Spectrum of autoantibodies other than anti-desmoglein in pemphigus patients

BACKGROUND

Pemphigus is a life-threatening autoimmune blistering disease mediated by autoantibodies against adhesion molecule of the skin. Its concurrence with systemic and organ-specific autoimmune disease was described in case reports.

OBJECTIVES

To evaluate the presence of a broad spectrum of organ-specific and non-organ-specific autoantibodies other than anti-desmoglein antibodies in pemphigus patients.

PATIENTS AND METHODS

Serum samples were obtained from 105 pemphigus foliaceus (PF) patients, 51 pemphigus vulgaris (PV) patients and 50 controls. Both indirect immunofluorescence assay and ELISA were used to assess the presence of autoantibodies related to connective tissue diseases, autoimmune hepatitis, vasculitis, rheumatoid arthritis, coeliac disease, diabetes and thyroiditis.

RESULTS

Significant difference was observed between the three groups for anti-thyroglobulin antibodies in the pemphigus foliaceus group (18% vs. 4%, P=0.03). A significantly higher occurrence of IgM anti-cardiolipin (P=0.03), IgG anti-reticulin (P=0.01) and IgG anti-gliadin antibodies (P=0.008) were observed in the PV group. Cases with more than four autoantibodies were frequently positives for both anti-desmoglein 1 and anti-desmoglein 3.

CONCLUSION

Autoantibodies other than anti-desmoglein antibodies are not rare in pemphigus patients. Clinical and serological follow-up of pemphigus patients with positive autoantibodies are needed to clarify their impact in disease evolution.

Expression of Notch family members in cultured murine articular chondrocytes

The Notch family is involved in cell differentiation during embryogenesis. Osteoarthritic chondrocytes undergo morphological and biochemical changes leading to the de-differentiation process. In the study reported here, we were interested in the involvement of the Notch pathway in murine articular chondrocyte de-differentiation. Articular chondrocytes were subjected to several cell culture passages and treated with or without a Notch inhibitor, N-[N-(3, 5-difluorophenacetyl-L-alanyl)]-S-phenylglycine t-Butyl Ester (DAPT). Chondrocyte morphology was studied using optical microscopy. Immunocytochemistry and immunoblot were performed to study the expression of collagens and Notch family members. Without DAPT treatment, chondrocyte de-differentiation resulted in fibroblast-like morphology. This was confirmed by immunocytochemical staining and immunoblot analysis, which showed an increase in collagen type I (col I) and a decrease in collagen type II (col II) expression. With DAPT treatment, de-differentiation was delayed. Immunocytochemistry and immunoblot analysis showed during the first passages inhibition of col II expression, which then was re-instituted during the last passage, suggesting chondrocyte re-differentiation. In the study reported here, we showed that inhibition of the Notch receptor not only delayed the de-differentiation process, but also chondrocyte re-differentiation, which confirms the involvement of the Notch pathway in chondrocyte de-differentiation.

Ketosis-onset diabetes in Tunisian adults: immunological markers and beta-cell function

The aim of this study in Tunisia was to classify ketosis-onset diabetes in adult patients. All patients aged > 30 years without known diabetes, presenting with ketosis and admitted to our department were studied. Patients with secondary or gestational diabetes and those on corticoid therapy or with coinciding infection were excluded. The data included clinical characteristics, immunological markers and beta-cell function. Of the 63 patients, islet-cell antibodies were present in 27.0%, glutamic acid decarboxylase antibodies in 25.4% and thyrosin phosphatase antibodies in 19.0%. Beta-cell functional reserve was preserved in 54.0%. Our results confirm that patients with ketosis-onset diabetes mellitus in adulthood are a heterogeneous group.

[Recurrent rhinitis and pulmonary infections revealing celiac disease: case report]

Celiac disease is associated with a number of extra-gastrointestinal features such as hepatitis, arthralgia, and recurrent foetal loss. However respiratory involvement is an extremely rare disorder. We report a case of celiac disease revealed by bronchiectasia in a 39-year-old man. The patient reported a history of recurrent pulmonary infections and intermittent intestinal symptoms in childhood. Wegner granulomatosis was initially suspected because of rhinopulmonary involvement. Serum's patient was tested for ANCA and anti-tissue antibodies. The latest test was performed on histological sections from rat and revealed the presence of anti-reticulin antibodies. Further testing, for anti-tissue transglutaminase and anti-endomysium antibodies, revealed positive results. Celiac disease was confirmed by histological examination of intestinal biopsy. Pulmonary symptoms were improved on a gluten free diet suggesting a causal relationship between celiac disease and respiratory symptoms.

Pemphigus vulgaris and pemphigus foliaceus: similar prognosis?

BACKGROUND

Pemphigus is a rare, life-threatening, acquired autoimmune bullous dermatosis. The prognosis of pemphigus foliaceus (PF) is usually regarded as more favourable than that of pemphigus vulgaris (PV). Our study aims to compare the clinical course of PV and PF in 37 patients.

PATIENTS AND METHODS

We conducted a retrospective study over a period of eight years (1994-2001). The patients were referred during this period and were followed until December 2003. PF and PV were included based on clinical, histological and immunopathological criteria.

RESULTS

In our study there was no significant difference between PF group and PV group concerning; age, sex, duration of the disease, presence of disseminated lesions, treatment, healing time, remission, relapse, complications, death and follows up duration. The survival graph showed no difference between the two groups for the first two relapses. There was a tendency to significance concerning an additional treatment and relapses frequency in the PF group.

CONCLUSIONS

Few studies in the literature were interested in the evolution of the two forms of pemphigus. They showed that the two populations share the same clinical course; nevertheless they revealed the frequency of partial remission, failed treatment, relapses, necessity of high dose of corticosteroids, and difficulties of discontinuing treatment in PF. Our study, suggests that PF and PV may share the same clinical course.

[Prevalence of diabetes-related autoantibodies in celiac disease]

THE AIM

of this study is to investigate the prevalence of diabetes-related autoantibodies in a group of children with celiac disease and to compare it with a control group.

MATERIAL AND METHODS

We recruited 31 celiac children at diagnosis (on gluten containing diet) and 31 age and sex matched healthy children. Anti-islet cell antibodies (ICA) were detected by indirect immunofluorescence on monkey pancreas. Anti-glutamate decarboxylase (anti-GAD) and anti-tyrosine phosphatase (anti-IA2) antibodies were assessed by a radio-immuno- precipitation method.

RESULTS

Three out of 31 celiac patients (9.7%) had one or more diabetes-related autoantibodies. ICA, anti-GAD and anti-IA2 were found in respectively 3.2%; 3.2% and 9.7% of patients. Only one control (3.2%) had anti-GAD. There was no statistically significant difference between the 2 groups.

CONCLUSION

The risk to develop diabetes seems to be the same in celiac patients and in healthy subjects thus screening of diabetes-related autoantibodies is not justified in celiac patients.

Physiopathologie de l'arthrose. Du cartilage normal au cartilage arthrosique: facteurs de prédisposition et mécanismes inflammatoires

INTRODUCTION

osteoarthritis is the most prevalent form of arthritis in the world. With the progressive ageing of the population, it becomes a major problem of public health. Osteoarthritis is a degenerative affection characterized by many disorders leading to a structural and functional defect of one or several joints.

CURRENT KNOWLEDGE AND KEY POINTS

In this review, we focus on the main inflammatory mechanisms occurring in cartilage during primary osteoarthritis. We also describe some well established risk factors involved in the pathogenesis of this disease such as age, overload and genetic factors. Indeed, osteoarthritis is the result of an imbalance between the processes of degradation and the attempts of repair by the chondrocyte which is the exclusive cell type in cartilage. Degradation is induced by several chemical substances such as proteolytic enzymes (metalloproteinases) and pro-inflammatory cytokines especially interleukin 1beta. To face these events, the chondrocyte starts attempts of repair by secreting growth factors (Transforming Growth Factor and Insulin Growth Factor) or anti-inflammatory cytokines (interleukins 4 and 10) unsuccessfully. All these events will lead to the structural modifications observed in the osteoarthritic cartilage.

PROSPECTS

A better comprehension of the physiopathology of osteoarthritis will allow an improvement of therapeutic strategies of this common and invalidating disease.

[Prevalence of celiac disease serological markers in Tunisian type 1 diabetic adults]

OBJECTIVE

to evaluate the prevalence of celiac serological markers; anti-transglutaminase (ATGt), anti-endomysium (AE), anti-gliadin (AGD) and anti-reticulin (AR) antibodies; in type 1 diabetic Tunisian adults.

SUBJECTS AND METHODS

261 type 1 diabetic patients aged from 16 to 60 years were enrolled in this prospective study. IgG and IgA transglutaminase and gliadin were measured with ELISA. IgA AE were tested by indirect immunofluorescence using 2 substrates; monkey oesophagus and human umbilical cord. AR were detected by indirect immunofluorescence on rat liver, kidney and stomach. Sera IgA level was measured by turbidimetry.

RESULTS

83/261 of diabetics were positive for at least one antibody, 5.7% had ATGt-A, 3.4% AE on monkey esophagus, 3.1% AE on umbilical cordon, 18% AGD-A, 19.5% AGD-G and 3.1% AR. There was an excellent concordance between AE and ATGt (r = 0.9). Out of the 261 diabetics, 5 had an IgA deficiency and one of them has IgG AE and ATGt.

CONCLUSION

serological markers of celiac disease seem to be frequent in diabetics. Nevertheless, diagnosis must be confirmed by histological studies which allow us to know the real prevalence of celiac disease in diabetic adults.

[Complement protein hereditary deficits during purulent meningitis: study of 61 adult Tunisian patients]

Sixty one Tunisian adult patients with bacterial meningitis were screened for complement deficiency. Functional activity of the classical and the alternative pathways of complement (CH50 and AP50 respectively) were measured according to standard haemolytic procedures. Serum concentrations of C3 and C4 were determined by nephelometry. Late complement component (C5-C9) and properdin concentrations were assessed by double-ligand EISA. Complement deficiency was found in eight patients (13%): Seven had late complement component deficiency (three C7 deficiency, two C5 deficiency, one C6 deficiency and one C8 deficiency) and one had partial properdin deficiency. Patients with late complement component deficiency had a mean age of 24 years (range 17-32 years). All deficient patients had meningococcal meningitis. Recurrent meningitis was reported in half of the patients. Our findings demonstrated a high prevalence of complement deficiency in Tunisia suggesting that screening for hereditary complement deficiency should be performed in case of bacterial meningitides and meningococcal disease patients.

Celiac disease in adult patients with type 1 diabetes mellitus in Tunisia

OBJECTIVE

Type1 diabetes mellitus may be associated with celiac disease. The prevalence of celiac disease as determined by screening among adult patients with type 1 diabetes is high with rates of 1.07.8% in Europe and U.S.A. The aims of the study are to determine the prevalence of celiac disease in adults with type 1 diabetes in Tunisia.

METHODS

348 consecutive adult patients with type1 diabetes were investigated prospectively and screened for celiac disease. The mean age was 28.45+/-10.74 years old. There were 176 females and 172 males. For the screening of celiac disease, we used immunoglobulin A (IgA) anti-endomysium (EMA) antibodies determined by an indirect immunofluorescence method. Anti-transglutaminase (tTG) antibodies were determined by an ELISA method. Those patients with positive results for anti EMA and or tTG were proposed for duodenal biopsy.

RESULTS

14 patients were positive for anti EMA and had high or a weak positive level of tTG antibodies. One patient from this group was already known to have celiac disease. Only 8 patients consented to biopsy and morphological changes were consistent with celiac disease in all cases. Prevalence of biopsy-proven celiac disease was 2.3% (95% CI=1.0-4.5%).

CONCLUSION

The present study confirms that celiac disease of adults is prevalent in type 1 diabetic patients in Tunisia. Serological screening for celiac disease in type 1 diabetes is important because many patients are asymptomatic and most are detected by the screening.

Anti-desmoglein 1 antibodies in Tunisian healthy subjects: arguments for the role of environmental factors in the occurrence of Tunisian pemphigus foliaceus

Pemphigus foliaceus is an autoimmune blistering skin disease mediated by autoantibodies directed against desmoglein 1 and occurs as a sporadic form throughout the world, or as an endemic form called fogo selvagem in Brazil. Healthy subjects living in Brazilian endemic areas produce antidesmoglein 1 antibodies, suggesting the role of environmental factors in the initiation of the autoimmune response. Tunisia was described recently as an endemic area where the disease is characterized by its high rate among young people, especially women. An enzyme-linked immunosorbent assay using recombinant desmoglein 1 as antigen was used to detect antibodies against desmoglein 1 and calibrated with sera from 67 French healthy blood donors, 20 French pemphigus foliaceus patients and patients with other bullous skin diseases. When sera from 179 healthy Tunisian blood donors were tested, 31 (17%) were found positive. The desmoglein 1 binding activity of these 31 sera was confirmed in 10 cases by indirect immunofluorescence analysis and/or immunoblotting using human epidermal extract. Subclass analysis of antidesmoglein 1 antibodies showed that they were almost exclusively of the IgG2 subclass in positive normal sera and of IgG4 subclass in patients with PF. Thus, antibodies against desmoglein 1 are prevalent in normal subjects living in Tunisia which, along with their IgG2 isotype, suggests the role of the environment in the pathogenesis of this endemic type of pemphigus foliaceus and the need for additional factors to switch from a subclinical to a clinical form of the disease.

[Prevalence of serologic markers in celiac disease in trisomy 21 in Tunisia]

PURPOSE

This study was aimed to investigate the prevalence of serologic markers of celiac disease in Tunisian patients with trisomy 21.

METHODS

Twenty seven patients with trisomy 21 were prospectively screened by indirect immunofluorescence for anti-reticulin and anti-endomysium antibodies, and by an ELISA method for anti-gliadin and anti-transglutaminase antibodies. None of the 27 patients had known celiac disease at the time of the study.

RESULTS

Anti-reticulin, anti-endomysium, anti-gliadin and anti-transglutaminase antibodies were found in respectively 11%, 11%, 18.5%, and 14.8% of cases. Only one patient with all serologic markers of celiac disease underwent biopsy which shows a villous atrophy.

CONCLUSION

Anti-endomysium and anti-transglutaminase antibodies are good immunologic markers for the screening for celiac disease, a screening which is justified in patient with trisomy 21.

Tunisian endemic pemphigus foliaceus is associated with desmoglein 1 gene polymorphism

Desmoglein 1 is the target antigen and probably the initiating immunogen of the autoantibody response in pemphigus foliaceus (PF), a blistering autoimmune skin disease. We previously showed that the desmoglein 1 gene (DSG1) is polymorphic and that one of its variants is associated with the sporadic form of PF observed in France. Herewith, we report, based on a case-control analysis, that the same DSG1 polymorphism participates in susceptibility to the endemic form of PF seen in Tunisia and, thus, show that common genetic factors govern the breakage of tolerance to desmoglein 1 in different epidemiological and environmental situations.

[Antiphosphoplipid antibodies and retinal occlusive vasculopathy]

PURPOSE

to determine the prevalence of antiphospholipid antibodies in patients with occlusive retinal vascular events, exempt from conventional risk factors of retinal thrombosis.

METHODS

eleven patients with retinal vascular occlusion, free of main accepted risk factors for retinal thrombosis, were retrospectively screened for antiphospholipid antibodies (anticardiolipin and anti-beta2 glycoprotein 1 antibodies) by an Elisa method. Prevalence of antiphospholipid antibodies were compared with those in a homogenous control group of 100 patients.

RESULTS

the prevalence of antiphospholipid antibodies in the study group was 27% (three of 11). Comparison with control group prevalence (3%) showed a statistically significant difference (p < 0,001). One patient in the study disclosed positivity for IgG anticardiolipine antibodies, one for IgM anticardiolipine antibodies and one for anti-beta2 glycoprotein 1 antibodies.

CONCLUSION

our results lead us to recommend a systematic search for specific antiphospholipid antibodies in such young patients which could have an importance for the diagnosis of primary antiphospholipid syndrome.

Pemphigus is not associated with allotypic markers of immunoglobulin kappa

The kappa light chain constant region of immunoglobulins bears polymorphic markers involved in susceptibility to various autoimmune diseases. To determine whether it also contributes to the occurrence of pemphigus, a group of autoimmune blistering skin diseases owing to pathogenic autoantibodies, the genotypic frequencies of Km allotypes were evaluated in patients with pemphigus foliaceus or pemphigus vulgaris and ethnically-matched healthy controls in both Tunisia and France. No difference in the distribution of Km genotype or allele frequencies was observed between patients and controls in either countries. Therefore, Km allotypes do not appear to constitute a genetic factor contributing to pemphigus.

[Tuberculosis, primary biliary cirrhosis and autoimmunity (apropos of a case in Tunisia)]

We report the case of a 70 year-old Tunisian patient who developed antimitochondrial antibodies and anti-ADN during urogenital tuberculosis with clinical and biological signs of primary biliary cirrhosis and systemic lupus erythematosus. We discuss the association of the three diseases and the etiopathogeny of the autoimmune mechanisms induced by Mycobacterium tuberculosis.

Identification of a new antibody population directed against a desmosomal plaque antigen in pemphigus vulgaris and pemphigus foliaceus

Pemphigus vulgaris and pemphigus foliaceus are characterized by autoantibodies directed against transmembrane glycoproteins of desmosomes. F12, a human monoclonal autoantibody that binds to the desmosomal plaque, recognizes a 180-190-kDa doublet when immunoblotted against bovine tongue epithelium. Because F12 was derived from the peripheral blood lymphocytes of a patient with pemphigus vulgaris, we looked for the presence of anti-180-190-kDa antibodies in pemphigus vulgaris and pemphigus foliaceus serum. By immunoblot analysis, a third of the pemphigus serum contained anti-180-190-kDa antibodies that belonged to IgG subclass 1 or 3, unlike those that recognized desmogleins 1 and 3 (IgG4). By immunoelectron microscopy analysis on human oral mucosa and human skin with mAb to human IgG3, pemphigus serum containing anti-180-190 kDa antibodies recognized desmosomal plaques. The presence of antibodies with F12 properties in pemphigus serum was further demonstrated by a rabbit anti-F12 idiotype antiserum that allowed detection of F12 idiotype in serum with anti-180-190-kDa antibodies. These results indicate that some pemphigus vulgaris and pemphigus foliaceus serums contain antibodies that react with both intra- and extracellular structures of desmosomes and further demonstrate the heterogeneity of the autoimmune response in both types of pemphigus.

Environmental control of the seasonal variations in the daily pattern of melatonin synthesis in the European hamster, Cricetus cricetus

Nocturnal patterns of pineal melatonin concentrations were measured at hourly intervals in the European hamster, Cricetus cricetus, maintained under different natural or experimental environmental conditions. There were pronounced variations in the night peak of pineal melatonin both in the duration and the amplitude of the melatonin peak and in the onset and decline of melatonin synthesis. The duration of the melatonin peak increased proportionally with increased dark period. The amplitude increased abruptly from LD 16/8 to LD 15/9 and remained constant in all other photoperiods. The onset of synthesis started 6:00 hours after the onset of darkness in LD 16/8, 15/9, and 14/10, while it started 4:00 hours after dark onset in shorter photoperiods (LD 12/12 and 10/14). This result is opposite to that observed in the rat. The decline of synthesis was delayed as darkness increased and was directly related to lights on in long photoperiods, while it was endogenous in short photoperiods. Temperature, under a long photoperiod, also seems to be implicated in the regulation of the amplitude of the melatonin peak.

Absence of the alpha-1-antitrypsin PI*Z allele in Tunisia substantiates the particular genetic structure of African populations

Alpha-1-antitrypsin (PI) phenotypes were studied in a sample of 450 Tunisians. The observed frequencies of PI alleles were identical to those in African populations, with a very low incidence of PI*S and virtual absence of PI*Z. Such figures are similar to estimates in Asians and clearly opposite to those in Europeans. Am. J. Hum. Biol. 9:223-224, 1997. © 1997 Wiley-Liss, Inc.

Brain and pituitary melatonin receptors in male rat during post-natal and pubertal development and the effect of pinealectomy and testosterone manipulation

Using quantitative autoradiography, melatonin receptors have been studied during post-natal and pubertal development of the rat in 2 brain and 2 pituitary structures. In the pars distalis of anterior pituitary, melatonin receptors decrease gradually in density after birth and disappear in 30 day-old animals. In contrast melatonin binding is only expressed in the paraventricular nuclei of the thalamus at the age of 21-23 days and is always present in adult animals. In the suprachiasmatic nuclei and in the pars tuberalis of the pituitary, melatonin receptor density decreases after birth, remains stable for approximately 1 month and increases again at puberty to reach the birth values in the adult. This increase was absent in pinealectomized and in castrated animals but present in castrated animals receiving testosterone suggesting that it depends upon circulating testosterone and melatonin levels. These results show that melatonin receptors are differentially regulated during post-natal development in each of the 4 structures studied, and that melatonin and testosterone are 2 factors which could be involved in the regulation of melatonin receptor density in the suprachiasmatic nuclei and pars tuberalis.

Influence of maternal melatonin on melatonin receptors in rat offspring

Using quantitative autoradiography, we have studied the influence of maternal plasma melatonin on the expression and density of melatonin receptors in the brain and pituitary of rat offspring. At birth, the same structures displayed melatonin receptors whether the rats were born to and reared by intact or pinealectomized dams. The receptor density was, however, about 20% lower in the group born to pinealectomized dams. At postnatal day 9, when the pups of both groups synthetize rhythmically their own melatonin, this difference was suppressed. These results indicate that melatonin does not appear to be a requirement for the expression of its receptors, but seems to play a stimulatory role in their synthesis.

Delta-sleep-inducing peptide stimulates melatonin, 5-methoxytryptophol and serotonin secretion from perifused rat pineal glands

The pineal gland is known to synthesize numerous indolamines. Since delta-sleep-inducing peptide (DSIP, a tryptophan nonapeptide) is found in the pineal gland, its effect on the secretion of indolamines was investigated. DSIP stimulated melatonin (MEL), 5-methoxytryptophol (5-ML) and serotonin (5-HT) synthesis and release, whereas it did not affect pineal cyclic AMP levels. The stimulatory effect of DSIP on MEL secretion was dose dependent between 5 x 10(-6) and 10(-4) M, whereas the minimal effective concentration of DSIP on 5-ML secretion was higher than 10(-5) M. The effect of DSIP (10(-4) M) was compared to the effect of isoproterenol (ISO, 10(-6) M) on MEL and 5-HT release. ISO stimulated MEL secretion and concomitantly decreased 5-HT release. With regard to kinetic characteristics, the effect of DSIP (10(-4) M) on MEL release was faster and of shorter duration than the effect of ISO (10(-6) M; 2 and 4 h, respectively). At 10(-4) M, DSIP potentiated the ISO-induced increase of MEL secretion. The DSIP-stimulated release of MEL was not significantly altered when the pineal glands were treated with 10(-5) M propranolol (a beta-adrenergic antagonist), 10(-5) M prazosin (an alpha 1-adrenergic antagonist) or 10(-5) M naloxone (an opioidergic antagonist). This study demonstrates that the DSIP-induced secretion of indolamines from rat pineal glands may not be elicited through the well-known noradrenergic or opioid systems.

[Determination of hemoglobin in gastric juice]

Among the complications of surgical operations gastric haemorrhages are often unpredictable. Detecting them during the infraclinical stage is possible by measuring hemoglobin in the gastric juice. We have adopted a method allowing the measurement of very low concentrations of hemoglobin.