The Clinical Relevance of Antifibrillarin (anti-U3-RNP) Autoantibodies in Systemic Sclerosis.

Systemic sclerosis (SSc) is a heterogeneous autoimmune disease associated with several antinuclear autoantibodies useful to diagnosis and prognosis. The aim of the present multicentric study was to determine the clinical relevance of antifibrillarin autoantibodies (AFA) in patients with SSc. The clinical features of 37 patients with SSc positive for AFA (AFA+) and 139 SSc patients without AFA (AFA-) were collected retrospectively from medical records to enable a comparison between AFA- and AFA+ patients. Antifibrillarin autoantibodies were screened by an indirect immunofluorescence technique using HEp2 cells and identified by an in-house Western blot technique and/or an EliA test. Comparing AFA+ and AFA- patients, AFA+ patients were significantly younger at disease onset (36.9 versus 42.9; P = 0.02), more frequently male (P = 0.02) and of Afro-Caribbean descent (65% versus 7.7%; P < 0.001). At diagnosis, the Rodnan skin score evaluating the cutaneous manifestations was higher (13.3 versus 8.7; P = 0.01) and myositis was also more common in the AFA+ group (31.4% versus 12.2%; P < 0.01). Patients with AFA+ were not associated with diffuse cutaneous SSc or with lung involvement and no difference in survival was observed. Antifibrillarin autoantibodies are associated with patients of Afro-Caribbean origin and can identify patients with SSc who are younger at disease onset and display a higher prevalence of myositis.

Update on Anti-Saccharomyces cerevisiae antibodies, anti-nuclear associated anti-neutrophil antibodies and antibodies to exocrine pancreas detected by indirect immunofluorescence as biomarkers in chronic inflammatory bowel diseases: results of a multicenter study.

AIM: Anti-Saccharomyces cerevisiae antibodies (ASCA), anti-nuclear associated anti-neutrophil antibodies (NANA) and antibodies to exocrine pancreas (PAB), are serological tools for discriminating Crohn's disease (CrD) and ulcerative colitis (UC). Like CrD, coeliac disease (CoD) is an inflammatory bowel disease (IBD) associated with (auto) antibodies. Performing a multicenter study we primarily aimed to determine the performance of ASCA, NANA and PAB tests for IBD diagnosis in children and adults, and secondarily to evaluate the prevalence of these markers in CoD. METHODS: Sera of 109 patients with CrD, 78 with UC, 45 with CoD and 50 healthy blood donors were retrospectively included. ASCA, NANA and PAB were detected by indirect immunofluorescence (IIF). RESULTS: ASCA+/NANA- profile displayed a positive predictive value of 94.2% for CrD. Detection of ASCA was correlated with a more severe clinical profile of CrD and treatment of the disease did not influence their serum levels. ASCA positivity was found in 37.9% of active CoD. PAB were found in 36.7% CrD and 13.3% CoD patients and were not correlated with clinical features of CrD, except with an early onset of the disease. Fifteen CrD patients were ASCA negative and PAB positive. CONCLUSION: ASCA and PAB detected by IIF are specific markers for CrD although their presence does not rule out a possible active CoD. The combination of ASCA, NANA and PAB tests improves the sensitivity of immunological markers for CrD. Repeating ASCA, NANA, and PAB testing during the course of CrD has no clinical value.

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.

[Analytic study of dot blotting for the detection of anti-Jo-1, anti-M2, anti-ribosomes and anti-LKM]. / Etude analytique d'un dot blot pour la détection des auto-anticorps anti-Jo-1, anti-M2, anti-ribosomes et anti-LKM1.

The Cyto-Dot 4 HM043 kit commercialised by BMD, has replaced the Cyto-Dot HM010 kit that allowed three auto-antibodies detection (anti-Jo-1, anti-M2 and anti-ribosomal protein). Detection of anti-LKM1 auto-antibody was added. These four auto-antibodies have in common only the intracytoplasmic localisation of their respective antigen. The aim of our study was to evaluate this new kit using 104 sera and to compare our results with reference techniques (indirect immunofluorescence IF for anti-M2, anti-ribosomal protein and anti-LKM1, double immunodiffusion ID for anti-Jo-1 and anti-LKM1, western blotting WB for anti-M2) and with Cyto-Dot HM010. The one hundred and four sera were divided into five groups: Group I (n = 12) with anti-Jo-1 detected by ID; Group II (n = 28) with 26 anti-M2 positive by IF and WB, 2 anti-M2 positive only by WB; Group III (n = 10) with anti-ribosomal protein detected by IF 5 of which precipitated by ID; Group IV (n = 32) with anti-LKM1 by IF and ID divided into 18 AIH2 and 14 HCV; Group V (n = 22) consisting of 14 healthy individuals and 8 patients with hypergammaglobulinemia. Results of this study are similar to those of Cyto-Dot HM010 for the three auto-antibodies already in use. Cyto-Dot 4 is a very good anti-LKM1 confirmation method as it is ID.

[Proteomic analysis associating two-dimensional electrophoresis and mass spectrometry to identify lacrimal proteins: a case study]. / Apport de l'analyse protéomique associant électrophorèse bi-dimensionnelle et spectrométrie de masse en lacrymologie.

PURPOSE: Identification of a lacrimal protein by proteomic analysis, i.e., two-dimensional electrophoresis and mass spectrometry. MATERIAL AND METHODS: We studied the tears of a 25-year-old female with adrenal gland hyperplasia and hyperandrogenism complaining of chronic dryness and mild bilateral papillary hypertrophy. An allergologic workup was negative. Agarose electrophoresis of the tears showed a bilateral high level of rapid migrated proteins. RESULTS: Dodecyl sulfate polyacrylamide gel electrophoresis of the tears from both eyes showed a highly stained 15-kDa band after Coomassie colloidal blue coloration compared to controls. On two-dimensional electrophoresis, this band focused on a single spot at pI 7.0. After tryptic digestion in gel, peptide mass fingerprint analysis by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry provided clear identification of cystatin SN. It is known that mRNA regulated by androgens and encoding glycoproteins homologous to human cystatin exists in the rat lacrimal gland. CONCLUSION: We conclude that the hyperandrogenism of the patient may be cause for the hypersecretion of this cystatin SN, giving an explanation for the high level of rapid migrated proteins (lipocalins). This result provides a concrete example of the proteomic tool used to identify lacrimal proteins, still largely unknown.

A 10 year follow up study of patients transplanted for autoimmune hepatitis: histological recurrence precedes clinical and biochemical recurrence.

BACKGROUND AND AIM: Autoimmune hepatitis (AIH) has been reported to recur after orthotopic liver transplantation (OLT) in 10-35% of patients in small series with a short follow up. The aim of the present study was to examine the clinical and histological outcome more than 10 years after OLT for AIH. PATIENTS AND METHODS: Seventeen women with a mean age of 30 (12) years at the time of OLT, selected from among 44 patients transplanted for AIH, were followed for more than 10 years. The criteria for definite AIH, as established by the International Autoimmune Hepatitis Group, were met in every case. Liver biopsies were performed 1, 2, 5, and 10 years after OLT, and when indicated by abnormal liver function tests. Specimens were examined for evidence of recurrent AIH, namely interface hepatitis, lobular activity, portal lymphoplasmocytic infiltration, and fibrosis. Other signs of recurrence included hypertransaminasaemia, serum autoantibodies, and the response to steroid reintroduction or significant steroid dose increments. RESULTS: AIH recurred in 7 (41%) of 17 patients. In four patients histological abnormalities were detected by means of protocol biopsies 1-5 years before the onset of biochemical abnormalities. Two patients developed severe recurrences after 10 and 15 years, respectively, and required treatment with steroids and tacrolimus. In the other three patients histological recurrence was detected 0.6-3 years post-OLT, concomitantly with biochemical abnormalities. CONCLUSIONS: AIH recurred in 41% of patients followed for more than 10 years after OLT. As histological signs preceded biochemical abnormalities in four patients (23.5%), regular liver biopsy is warranted after OLT. Detection of isolated histological signs may call for closer follow up and/or a change in immunosuppressive therapy.

Antibodies to soluble liver antigen: an additional marker in type 1 auto-immune hepatitis.

BACKGROUND/AIMS: Auto-immune hepatitis patients are divided into two well-defined subgroups on the basis of immunoserological markers, i.e. anti-actin cable and/or anti-nuclear antibodies for the auto-immune hepatitis type 1, anti-liver/kidney microsome type 1 and/or anti-liver cytosol type 1 for the autoimmune hepatitis type 2. Controversial antibodies to a soluble liver antigen have been proposed as a diagnostic marker for the putative auto-immune hepatitis type 3. The aim was to investigate the implication of anti-soluble liver antigen antibodies in the diagnosis of auto-immune hepatitis and their ability to define auto-immune hepatitis type 3. METHODS: Sera from 483 patients with hepatic and non-hepatic diseases, and 102 sera from blood donors were analyzed by an inhibition capture enzyme-linked immunosorbent assay. RESULTS: Anti-soluble liver antigen antibodies were found in 13 of the 106 (12%) auto-immune hepatitis type 1 patients and 10 of the 49 (20%) cryptogenic hepatitis patients tested. In contrast, they were not detected in auto-immune hepatitis type 2 (n=54), primary sclerosing cholangitis (n=37), primary biliary cirrhosis (n=52), hepatitis C virus infection (n=105), alcoholic hepatitis (n=25), various non-hepatic autoimmune disorders (n=55) and in healthy blood donors (n=102). The clinical and biological features of antisoluble liver antigen-seropositive patients were similar to those of auto-immune hepatitis type 1 and did not distinguish a subgroup of auto-immune hepatitis. CONCLUSION: The data support the concept that antisoluble liver antigen-positive cryptogenic hepatitis is similar to auto-immune hepatitis type 1. Anti-soluble liver antigen antibodies can be considered as an additional and specific auto-immune hepatitis type 1 diagnostic marker.

Detection on immunoblot of new proteins from the soluble fraction of the cell recognized either by anti-liver-kidney microsome antibodies type 1 or by anti-liver cytosol antibodies type 1--relationship with hepatitis C virus infection.

Antibodies directed against liver cytosol protein, called anti-liver cytosol type 1 (LC1 Ab), have been described by both immunofluorescence (IF) and immunodiffusion techniques in sera from patients with autoimmune hepatitis (AIH). They have never been found in association with antibodies directed against the hepatitis C virus (HCV), unlike the anti-liver-kidney microsome antibodies type 1 (LKM1 Ab), the serological marker of AIH type 2. This suggests that there are two subgroups of AIH type 2, i.e., HCV-related and non-HCV-related. In this study, immunoblotting experiments were performed using proteins from the soluble phase of the rat liver cell; 141 sera which tested positive for LKM1 Ab by IF, 24 identified as having LC1 Ab by IF, and 50 from blood donors as controls were analyzed. Three bands were stained by LC1 Ab sera more often than by the control sera, and with a statistically significant frequency. These 3 proteins were located at apparent Mr 50,000, 55,000, and 60,000. The LKM1 Ab-positive sera as defined by IF stained six bands with a statistically significant frequency compared to the controls. Their apparent Mr were 35,000, 39,000, 47,000, 50,000, 55,000, and 60,000. LKM1 Ab-positive sera which were anti-HCV negative recognized a 60,000 protein belonging to the soluble phase of the cell, with a statistically significant frequency compared to LKM1 Ab-positive sera which were anti-HCV positive. This 60,000 protein was also recognized by LC1 Ab-positive sera, which were almost always anti-HCV negative. The presence of antibodies against a 60,000 protein from the soluble phase of the cell is discussed in terms of the anti-HCV serological markers found in the sera from patients with AIH.

Detection on immunoblot of new proteins from the microsomal fraction recognized by anti-liver-kidney microsome antibodies type 1.

Previous studies have demonstrated that sera from patients with autoimmune hepatitis type 1 contain antibodies which react with proteins other than the endoplasmic reticulum integral membrane protein of apparent Mr 50,000, now known to be a cytochrome P450 of the IID subfamily. Sera from 141 patients found by immunofluorescence to be positive for anti-liver-kidney microsome antibodies type 1, and sera from 50 blood donors used as controls, were analyzed by immunoblotting experiments on rat liver microsomes, microsomal subfractions, and also microsomes subjected to various treatments, as described in the text. These fractions were characterized morphologically by electronic microscopy and biochemically by different enzymatic activities. Five bands were found to be stained more often by the patients' sera than by the controls' and with a statistically significant difference in frequency. These antigenic proteins were located at apparent Mr 62,000, 58,000, 50,000, 40,000, and 35,000. The 50,000 protein was of course more often stained than the others. Antibodies against these antigens belonged essentially to the IgG1 subclass. For some of them, subcellular localization and membrane topography are discussed. Interestingly, the 58,000 protein is not an integral membrane protein.

Aberrant function and long-term survival of mouse beta cells exposed in vitro to high glucose concentrations.

In vitro culture of murine Langerhans islets usually ends in islet death after 1-3 wk. Given contradictory published data, we studied the influence of glucose on the function and survival of islets from DBA/2 mice. Islets were cultured on plastic microwells, using 1, 2, or 11 g/l glucose concentrations. Using our routine technique, insulin secretion was evaluated after islet incubation for 15 min in basal medium [(sIS), 1 g/l glucose], followed by 15 min in stimulating medium [(sIS), 3 g/l glucose, 20 mM/l arginine, 5 mM/l theoophylline]. Insulin secretion of islets cultured in 1 g/l glucose remained stable and normal over a period of 2 mo [Day 7: bIS, 6.3 +/- 3.1 microU/50 microliters; sIS, 16.6 +/- 6.8 microU/50 microliters. Day 60: bIS, 6.0 +/- 4.0 microU/50 microliters; sIS, 21.3 +/- 10.5 microU/50 microliters]. Islet morphology also remained normal. Islets cultured in 2 g/l glucose showed elevated insulin response under basal and stimulating conditions during 2-3 wk, followed by a dramatic drop in insulin secretion [Day 7: bIS, 19.5 +/- 5.7 microU/50 microliters; sIS, 80.9 +/- 10.7 microU/50 microliters. Day 60: bIS, 5.4 +/- 5.0 microU/50 microliters; sIS, 2.7 +/- 1.4 microU/50 microliters]. Severe morphologic alterations appeared rapidly and islet destruction was nearly complete by 60 days. At 11 g/l glucose, functional and morphological islet alterations were accelerated [Day 7: bIS, 10.3 +/- 2.7 microU/50 microliters; sIS, 18.8 +/- 4.9 microU/50 microliters. Day 21: bIS and sIS almost undetectable].(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of interleukin-1 on pancreatic beta cell function in vitro depend on the glucose concentration.

Insulin-dependent diabetes mellitus is characterized by progressive autoimmune destruction of pancreatic Beta cells mediated by ill-defined effector mechanisms. Experimental data suggest that cytokines, e.g. interleukin 1 and tumor necrosis factor, could play a fundamental role. The aim of this study was to analyze the effect of recombinant IL-1 beta (rIL-1 beta) on both islet functional capacity and morphology, using long-term cultures and various glucose concentrations. Islet cultured with 1 g/l (5.5 mmol/l) glucose maintained normal insulin- secretion and morphology for more than two months. In contrast, islets cultured with 2 g/l (11 mmol/l) glucose showed an altered insulin secretion and a shorter survival (40 days). At 11 g/l (60 mmol/l) glucose, islets died by 2 weeks of culture. rIL-1 beta exerted a cytotoxic effect on islet cells only when added to cultures containing supraphysiological glucose concentrations. But, in the presence of 1 g/l glucose, the addition of rIL-1 beta (40 ng/ml) for prolonged periods (14 days), did not alter islet function. Our results suggest that in auto-immune type I diabetes, IL-1 beta represents an aggravating factor in lesion formation more than a primary pathogenic mechanism.