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A Chevailler

Publications and source records attributed to A Chevailler.

At least 19 recordsLinked to original sources
PubMed2005

[Antineutrophil cytoplasmic antibodies in cystic fibrosis. Frequency and significance].

UNLABELLED: Some immune system abnormalities have been reported in cystic fibrosis, particularly the presence of antineutrophil cytoplasmic antibodies (ANCAs). The purpose of this study was to determine the frequency of these antibodies in a population of patients with cystic fibrosis and to assess their relationship with the disease progression. POPULATION AND METHODS: This retrospective study looked for the presence of these antibodies in sera from 64 patients (30 boys and 34 girls) aged one to 29 years. All patients were followed up within the Cystic Fibrosis Center of the University Hospital of Angers. The serum samples were collected in 2001 during the yearly check-up to evaluate disease status. RESULTS: Seven of the 64 patients presented the antibodies. Univariate analysis showed that these patients were significantly older and more often chronically infected with Pseudomonas aeruginosa than the other patients. They also scored significantly more poorly on pulmonary radiography and showed significantly higher IgG and CRP. Multivariate analysis revealed that the two following independent factors were associated with the presence of ANCAs: chronic P. aeruginosa infection and high IgG level. CONCLUSION: This work confirms the abnormally high frequency of antineutrophil cytoplasmic antibodies in patients with cystic fibrosis. These antibodies were observed in the sickest patients with severe infection status. They reflect the impact of inflammatory processes in the pathogenesis of the disease. Detection of these antibodies might be an indication for intensified treatment of bronchial infections.

Adolescent↗
PubMed2005

Diagnostic value of anti-F-actin antibodies in a French multicenter study.

According to international criteria, autoimmune hepatitis (AIH) type 1 is characterized by the presence of antinuclear or anti-smooth muscle antibodies (SMA) with F-actin specificity. SMA have been found in 85% of AIH patients, but are not specific to this disease, and anti-F-actin specificity is not always verified when SMA are detected. The objective of this study was to determine the diagnostic value of anti-F-actin antibodies in a large population. A multicenter study involving 12 clinical centers was performed. Patients were selected on the basis of the presence of F-actin SMA detected by indirect immunofluorescence (IIF) on rat liver-kidney-stomach sections and was confirmed by IIF on Hep2 cells treated with colchicine, or F-actin dot-blot. The clinical status of patients was determined from their medical records. One hundred sixty-eight patients were included: 76% women, 24% men; mean age of 45 years (range, 2-88 years), with a bimodal age distribution. Sixty percent had AIH type 1, and 40% had another disease. In the group of women younger than 25 years, 90% had AIH type 1. Other pathologies associated with antiactin were other liver diseases (19%), including viral hepatitis C (7%), and non-liver diseases (21%), including connective tissue diseases (12%). Antibody titers were higher in AIH than in other diseases. Antiactin antibodies are of major diagnostic value in AIH, especially in young women; they may be found in other disease settings, but mostly at low levels.

Actins↗
PubMed2001

Lymphopenia in occupational pulmonary silicosis with or without autoimmune disease.

An increased prevalence of autoimmune diseases such as rheumatoid arthritis has been demonstrated in silica-exposed patients. The aim of this study was to determine the peripheral blood lymphocyte phenotype in a population of silicotic workers employed in the slate mines of the district. Silicosis was assessed in 58 patients according to the International Labor Office's criteria. Clinical and biological data including flow cytometric evaluation of the lymphocyte subsets were compared with those from 41 healthy volunteers. The silicotic patients had a higher prevalence of autoimmune diseases (6/58 versus 0/41: P < 0.05) and of elevated antinuclear antibody titres compared to the control group. A very significant decrease of total lymphocyte count (P < 0.001) involving B, T and Natural Killer cells was found in silicotic patients as compared with matched healthy volunteers. A significant increase in the percentage of activated T cells (12.3%) was observed in the silicotic group as compared to 6.5% in the control group (P = 5 x 10(-5)). Our results show that in silicotic patients, the absolute number of circulating lymphocytes is diminished with an increased proportion of activated T cells. Whether these findings could predispose to the development of autoimmune disorders is discussed.

Adult↗
PubMed2000

[Clinical significance of antiribosomal antibodies. Study Group on Autoimmunity (GEAI)].

PURPOSE: Autoantibodies directed against the ribosomal P proteins, P0, P1 and P2 (anti-P), have been related to lupus-related psychosis and/or depression. The diagnostic value of antibodies directed against other ribosomal proteins or 28S RNA (anti-no-P) remains unknown. A multicenter study including ten centers belonging to the study group for autoimmune diseases (GEAI) was conducted in order to determine the diagnostic value of anti-P and anti-no-P antibodies in a large population of patients. METHODS: The patients were selected on the basis of the presence of serum anti-ribosomal antibodies detected by indirect immunofluorescence (IF) on rat liver/kidney/stomach/pancreas sections and human HEp2 cells. The clinical course of all patients was studied using a predetermined survey. The specificity of anti-P antibodies were determined by Western blot. RESULTS: Anti-ribosomal antibodies were found in 82 patients. Fifty-five of them had systemic lupus erythematosus and 27 had another disease. Only 54% of the anti-ribosomal antibodies detected by IF were anti-P and were found in 69% of the patients with systemic lupus erythematosus. Anti-no-P antibodies (46%) were preferably detected in patients who suffered from another disease (78%). In patients with systemic lupus erythematosus, neurological and psychiatric disorders were more frequent in the no-P group (47% vs. 16%, P < 0.01) than arthritis, which was found more frequently in the P group (78% vs. 53%, P < 0.05). CONCLUSION: Anti P antibodies do not constitute a specific diagnostic marker of systemic lupus erythematosus, and lupus-related neuropsychiatric disorders would be preferably associated with the presence of anti no-P antibodies.

Animals↗
PubMed1998

The presence of cytoplasmic antineutrophil cytoplasmic antibodies (C-ANCA) in the course of subacute bacterial endocarditis with glomerular involvement, coincidence or association?

Antineutrophil cytoplasmic antibodies positivity with cytoplasmic pattern (C-ANCA) and proteinase-3 (PR-3) specificity was found in two patients with both subacute bacterial endocarditis (SBE) and glomerular involvement. Renal biopsy showed membranoproliferative glomerulonephritis in one case and focal segmental glomerulonephritis in the second case. Immunofluorescence study showed granular immune deposits in both cases evocating immune complex glomerulonephritis. Renal and biological manifestations disappeared with clinical improvement secondary to antibiotherapy. Physicians have to consider the possible occurrence of such C-PR-3 ANCA, claimed to be specific markers for Wegener's granulomatosis, in infectious diseases such as SBE. Hence we focus on the necessity of performing a renal biopsy with light microscopy and immunofluorescence studies in all patients with ANCA associated glomerular disease.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1997

Sialic acid-dependent recognition of laminin and fibrinogen by Aspergillus fumigatus conidia.

In an attempt to define the molecular basis of the adherence of Aspergillus fumigatus conidia to the host tissues, a step which might be mediated by the recognition of basement membrane laminin or fibrinogen, we analyzed the binding of these glycoproteins by flow cytometry and a microtiter plate adherence assay. Flow cytometry revealed that the binding of fluorescein isothiocyanate-labeled laminin to conidia was saturable and specific. Moreover, the ability of conidia to bind laminin increased with their maturation. Competition experiments showed a cross-reactivity between laminin and fibrinogen binding and a lack of interactions with glycosaminoglycans. In addition, the binding of laminin was not inhibited by the different adhesive synthetic peptides tested. Furthermore, the microtiter plate assay of adherence to chymotrypsin degradation products of laminin or fibrinogen purified by gel filtration suggested a unique binding site common to sequential degradation fragments or the presence of multiple binding sites on the two ligands. Therefore, the role of carbohydrates in the recognition process was investigated. Among the carbohydrates tested, constitutive of the conidial wall or of the oligosaccharide side chains of laminin and fibrinogen, only N-acetylneuraminic acid and sialyllactose inhibited the binding of these glycoproteins to conidia. In conclusion, these results strengthen the idea that the laminin and fibrinogen receptors in A. fumigatus are identical and suggest an interaction mediated by a sialic acid-specific lectin of the conidial wall.

Aspergillus fumigatus↗
PubMed1996

C-1-inhibitor binding monoclonal immunoglobins in three patients with acquired angioneurotic edema.

The syndrome of acquired angioneurotic edema (AAE) is characterized by the adult onset of angioedema, the lack of evidence for inheritance of the disorder, and the frequent association of the C1-inhibitor (C1-INH) deficiency with lymphoproliferative or other malignant diseases. Recently, a new type of AAE (type II AAE) has been described. The two major biologic differences of this new syndrome compared with all other previously reported AAE cases (type I AAE) are the presence in patients' sera of both anti-C1-INH autoantibodies, often monoclonal, and a circulating low molecular weight (95 kd) C1-INH protein. From the clinical point of view, the absence of underlying lymphoproliferative disease is the hallmark of type II AAE compared with type I AAE. However, the distinction between type I and type II AAE may not be so clear-cut. We report three patients with monoclonal gammopathies and AAE for whom the initial diagnosis was type I AAE. The demonstration by ELISA of the C1-INH binding ability of their monoclonal immunoglobulins in addition to the presence of 95 kd C1-INH protein enables us to change the diagnosis to type II AAE. From the therapeutic point of view, it is crucial to detect the anti-C1-INH antibody and to analyze the C1-INH size to distinguish type I and type II AAE, especially if patients have a monoclonal gammopathy, to give the appropriate treatment (attenuated androgens vs immunosuppressive regimen, respectively) to prevent a fatal outcome.

Aged↗
PubMed1996

Minocycline related lupus.

The determination of a factor triggering lupus-like symptoms could yield new insights into the management of rheumatic disease. We describe a case of minocycline related lupus in a young patient positive for HLA-DR2 who was prescribed minocycline 4 times for mild acne and developed rheumatic symptoms each time. We review 8 other cases.

Acne Vulgaris↗
PubMed1994

Golgi autoantibodies and autoantigens.

Autoantibodies directed against cellular constituents rarely react with antigens localized in the Golgi apparatus and little information is available regarding these particular antibodies. Although thousands of samples have been examined for autoantibodies in our laboratory on a routine basis, only three human sera with anti-Golgi antibodies could be studied. Using pre-embedding immunoelectron microscopy we have demonstrated that these sera have antibodies reacting with antigens located in the Golgi apparatus. The reaction product was exclusively located on cisternal and vesicular Golgi membranes. No intraluminal staining was seen and some saccules were negative. No specificity for a peculiar tissue or cell line was noted, suggesting that the targets or these autoantibodies are evolutionarily conserved. The F(ab')2 fragments retained full binding capacity in indirect immunofluorescence experiments, confirming true antibody activity. When tested by immunoblotting, the three sera reacted with different antigens with relative molecular weights of respectively 230, 150 and 80 kDa. The antigens recognized by anti-Golgi antibodies in two of the three sera were insensitive to trypsin degradation. Together, these results suggest that a set of different autoantigens are recognized by sera from various patients.

Animals↗
PubMed1994

[Autoantibodies against the Golgi apparatus].

Anti-Golgi autoantibodies were first reported 10 years ago. They are routinely detected by standard immunofluorescence whereas other methods such as immunoblotting or immunoelectron microscopy have provided some informations relating to the autoantigens that they recognize. From a clinical point of view, a distinction is appropriate between antibodies occurring at low titer in patients with some viral infections as well as in normal subjects, and antibodies of high titers found in association with autoimmune diseases such as Sjögren's syndrome or systemic lupus erythematosus. An associated liver dysfunction is also often noticed. Anti-Golgi autoantibodies are polyclonal and often mainly of the IgG isotype. In each case studied by immunoelectron microscopy, the recognized molecules were exclusively located on membranes of several cisternae. Although the real nature remains unknown, molecular weights of some autoantigens begin to be ascertained: bands of 230, 150 and 79 kDa have been revealed by different sera when tested by immunoblotting. Beside eventual implications in the field of pathogenesis, the study of this new kind of autoantibodies, based on the description of more sera and patients, might help to characterize some particular subsets of patients.

Animals↗
PubMed1994

Non-coordinated biosynthesis of early complement components in a deficiency of complement proteins C1r and C1s.

We report on a 60-year-old woman with systemic lupus erythematosus and a total (95%) C1r and a partial (36%) C1s deficiency. The patient complained about cutaneous lesions on forearms and legs without other systemic involvement. Elevated anti-nuclear, anti-native DNA and anti-SSA antibodies were present. The finding of persistently depressed levels of haemolytic complement activity (CH50) on both serum and plasma, associated with normal levels of C3, C4 and C2 components, and normal alternative pathway haemolytic activity showed a deficiency of an early component of the classical pathway. Indeed C1r component was below the limits of detection whereas C1s component was lowered (36%). The depressed CH50 was only corrected by purified C1r. Biosynthesis of C1r and C1s by patient's monocytes was spontaneously normal but not up-regulated by interferon-gamma for C1r alone, whereas the biosynthesis of C1s, but also of interleukin-6, was increased, indicating a specific disregulation of C1r. The deficiency was associated with a lupus syndrome and a fatal assumed septic shock. This is in agreement with other reported cases.

Cells, Cultured↗
PubMed1994

[Detection of anti-neutrophil cytoplasmic antibodies with proteinase 3 specificity by immunoblotting].

Antineutrophil cytoplasmic antibodies (ANCA) are autoantibodies mainly directed against alpha granules' components (especially proteinase 3 (PR 3) and myeloperoxidase (MPO). They are usually detected by indirect immunofluorescence (IIF) giving essentially two staining patterns, cytoplasmic and perinuclear. Nevertheless the IIF method does not allow to precise the true specificity of ANCA. From now on a better classification of systemic vasculitis requires such a determination. This can be done only by solid phase tests that require to be reliable, highly purified antigen, and, from a practical point of view, only a MPO-ELISA is currently available. We report on our experience with Western blot analysis of 67 IIF-ANCA positive sera. Using Western blot analysis to characterize ANCA specificity is not so easy as in the case of antibodies directed against extractable nuclear antigens: only PR 3 ANCA detection could be done reproducibly. PR 3 ANCA are mainly detected in the c-ACPN positive sera of patients with Wegener's granylomatosis. Nevertheless using both MPO-ELISA and PR 3 blot seems to increase the frequency of serum containing the two types of ANCA (anti PR 3 and anti MPO).

Autoantibodies↗
PubMed1993

Anti-myeloperoxidase antibodies and associated diseases.

Thirty five (41%) sera presented anti MPO specificity, 26 of them (74%) having a p-ANCA pattern. They were present in patients with vasculitis and isolated or predominant renal involvement, but also in 24% of Wegener patients.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1993

[Role of the titration of anti-neutrophil cytoplasmic antibodies in therapeutic follow-up of patients with systemic vasculitis].

We studied clinical and biological data of 18 patients presenting ANCA associated diseases for 16 months at least. Five relapses were preceded by ANCA elevation, 1 relapse was not. Four transient elevations were noted without any clinical event. We think ANCA level elevation by itself is not enough for deciding therapy intensification, clinical data are necessary for doing so.

Antibodies, Antineutrophil Cytoplasmic↗