thus demonstrating the autoantibodies at the site of disease. Two-color immunofluorescence and flow cytometry showed that these sarcoid autoantibodies bound to mostly Leu2+ suppressor/cytotoxic T-cells, but also to a small proportion of Leu3+ helper/inducer T-cells. Incubating lymphocytes with sarcoid serum or IgM purified from sarcoid serum did not stimulate T-cell proliferation. Furthermore, when Leu2+ T-cells were stimulated with irradiated allogenic B-cells, increasing concentrations of sarcoid serum had no inhibitory effects on the activation and proliferative response of the Leu2+ T-cells. Likewise, the purified IgM anti-T-cell antibodies had no inhibitory effects on the mitogenic response of Leu2+ T-cells to the anti-T-cell antigen receptor-associated T3 complex antibody OKT3.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Evaluation of the in vitro and in vivo effects of cyclosporine on the lung T-lymphocyte alveolitis of active pulmonary sarcoidosis.

Pulmonary sarcoidosis is a granulomatous disorder characterized by the accumulation of activated helper/inducer T-lymphocytes in the lower respiratory tract, a process thought to be central to the pathogenesis of the disease. Because cyclosporine, a fungus-derived cyclic peptide, has specific inhibitory effects on T-lymphocyte activation, it should suppress activated sarcoid lung T-cells, and thus it should theoretically be an ideal therapeutic agent for sarcoidosis. This was confirmed in vitro: the addition of cyclosporine to T-cells recovered from the lungs of patients with active sarcoid suppressed the spontaneous release of interleukin-2 (IL-2) and monocyte chemotactic factor by these cells and inhibited their exaggerated spontaneous replication. In contrast, the oral administration of conventional doses (10 mg/kg/day) of cyclosporine to eight of these patients over a 6-month period was not accompanied by suppression of sarcoid lung T-cell activation. On the average, the spontaneous release of IL-2 and monocyte chemotactic factor, the proliferation of lymphocytes, and the number of helper/inducer T-cells present in the lungs of these subjects remained elevated and similar to their pretherapy values. Consistent with this lack of effect on sarcoid lung T-cell activation, no improvement in lung function was observed over the trial period. Thus, although cyclosporine is effective in vitro in suppressing the exaggerated activation of sarcoid lung T-cells, it does not do so in vivo, suggesting this agent will not be useful in the therapy of active pulmonary sarcoidosis, at least when administered in a conventional fashion.

Adult↗
PubMed1988

Spontaneous expression of the interleukin 2 receptor gene and presence of functional interleukin 2 receptors on T lymphocytes in the blood of individuals with active pulmonary sarcoidosis.

Current concepts of the pathogenesis of sarcoidosis suggest that the expanded numbers of activated T-helper/inducer cells at sites of disease activity result, at least in part, from their proliferation in the local milieu. Normal clonal proliferation of T cells involves activation and expression of the IL 2 receptor (IL 2R) gene. Thus, knowing that IL 2R mRNA transcripts are relatively long lived, we hypothesized that sarcoid blood T cells may contain IL 2R mRNA transcripts and express functional surface IL 2R, although the cells are probably activated elsewhere. Northern analysis using a 32P-labeled cDNA probe for the IL 2R p55 protein demonstrated that blood T cells of patients with active sarcoidosis, but not of normal patients, express 3.5- and 1.5-kb IL 2R mRNA transcripts, the same as those observed in normal T cells activated in vitro. Consistent with this, using flow cytometry and an MAb directed against the IL 2R p55 protein (2A3), we observed detectable levels of IL 2R surface protein on increased numbers of blood T cells of active sarcoidosis patients (4.7 +/- 0.9%) compared with blood T cells of normal patients (0.9 +/- 0.2%). Importantly, when the sarcoid blood T cells were exposed to IL 2 in vitro, they proliferated at a rate greater than that of normal blood T cells under the same conditions, suggesting that the IL 2R spontaneously expressed by sarcoid blood T cells were functionally active. In the context of the known compartmentalization of spontaneous IL 2 production and T cell proliferation at sites of disease in active pulmonary sarcoidosis, these IL 2R positive blood T cells would probably have a proliferative advantage if they trafficked to sites of active sarcoidosis, such as the lower respiratory tract.

Adult↗
PubMed1987

Corticosteroid therapy suppresses spontaneous interleukin 2 release and spontaneous proliferation of lung T lymphocytes of patients with active pulmonary sarcoidosis.

Active pulmonary sarcoidosis is characterized by the alveolar accumulation of activated helper T lymphocytes that are spontaneously releasing IL 2 and proliferating at an enhanced rate. In this regard, sarcoidosis represents a "model" human disorder to test in vivo the known in vitro action of corticosteroids on suppressing the activated IL 2 gene. Comparable groups of patients with active sarcoidosis were prospectively evaluated with no therapy or treated with corticosteroids. Over 3.2 +/- 0.4 mo, the untreated group had no significant change in spontaneous lung T cell release of IL 2 or spontaneous proliferation. In contrast, over the same period, the treated group had marked reduction of spontaneous lung T cell release of IL 2 and proliferation (p less than 0.01, all comparisons before therapy). Furthermore, Northern analysis of lung T cell RNA before therapy demonstrated IL 2 mRNA transcripts, whereas no IL 2 transcripts were observed during therapy. These observations are consistent with the concept that directly, or indirectly, corticosteroids are capable of suppressing the IL 2 gene in activated T lymphocytes in vivo.

Adrenal Cortex Hormones↗
PubMed1987

Evaluation of alveolar macrophages in normals and individuals with active pulmonary sarcoidosis for the spontaneous expression of the interleukin-1 beta gene.

We have evaluated the hypothesis that the presence of large numbers of activated helper/inducer T lymphocytes in the lungs of individuals with active pulmonary sarcoidosis is associated with the exaggerated release of interleukin-1 (IL-1) by alveolar macrophages. Evaluation of media from unstimulated cultured sarcoid alveolar macrophages failed to detect IL-1 activity. When parallel cultures of sarcoid and normal alveolar macrophages were stimulated with lipopolysaccharide (LPS), they released similar amounts of IL-1 activity. Using a highly specific polyclonal anti-IL-1 beta antibody and flow cytometry to evaluate cell-associated IL-1 beta, analysis of fresh alveolar macrophages from patients with active sarcoidosis and normal individuals revealed no detectable cell-associated IL-1 beta, but IL-1 beta was present when macrophages from sarcoid patients and normals were stimulated with LPS. Similar observations were made using immunoblot analysis of cell lysates of the same unstimulated and stimulated macrophages. Finally, Northern analysis of alveolar macrophages for IL-1 beta mRNA transcripts demonstrated minimal, but equivalent, amounts of IL-1 beta in both normal and sarcoid macrophages, as compared to the much larger quantities present in LPS-stimulated alveolar macrophages. Thus, while alveolar macrophages of individuals with sarcoidosis are clearly capable of expressing the IL-1 beta gene, these findings suggest that altered expression of the IL-1 beta gene by alveolar macrophages does not play a central role in the exaggerated lung T-cell activation characteristic of sarcoidosis.

Gene Expression Regulation↗
PubMed1987

Mechanisms of macrophage accumulation in the lungs of asbestos-exposed subjects.

Chronic asbestos exposure is associated with the accumulation of mononuclear phagocytes in the lower respiratory tract. This process can be both protective and injurious, since macrophages can aid in asbestos clearance yet also modulate structural derangements of the alveolar walls. To understand why macrophages accumulate in the lungs of asbestos-exposed persons, 2 possible mechanisms were evaluated using alveolar macrophages from subjects with histories of chronic high exposure to airborne asbestos: enhanced recruitment of blood monocytes to the lung, and an increased rate of replication of macrophages in situ. Monoclonal antibody analysis with antibodies that detect surface antigens on the majority of circulating blood monocytes but only on a minority of mature alveolar macrophages demonstrated that an increased proportion of alveolar macrophages of asbestos workers expressed monocyte lineage antigens, suggesting the presence of "young" newly recruited macrophages and thus enhanced recruitment. Culture of the alveolar macrophages from these subjects with [3H]thymidine followed by autoradiography demonstrated an increased proportion of alveolar macrophages synthesizing DNA, suggesting the macrophages are replicating at an increased rate in situ. These observations are consistent with the concept that both enhanced recruitment of blood monocytes and increased local proliferation of alveolar macrophages contribute to the accumulation mononuclear phagocytes in the lung of persons with chronic asbestos exposure.

Asbestos↗
PubMed1986

Compartmentalized activation of the interleukin 2 gene by lung T lymphocytes in active pulmonary sarcoidosis.

Sarcoidosis is a systemic disorder characterized by the accumulation of large numbers of interleukin 2 (IL 2) releasing helper (Leu-3+) T cells in involved organs. To determine whether the IL 2 gene is activated in sarcoidosis T cells in a systemic manner or only at sites of disease, cells obtained by bronchoalveolar lavage of individuals with active sarcoidosis, inactive sarcoidosis, and normals were evaluated for the spontaneous presence of IL 2 transcripts by using a human IL 2 cDNA probe and Northern analysis of extracted RNA. Freshly recovered lung cells of individuals with active pulmonary sarcoidosis contained 0.85 kilobase pairs (kb) IL 2 mRNA transcripts. In contrast, no IL 2 mRNA transcripts could be detected in fresh autologous blood T cells or in purified autologous blood Leu-3+ T cells, although IL 2 mRNA transcripts were inducible in these cells by phytohemaglutinin/phorbol myristic acetate. The sarcoid lung T cells, however, did not express the IL 2 gene constitutively; when placed in culture with no stimulation and evaluated after 24 hr, they demonstrated down regulation of the amounts of IL 2 mRNA transcripts, despite the fact that they were capable of re-expressing the IL 2 gene and releasing more IL 2 in response to added activation signals. Thus the activation of the IL 2 gene in T cells in active sarcoidosis occurs at the sites of disease and is not a generalized property of T cells throughout the body, and is not sustained if the T cells are removed from the sites of disease. Although the cause of sarcoid is unknown, these observations are consistent with the concept that sarcoid is associated with local stimuli at the site of disease eliciting the Leu-3+ T cell IL 2 gene activation that plays such a critical role in the pathogenesis of this disease.

Adult↗
PubMed1986

Spontaneous release of interleukin 2 by lung T lymphocytes in active pulmonary sarcoidosis is primarily from the Leu3+DR+ T cell subset.

The inflammation within the lower respiratory tract of individuals with pulmonary sarcoidosis is dominated by large numbers of helper T lymphocytes that proliferate and spontaneously release interleukin 2 (IL-2). To identify the lymphocyte subpopulation that releases IL-2 in this disorder, lung lymphocytes recovered by bronchoalveolar lavage were characterized using the monoclonal antibodies Leu4 (T lymphocyte), Leu3 (helper/inducer), Leu2 (suppressor/cytotoxic), and anti-HLA-DR, and separated by panning and flow cytometry. The majority of the IL-2 spontaneously released by T cells in the sarcoid lung was contributed by the Leu3+ cell population (Leu3+65 +/- 23 IL-2 units released/10(6) cells per 24 h; Leu2+ 9 +/- 8, P less than 0.04). Further characterization of the lung Leu3+ T cells in sarcoid demonstrated that 30 +/- 3% were expressing HLA-DR molecules on their surface compared with 6 +/- 1% in normals (P less than 0.01). Importantly, the subpopulation of Leu3+ lung T lymphocytes expressing a high intensity of HLA-DR molecules on their surface was responsible for the majority of the release of IL-2 in the sarcoid lung (Leu3+ high-intensity DR 42 +/- 17 U/10(6) cells per 24 h, Leu3+ low-intensity DR 8 +/- 1 U/10(6) cells per 24 h; P less than 0.01). Thus, the spontaneous release of IL-2 in the lung of sarcoid patients appears to be localized to a subset of Leu3+ high-intensity DR ("activated" lung helper/inducer) T lymphocytes. Because the sarcoid lung is characterized by markedly increased numbers of these cells, it is likely that this compartmentalized T cell population plays a major role in sustaining the exaggerated localized immune processes of this disorder.

Adult↗
PubMed1985

Enhanced alveolar macrophage-mediated antigen-induced T-lymphocyte proliferation in sarcoidosis.

Expansion of T-lymphocyte numbers is a characteristic feature of the alveolitis of pulmonary sarcoidosis. One mechanism that may influence the numbers of T-lymphocytes in the lung is the process of antigen presentation in which alveolar macrophages, in the presence of antigen, induce T-lymphocytes to replicate. To evaluate this process in sarcoidosis, alveolar macrophages were obtained by bronchoalveolar lavage, pulsed with tetanus toxoid, and co-cultured with purified autologous T cells. Strikingly, antigen-pulsed alveolar macrophages from sarcoid patients induced more than a twofold increase in autologous T-lymphocyte proliferation compared with the response seen using cells from normal or patients with idiopathic pulmonary fibrosis (P less than 0.001), all comparisons). In contrast, when monocytes were used as the antigen presenting cell, no significant differences were observed in T cell proliferation induced by antigen among the three groups. The enhanced T-lymphocyte proliferation induced by sarcoid alveolar macrophages was not dependent on the compartment from which the T cells were derived, and was independent of the specific antigen used. One possible explanation for augmented antigen presentation seen in sarcoid is that an increased percentage of sarcoid alveolar macrophages express HLA-DR or HLA-DS surface antigens. However, most normal and sarcoid alveolar macrophages express HLA-DR and HLA-DS surface antigens, and the percentage of macrophages expressing these antigens was not significantly different in the two groups. Thus, while the mechanisms of the enhanced antigen presentation in the sarcoid lung are unknown, the process of antigen-driven, alveolar macrophage-modulated lung T cell proliferation may explain, at least in part, the expansion of lung T-lymphocyte numbers that characterizes this disease.

Adolescent↗
PubMed1984

Chemiluminescence measurement of phagocytic activity of pulmonary macrophages in sarcoid alveolitis.

The phagocytic activity of alveolar macrophages in a group of patients with stage I and stage II fresh sarcoidosis has been studied in comparison with a group of healthy volunteers. The phagocytic activity has been measured by means of chemiluminescent emission recording. While no difference in the emission of chemiluminescence has been detected in polymorphonuclear leukocytes of patients and control subjects, a greater emission of chemiluminescence has been noted in the alveolar macrophages of sarcoid patients. Such a difference is statistically significant; its possible relation to alveolar inflammation has been considered.

Adult↗
PubMed1984

Diffuse interstitial lung diseases: a histochemical approach.

72 cases of diffuse interstitial lung diseases were observed from 1969 to 1976. Specimens removed from 47 patients were subjected to the whole spectrum of reactions. According to variation of both elastin and collagen, the following groups were outlined: group A: mycobacteriosis, farmer's lung, sarcoidosis and silicosis; group B: chronic eosinophilic pneumonia, lymphocytic interstitial pneumonia, post-tuberculous pulmonary fibrosis, and group C: X-ray pneumopathy, desquamative interstitial pneumonia, sclerodermic pneumopathy and chronic pulmonary fibrosis (primary chronic fibroadenomyosis). Each of these groups presents a close relationship between histochemical, radiological, clinical and functional findings.

Collagen↗
PubMed1984

Accurate quantification of cells recovered by bronchoalveolar lavage.

Quantification of the differential cell count and total number of cells recovered from the lower respiratory tract by bronchoalveolar lavage is a valuable technique for evaluating the alveolitis of patients with inflammatory disorders of the lower respiratory tract. The most commonly used technique for the evaluation of cells recovered by lavage has been to concentrate cells by centrifugation and then to determine total cell number using a hemocytometer and differential cell count from a Wright-Glemsa-stained cytocentrifuge preparation. However, we have noted that the percentage of small cells present in the original cell suspension recovered by lavage is greater than the percentage of lymphocytes identified on cytocentrifuge preparations. Therefore, we developed procedures for determining differential cell counts on lavage cells collected on Millipore filters and stained with hematoxylin-eosin (filter preparations) and compared the results of differential cell counts performed on filter preparations with those obtained using cytocentrifuge preparations. When cells recovered by lavage were collected on filter preparations, accurate differential cell counts were obtained, as confirmed by performing differential cell counts on cell mixtures of known composition, and by comparing differential cell counts obtained using filter preparations stained with hematoxylin-eosin with those obtained using filter preparations stained with a peroxidase cytochemical stain. The morphology of cells displayed on filter preparations was excellent, and interobserver variability in quantitating cell types recovered by lavage was less than 3%.(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchi↗
PubMed1977

Histological and histochemical pattern of phytohemagglutinin (PHA) skin test in patients with sarcoidosis.

Phytohemagglutinin (PHA) is a non-specific stimulant of blastogenic transformation and proliferation of T-lymphocytes in vitro. This material has been used for detection of a reduced lymphoblastic transformation in vitro and, as a skin test, for providing information in the evaluation of cellular immunodeficiency in man (BLAESE et al. 1973). As in sarcoidosis the immunological features are "depression of delayed-type hypersensitivity suggesting T-cell anergy and raised serum immunoglobulins suggesting B-cell overactivity", the authors used PHA skin test in comparison with patients with tuberculosis and M. Hodgkin. PHA positive reactions recorded at 72 hrs. were in 95% for sarcoidosis, 90% for tuberculosis and 5% for M. Hodgkin. But the histological and histochemical investigation of cutaneous biopsies demonstrated three significant differences at 72 hrs. in untreated patients with sarcoidosis compared to the material of tuberculosis patients: formation of lymphatic pseudo-follicles, an increased number of arteriovenous anastomoses and appearance of C-mucopolysaccharide (a histochemical marker of connective tissue in sarcoidosis). There were in sarcoidosis, unlike tuberculosis, blast cells, plasmocytes and a number of lymphocytes at 72 hrs. It is difficult for the authors to explain the different behaviour of the PHA skin test in sarcoidosis and tuberculosis. The appearance of the C-mucopolysaccharide might be a result of the raised serum level of IgM in patients with sarcoidosis.

Glycosaminoglycans↗