Alberto Falorni

CTLA-4-Ig regulates tryptophan catabolism in vivo.

Cytotoxic T lymphocyte–associated antigen 4 (CTLA-4) plays a critical role in peripheral tolerance. However, regulatory pathways initiated by the interactions of CTLA-4 with B7 counterligands expressed on antigen-presenting cells are not completely understood. We show here that long-term survival of pancreatic islet allografts induced by the soluble fusion protein CTLA-4–immunoglobulin (CTLA-4–Ig) is contingent upon effective tryptophan catabolism in the host. In vitro, we show that CTLA-4–Ig regulates cytokine-dependent tryptophan catabolism in B7-expressing dendritic cells. These data suggest that modulation of tryptophan catabolism is a means by which CTLA-4 functions in vivo and that CTLA-4 acts as a ligand for B7 receptor molecules that transduce intracellular signals.

Consensus statement on the diagnosis, treatment and follow-up of patients with primary adrenal insufficiency

Primary adrenal insufficiency (PAI), or Addisons disease, is a rare, potentially deadly, but treatable disease. Most cases of PAI are caused by autoimmune destruction of the adrenal cortex. Consequently, patients with PAI are at higher risk of developing other autoimmune diseases. The diagnosis of PAI is often delayed by many months, and most patients present with symptoms of acute adrenal insufficiency. Because PAI is rare, even medical specialists in this therapeutic area rarely manage more than a few patients. Currently, the procedures for diagnosis, treatment and follow‐up of this rare disease vary greatly within Europe. The common autoimmune form of PAI is characterized by the presence of 21‐hydroxylase autoantibodies; other causes should be sought if no autoantibodies are detected. Acute adrenal crisis is a life‐threatening condition that requires immediate treatment. Standard replacement therapy consists of multiple daily doses of hydrocortisone or cortisone acetate combined with fludrocortisone. Annual follow‐up by an endocrinologist is recommended with the focus on optimization of replacement therapy and detection of new autoimmune diseases. Patient education to enable self‐adjustment of dosages of replacement therapy and crisis prevention is particularly important in this disease. The authors of this document have collaborated within an EU project (Euadrenal) to study the pathogenesis, describe the natural course and improve the treatment for Addisons disease. Based on a synthesis of this research, the available literature, and the views and experiences of the consortiums investigators and key experts, we now attempt to provide a European Expert Consensus Statement for diagnosis, treatment and follow‐up.

Autoantibodies against type I interferons as an additional diagnostic criterion for autoimmune polyendocrine syndrome type I

CONTEXT In autoimmune polyendocrinopathy syndrome type I (APS-I), mutations in the autoimmune regulator gene (AIRE) impair thymic self-tolerance induction in developing T cells. The ensuing autoimmunity particularly targets ectodermal and endocrine tissues, but chronic candidiasis usually comes first. We recently reported apparently APS-I-specific high-titer neutralizing autoantibodies against type I interferons in 100% of Finnish and Norwegian patients, mainly with two prevalent AIRE truncations. OBJECTIVES Because variability in clinical features and age at onset in APS-I frequently results in unusual presentations, we prospectively checked the diagnostic potential of anti-interferon antibodies in additional APS-I panels with other truncations or rare missense mutations and in disease controls with chronic mucocutaneous candidiasis (CMC) but without either common AIRE mutation. DESIGN The study was designed to detect autoantibodies against interferon-alpha2 and interferon-omega in antiviral neutralization assays. SETTING AND PATIENTS Patients included 14 British/Irish, 15 Sardinian, and 10 Southern Italian AIRE-mutant patients with APS-I; also 19 other patients with CMC, including four families with cosegregating thyroid autoimmunity. OUTCOME The diagnostic value of anti-interferon autoantibodies was assessed. RESULTS We found antibodies against interferon-alpha2 and/or interferon-omega in all 39 APS-I patients vs. zero of 48 unaffected relatives and zero of 19 British/Irish CMC patients. Especially against interferon-omega, titers were nearly always high, regardless of the exact APS-I phenotype/duration or AIRE genotype, including 12 different AIRE length variants or 10 point substitutions overall (n=174 total). Strikingly, in one family with few typical APS-I features, these antibodies cosegregated over three generations with autoimmune hypothyroidism plus a dominant-negative G228W AIRE substitution. CONCLUSIONS Otherwise restricted to patients with thymoma and/or myasthenia gravis, these precocious persistent antibodies show 98% or higher sensitivity and APS-I specificity and are thus a simpler diagnostic option than detecting AIRE mutations.

Increased risk for endocrine autoimmunity in Italian type 2 diabetic patients with GAD65 autoantibodies

Glutamic acid decarboxylase (GAD)65 autoantibodies (GAD65Ab) in type 2 diabetic subjects with secondary failure to sulphonylurea treatment identify the so‐called latent autoimmune diabetes of the adult (LADA). The aim of our study was to estimate the risk for endocrine autoimmunity in type 2 diabetic subjects with GAD65Ab.

Steroid-cell autoantibodies are preferentially expressed in women with premature ovarian failure who have adrenal autoimmunity.

OBJECTIVE To determine the prevalence of steroid-cell autoantibodies, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) antibodies, 17alpha-hydroxylase (17alpha-OH) antibodies, and P450 side-chain cleavage antibodies in premature ovarian failure. DESIGN Cross-sectional, observational study. SETTING Academic research hospitals. PATIENT(S) Eighty-one women with premature ovarian failure, 20 women with Addison disease not associated with premature ovarian failure, 42 women with type 1 diabetes mellitus, and 90 healthy women. MAIN OUTCOME MEASURE(S) Serum levels of steroid-cell autoantibodies, 17alpha-OH antibodies, P450 side-chain cleavage antibodies, and 3beta-HSD antibodies. RESULT(S) Steroid-cell autoantibodies were present in none of 57 women with isolated premature ovarian failure or premature ovarian failure plus nonadrenal autoimmune disease and in 21 of 24 (87%) women with Addison disease-related premature ovarian failure. 17alpha-Hydroxylase antibodies and P450 side-chain cleavage antibodies were significantly more frequent in women positive for adrenal autoantibodies than in those negative for adrenal autoantibodies (50% vs. 0% and 71% vs. 2%, respectively). The presence of 17alpha-OH antibodies or P450 side-chain cleavage antibodies was strongly associated with presence of steroid-cell autoantibodies. Two of 24 (8%) women with Addison disease-related premature ovarian failure and 1 of 57 (2%) women with isolated premature ovarian failure or premature ovarian failure plus nonadrenal autoimmune disease were positive for 3beta-HSD antibodies. None of 20 adult women with autoimmune Addison disease and none of 42 adult women with type 1 diabetes mellitus not associated with premature ovarian failure was positive for 3beta-HSD antibodies. CONCLUSION(S) Markers of steroid-cell autoimmunity are found only rarely in idiopathic premature ovarian failure not associated with Addison disease. Most women with Addison disease-related premature ovarian failure were positive for steroid-cell autoantibodies, 17alpha-OH antibodies, or P450 side-chain cleavage antibodies. 3beta-Hydroxysteroid dehydrogenase antibodies do not appear to be a major marker of steroid-cell autoimmunity.

Associations of GAD65- and IA-2-Autoantibodies With Genetic Risk Markers in New-Onset IDDM Patients and Their Siblings. The Belgian Diabetes Registry

OBJECTIVE To investigate the association of GAD (65-kDa) autoantibodies (GAD65-Abs) and IA-2 autoantibodies (IA-2-Abs) with human leukocyte antigen (HLA)-DQ and insulin gene (INS) risk markers in patients with recent-onset IDDM and their siblings. RESEARCH DESIGN AND METHODS Blood was sampled from 608 recent-onset IDDM patients and 480 siblings, aged 0–39 years and consecutively recruited by the Belgian Diabetes Registry, to determine GAD65- and IA-2-Ab (radiobinding assay), HLA-DQ- (allele-specific oligonucleotyping), and INS-genotypes (restriction fragment length polymorphism analysis; siblings, n = 439). RESULTS At the onset of IDDM, GAD65-Abs were preferentially associated with two populations at genetic risk but only in the 20- to 39-year age-group: 1) their prevalence was higher in carriers of DQA1*0301-DQB1*0302 (88 vs. 73% in non[DQA1*0301-DQB1*0302], P = 0.001), and 2) an association was found in patients lacking this haplotype but carrying DQA1*0501-DQB1*0201, together with INS I/I (87 vs. 54% vs. non[INS I/I], P = 0.003). Siblings of IDDM patients also presented the association of GAD65-Abs with DQA1*0301-DQB1*0302 (13 vs. 2% non[DQA1*0301-DQB1*0302], P < 0.001), while associations with the second genetic risk group could not yet be assessed. At the onset of IDDM, IA-2-Ab prevalence was higher in carriers of DQA1*0301-DQB1*0302 (69 vs. 39% non[DQA1*0301-DQB1*0302], P < 0.001) but not of DQA1*0501-DQB1*0201 or INS I/I. This association was present in both the 0- to 19- and the 20- to 39-year age-groups. It was also found in siblings of IDDM patients (4 vs. 0% non[DQA1*0301-DQB1*0302], P < 0.001). CONCLUSIONS Both GAD65- and IA-2-Abs exhibit higher prevalences in presence of HLA-DQ- and/or INS-genetic risk markers. Their respective associations differ with age at clinical onset, suggesting a possible usefulness in the identification of subgroups in this heterogeneous disease.

Body mass index in children and adolescents according to age and pubertal stage

Objective: To evaluate the dependence of body mass index (BMI) values on pubertal stage in subjects similar in age.Design, subjects and measurements: Height and weight were recorded cross-sectionally in school subjects from three provinces in central Italy. The subjects were subdivided into three groups: (1) 4271 school subjects (2125 males and 2146 females; 8.5–15.5 y old), in whom the pubertal development was also recorded, were selected to subdivide BMI values according to pubertal stage and age; (2) 6345 females (10.5–14.5 y old), who were asked whether or not they had had their first menstrual period, were selected to subdivide BMI values according to age in pre-menarche and post-menarche girls, separately; and (3) 1919 females (10.5–14.5 y old), who had presented their menarche within the previous 6 months, were selected to subdivide short-term post-menarche BMI values according to age.Results: The medians and interquartile ranges of BMI varied according to age and pubertal stage. Kruskall–Wallis test performed in subjects similar in age demonstrated that significant differences existed among the medians of BMI values of subjects at different pubertal stages in 12–14-y-old males (P<0.05), and in 11–14-y- old females (P<0.001). The difference also proved to be significant between stage I and stage II (P<0.05) in 10-y-old females, but not in 10–11-y-old males. The Kruskal–Wallis test performed in subjects similar in pubertal stage demonstrated that significant differences among the medians of BMI at different ages existed only in females at stages II and III. A significant positive trend was observed in both genders according to pubertal stage for BMI values of subjects similar in age (z-test for trend, P<0.01). On the contrary, a negative age trend proved to be significant in females at stages I (P<0.01), II (P<0.01) and III (P<0.001), but not in males when the subdivision of BMI was made according to age in subjects similar in pubertal stage. BMI values were significantly higher in post-menarche girls as compared to pre-menarche girls similar in age (P<0.001). However, at partial regression analysis BMI values were influenced by pubertal stage and, to a lesser extent, by age, but not by menarcheal status. An inverse association between short-term post-menarche BMI and age was observed, with the highest values in girls presenting menarche at 11 y of age (P<0.05). The negative trend was demonstrated at the z-test for trend (P<0.001).Conclusions: BMI values depend on pubertal degree of maturation, especially in girls. This influence should be taken into account when BMI is evaluated in adolescents.Sponsor: University of Perugia, Region of Umbria.Eyropean Journal of Clinical Nutrition (2000) 54, 214–218

Autoantibodies in autoimmune polyendocrine syndrome type II

The autoimmune polyendocrine syndrome type II (APS-II) is characterized by the association of autoimmune Addisons disease with thyroid autoimmune diseases or type-1 diabetes mellitus. 21-Hydroxylase autoantibodies enable the accurate diagnosis of autoimmune Addisons disease and, in patients with other endocrine autoimmune diseases, identify subjects at high risk for clinical adrenal insufficiency. 17 alpha-Hydroxylase (17OH) and side-chain-cleavage enzyme (P450scc) are target autoantigens of steroid-cell autoantibodies, and in women with Addisons disease, 17OH autoantibodies and P450scc autoantibodies are markers of increased risk for premature ovarian failure. Thyroperoxidase autoantibodies, thyroglobulin autoantibodies, H+/K(+)-ATPase autoantibodies, and GAD65 autoantibodies are frequently detected in patients with isolated Addisons or APS-II. Screening for other organ-specific autoimmune diseases should be performed in every patient with at least one major disease component of APS-II.

Large incidence variation of Type I diabetes in central-southern italy 1990-1995 : lower risk in rural areas

Aims/hypothesis. To evaluate the relation between the incidence of childhood Type I (insulin-dependent) diabetes mellitus and the degree of urbanization in the central-southern part of Italy. Methods. The incidence was determined in two areas: area A encompasses 3 regions of central-eastern Italy (Marche, Abruzzo, Umbria), whereas area B encompasses one southern region (Campania). During 1990–1995, 706 children aged 14 or under with insulin-dependent diabetes mellitus of recent onset were registered. The completeness of the case ascertainment in the registries analysed separately for each region was high, ranging from 96.3 % to 99 %. Results. The age-standardized incidence was higher in area A (9.6 per 100 000 person per year; 95 % confidence interval: 8.5–10.8) than in area B (5.4 per 100 000 person per year; 95 % confidence interval: 4.9–6.0). In both areas the standardized incidence ratios increased with the degree of urbanization (chi-squared for trend: area A = 140, p < 0.0001; area B = 79, p < 0.0001). The highest standardized incidence ratios were in the most urban communities. Conclusion/interpretation. This study showed a statistically significant difference in incidence of childhood insulin-dependent diabetes mellitus among different areas of the continental peninsula of Italy. People living in the rural communities appear to have a lower risk. [Diabetologia (1999) 42: 789–792]

A method for the massive separation of highly purified, adult porcine islets of langerhans

A method for the massive and reproducible isolation of highly purified, adult porcine islets of Langerhans is described. The successful combination of donor animal-strain selection with original procedures for pancreas retrieval and enzymatic digestion permitted us to separate uniquely massive concentrations of pure porcine islets with no need for mechanical disruption of the pancreatic tissue. Following our procedure, porcine islets, which fully retain viability and function, can be harvested easily and rapidly. Xenotransplantation of such islets, immunoprotected within algin/polyaminoacidic microcapsules, was associated with complete reversal of hyperglycemia in rodents with either spontaneous or streptozotocin-induced diabetes mellitus.