Immunoreactivities Against Different Tyrosine-Phosphatase 2 (IA-2)(256-760) Protein Domains Characterize Distinct Phenotypes in Subjects With LADA.

Antibodies (Abs) against intracellular epitopes of the tyrosine-phosphatase 2 (IA-2) are detected in type 1 diabetes. Abs directed against the IA-2(256-760) portion, with both intra- and extracellular epitopes, are present in people with latent autoimmune diabetes in adults (LADA) and in obese subjects with normal glucose tolerance (NGT). We aim to characterize distribution and clinical features of intra- and extra-cellular IA-2(256-760) immunoreactivities in people with LADA compared to obese people with NGT. The intracellular immunoreactivity represented by immune response against two intracellular IA-2 constructs (IA-2JM(601-630) and IA-2IC(605-979)) was analyzed and related to clinical and biochemical features in 101 people with LADA and in 20 NGT obese subjects, all testing positive for IA-2(256-760) Abs. IA-2 intracellular immunoreactivity showed a frequency of 40.6% in LADA while it was not detected among NGT obese (p<0.001). Amongst LADA, the presence of immunoreactivity against the IA-2 intracellular domains was associated with lower BMI, waist circumference, higher HDL cholesterol and lower triglycerides, lower prevalence of hypertension and higher prevalence of other autoimmune disorders. Immunoreactivity against IA-2 does not involve intracellular domains in the majority of LADA and in obese people with NGT. This study shows that there is heterogeneity in the IA-2 epitopes, associated with different clinical features.

Non-organ-specific autoimmunity in adult 47,XXY Klinefelter patients and higher-grade X-chromosome aneuploidies.

Current literature regarding systemic autoimmune diseases in X-chromosome aneuploidies is scarce and limited to case reports. Our aim was to evaluate the frequency of anti-nuclear (ANAs), extractable nuclear (ENA), anti-double-stranded DNA (dsDNAs), anti-smooth muscle (ASMAs) and anti-mitochondrial (AMAs) antibodies in a large cohort of adults with Klinefelter's syndrome (KS, 47,XXY) and rare higher-grade sex chromosome aneuploidies (HGAs) for the first time. Sera from 138 X-chromosome aneuploid patients [124 adult patients with 47,XXY KS and 14 patients with HGA (six children, eight adults)] and 50 age-matched 46,XY controls were recruited from the Sapienza University of Rome (2007-17) and tested for ANAs, ENAs, anti-dsDNAs, ASMAs and AMAs. Non-organ-specific immunoreactivity was found to be significantly higher in patients with 47,XXY KS (14%) than in the controls (2%, p = 0.002). Among all the antibodies investigated, only ANAs were observed significantly more frequently in patients with 47,XXY KS (12.1%) than in the controls (2%, p = 0.004). No anti-dsDNA immunoreactivity was found. Stratifying by testosterone replacement therapy (TRT), non-organ-specific autoantibody frequencies were higher in TRT-naive (p = 0.01) and TRT-treated groups than in controls. No patients with HGA were found positive for the various autoantibodies. Non-organ-specific autoantibodies were significantly present in 47,XXY adult patients. Conversely, HGAs did not appear to be target of non-organ-specific immunoreactivity, suggesting that KS and HGAs should be considered as two distinct conditions. The classification and diagnosis of systemic autoimmune diseases is frequently difficult. To support a correct clinical evaluation of KS disease and to prevent eventual secondary irreversible immune-mediated damages, we highlight the importance of screening for non-organ-specific autoimmunity in Klinefelter's syndrome.

Type 1 diabetes, thyroid, gastric and adrenal humoral autoantibodies are present altogether in almost one third of adult celiac patients at diagnosis, with a higher frequency than children and adolescent celiac patients.

Background: No data are available on the frequency of organ-specific humoral autoimmunity at diagnosis of adult celiac disease (CD).Aim: To evaluate the humoral immunoreactivities specific of type 1 diabetes (T1D), thyroid (THD), atrophic-gastritis (AG) and Addison's (AD) diseases in 92 adult CD patients at diagnosis and 237 adult healthy subjects (CTRL).Methods: T1D, THD and AD specific autoantibodies were analyzed by radioimmunoprecipitation assays. AG autoantibodies were detected by enzyme-linked immunosorbent assay.Results: Of 92 CD patients, 31.5% were positive for at least one of the organ-specific autoantibodies investigated (p < .0001 vs CTRL). Thyroid, diabetes, gastric and adrenal-autoantibodies, that increase with age at diagnosis, were detected in 12.0%, 10.9%, 10.9%, 2.2% of CD patients, respectively. Gastric- and diabetes- rather than thyroid- and adrenal-autoimmunity seem to be specifically related to presence of CD.Conclusions: One third of adult CD patients at diagnosis is target of at least one organ-specific autoantibody. A systematic organ-specific autoantibody screening in these patients might be of value to promptly identify, prevent or treat the relative diseases.

Gluten-free diet impact on dynamics of pancreatic islet-specific autoimmunity detected at celiac disease diagnosis.

OBJECTIVE: Almost 6% of celiac disease (CD) patients at diagnosis are positive for at least one of the main pancreatic islet autoantibodies that characterize type 1 diabetes (T1D). Few information, dated back to almost two decades ago, exist as to whether a gluten-free diet (GFD) could reduce the islet-specific autoimmunity detected in patients at CD diagnosis. Aim of the study was to evaluate the impact of GFD on 31 patients who presented islet-specific autoimmunity at CD diagnosis. METHODS: CD patient sera collected at diagnosis and throughout the GFD were analyzed for the main humoral autoantibodies so far identified in T1D, directed against one or more among insulin, glutamic-acid decarboxylase, tyrosine-phosphatase 2, and zinc cation-efflux transporter autoantigens. RESULTS: GFD (median duration 39 months) was associated to a decrease or disappearance of the islet-specific autoantibodies in 71% of CD patients. Almost 80% of the patients who became autoantibody-negative during the GFD were positive for only one of the islet-specific autoimmune markers at CD diagnosis, with none of them developing diabetes. Conversely, 80% of the CD patients positive at diagnosis for ≥2 islet-specific autoantibodies were still positive after more than two years of GFD, with 25% of them developing T1D. CONCLUSIONS: Various factors appear to influence, individually or in combination, the effects of the GFD on pancreatic islet-specific autoimmune response detected at CD diagnosis. These factors include the number of diabetes autoantibodies found at CD diagnosis, the adherence to the GFD, its duration and an asymptomatic clinical presentation of CD.

Bisphenol A and Phthalates in Diet: An Emerging Link with Pregnancy Complications.

Endocrine-disrupting chemicals (EDCs) are exogenous substances that are able to interfere with hormone action, likely contributing to the development of several endocrine and metabolic diseases. Among them, Bisphenol A (BPA) and phthalates contaminate food and water and have been largely studied as obesogenic agents. They might contribute to weight gain, insulin resistance and pancreatic ß-cell dysfunction in pregnancy, potentially playing a role in the development of pregnancy complications, such as gestational diabetes mellitus (GDM), and adverse outcomes. Pregnancy and childhood are sensitive windows of susceptibility, and, although with not univocal results, preclinical and clinical studies have suggested that exposure to BPA and phthalates at these stages of life might have an impact on the development of metabolic diseases even many years later. The molecular mechanisms underlying this association are largely unknown, but adipocyte and pancreatic ß-cell dysfunction are suspected to be involved. Remarkably, transgenerational damage has been observed, which might be explained by epigenetic changes. Further research is needed to address knowledge gaps and to provide preventive measure to limit health risks connected with exposure to EDCs.

Gestational Diabetes Mellitus: The Impact of Carbohydrate Quality in Diet.

Gestational diabetes mellitus (GDM) is defined as "glucose intolerance that is first diagnosed during pregnancy". Mothers with GDM and their infants may experience both short and long term complications. Dietary intervention is the first therapeutic strategy. If good glycaemic control is not achieved, insulin therapy is recommended. There is no consensus on which nutritional approach should be used in GDM. In the last few years, there has been growing evidence of the benefits of a low glycaemic index (LGI) diet on diabetes and cardiovascular disease. The effect of a LGI diet on GDM incidence has been investigated as well. Several studies observed a lower incidence of GDM in LGI diet arms, without adverse maternal and fetal outcomes. The main positive effect of the LGI diet was the reduction of 2-h post-prandial glucose (PPG). Several studies have also evaluated the effect of the LGI diet in GDM treatment. Overall, the LGI diet might have beneficial effects on certain outcomes, such as 2-h PPG, fasting plasma glucose and lipid profile in patients with GDM. Indeed, most studies observed a significant reduction in insulin requirement. Overall, according to current evidence, the LGI nutritional approach is safe and it might therefore be considered in clinical care for GDM.

Evidence of diabetes-specific autoimmunity in obese subjects with normal glucose tolerance.

BACKGROUND: Recently, significant attention has been paid to the possible activation of an autoimmune response in the presence of obesity. The aim of this study was to evaluate and compare the frequencies of autoantibodies typical of autoimmune diabetes in obese patients with normal glucose tolerance (NGT), obese patients with type 2 diabetes (T2D) and controls. We also evaluated the presence of immunoreactivity to Hashimoto's thyroiditis and autoimmune gastritis. MATERIALS AND METHODS: Consecutive sera from obese patients, 444 with NGT, 322 with T2D, and 212 controls were analysed by radioimmunoassay or enzyme-linked immunosorbent assay for glutamic acid decarboxylase, protein tyrosine phosphatase islet antigen-2 (IA-2)IC and IA-2(256-760) , islet beta-cell zinc cation transporter (ZnT8), thyroid peroxidase, and anti-parietal cell autoantibodies. RESULTS: Altogether the presence of organ-specific autoantibodies was significantly more frequent in obese patients with NGT (128/444, 28.5%) and obese with T2D (79/322, 24.5%) than in controls (36/212, 17%; P = 0.002). Thyroid peroxidase immunoreactivity was prevalent in all groups of subjects investigated. The frequencies of diabetes-specific autoantibodies were slightly higher in obese patients with NGT (20/444, 4.5%) than in obese with T2D (12/322, 3.7%) and controls (4/212, 1.9%). The anti IA-2(256-760) was the most frequent islet autoantibody in obese subjects with NGT (14/20, 70%). CONCLUSIONS: We observed significant evidence of immunoreactivity specific to diabetes, thyroid, and gastric-parietal cells in obese patients with NGT. The relatively higher frequency of the diabetes-related IA-2(256-760) autoantibodies in obese patients with NGT may suggest that this autoantibody could be associated with obesity the presence of obesity itself.

Evidence of increased humoral endocrine organ-specific autoimmunity in severe and classic X-chromosome aneuploidies in comparison with 46,XY control subjects.

OBJECTIVE: In literature, the importance of X-linked gene dosage as a contributing factor for autoimmune diseases is generally assumed. However, little information is available on the frequency of humoral endocrine organ-specific autoimmunity in X-chromosome aneuploidies. In our preliminary study, we investigated the endocrine organ-specific humoral autoimmunity relative to four different organ-specific autoimmune diseases in a group of adult 47,XXY KS patients and in adults 46,XY control males (type 1 diabetes, T1DM; Addison's disease, AD; Hashimoto thyroiditis, HT; autoimmune chronic atrophic gastritis, AG). The aim of the present study is to evaluate the frequency of autoantibodies (Abs) specific for T1DM, AD, HT, and AG in rarer higher grade X-chromosome aneuploidies (HGA) and in 47,XXY children. DESIGN AND METHODS: Samples from 192 Caucasian patients with an X-chromosome aneuploidy (176 patients (55 children, 121 adults) with 47,XXY karyotype (KS patients) and 16 HGA patients (eight children, eight adults)) recruited from Sapienza, University of Rome (2007-2017) were tested for Abs specific for T1DM (insulin-Abs, GAD-Abs, IA-2-Abs, Znt8-Abs), HT (TPO-Abs), AD (21-OH-Abs), and AG (APC-Abs). The results were compared to those found in 213 46,XY control subjects (96 children, 117 adults). RESULTS: Altogether humoral organ-specific immunoreactivity was found in 13% of KS and HGA patients, with a significantly higher frequency than in the controls (p=.008). Almost 19% of HGA patients were positive for at least one of the organ-specific Abs investigated compared to 12.5% of KS patients. The frequency of the overall immunoreactivity was higher in KS children than in KS adults. The frequency of diabetes-specific Abs was significantly higher in the patient cohort than in controls (p=.005). Thyroid- and gastric-specific autoimmunity was also found in KS and HGA patients, while adrenal-specific immunoreactivity was rare. CONCLUSIONS: These results suggest for the first time that the risk of endocrine organ-specific humoral autoimmunity progressively increases with the severity of X-chromosome polisomy. The screening for diabetes-, thyroid-, and gastric-specific autoimmunity should be considered in clinical practice for identifying rare and classic X-chromosome aneuploid patients at risk of developing organ-specific autoimmune diseases.

A combined form of hypothyroidism in pubertal patients with non-mosaic Klinefelter syndrome.

Klinefelter syndrome has been associated with thyroid abnormalities, the genesis of which is not yet fully clear. The aim of this study was to evaluate thyroid function in Klinefelter syndrome subjects during the pubertal period. Chemiluminescent microparticle immunoassay was used to analyze Thyroid-Stimulating Hormone, fT3 and fT4 concentration in serum samples from 40 Klinefelter syndrome pubertal boys with classic 47,XXY karyotype and 157 healthy age-matched controls. 13 Klinefelter syndrome patients also underwent Thyrotropin-Releasing Hormone testing to evaluate hypothalamic-pituitary function. fT3 levels were significantly lower in Klinefelter syndrome patients than in age-matched controls (p < 0.001). No significant differences were found for Thyroid-Stimulating Hormone (p = 0.138) or fT4 (p = 0.274), but the serum levels of Klinefelter syndrome patients tended to cluster around the lower part of the reference range for the assay. Three of the thirteen Klinefelter syndrome patients undergoing the Thyrotropin-Releasing Hormone test had an adequate response, one had a prolonged response at 60 min and nine responded inadequately. This study demonstrated for the first time that pubertal Klinefelter syndrome patients have significantly lower fT3 serum levels than do healthy age-matched boys, whereas Thyroid-Stimulating Hormone and fT4 are normal, albeit at the lower end of the reference range. Most patients showed an inadequate/prolonged response to pituitary stimulation with Thyrotropin-Releasing Hormone. These findings suggest a combined form of both central and peripheral hypothyroidism in Klinefelter syndrome boys during pubertal development.

No effects of oral vitamin D supplementation on non-alcoholic fatty liver disease in patients with type 2 diabetes: a randomized, double-blind, placebo-controlled trial.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is the most common hepatic disorder worldwide, reaching prevalence up to 90 % in obese patients with type 2 diabetes (T2D), and representing an independent risk factor for cardiovascular mortality. Furthermore, the coexistence of T2D and NAFLD leads to higher incidence of diabetes' complications and additive detrimental liver outcomes. The existence of a close association between NAFLD and hypovitaminosis D, along with the anti-inflammatory and insulin-sensitizing properties of vitamin D, have been largely described, but vitamin D effects on hepatic fat content have never been tested in a randomized controlled trial. We assessed the efficacy and safety of 24-week oral high-dose vitamin D supplementation in T2D patients with NAFLD. METHODS: This randomized, double-blind, placebo-controlled trial was carried out at the Diabetes Centre of Sapienza University, Rome, Italy, to assess oral treatment with cholecalciferol (2000 IU/day) or placebo in T2D patients with NAFLD. The primary endpoint was reduction of hepatic fat fraction (HFF) measured by magnetic resonance; as hepatic outcomes, we also investigated changes in serum transaminases, CK18-M30, N-terminal Procollagen III Propeptide (P3NP) levels, and Fatty Liver Index (FLI). Secondary endpoints were improvement in metabolic (fasting glycaemia, HbA1c, lipids, HOMA-IR, HOMA-ß, ADIPO-IR, body fat distribution) and cardiovascular (ankle-brachial index, intima-media thickness, flow-mediated dilatation) parameters from baseline to end of treatment. RESULTS: Sixty-five patients were randomized, 26 (cholecalciferol) and 29 (placebo) subjects completed the study. 25(OH) vitamin D significantly increased in the active treated group (48.15 ± 23.7 to 89.80 ± 23.6 nmol/L, P < 0.001); however, no group differences were found in HFF, transaminases, CK18-M30, P3NP levels or FLI after 24 weeks. Vitamin D neither changed the metabolic profile nor the cardiovascular parameters. CONCLUSIONS: Oral high-dose vitamin D supplementation over 24 weeks did not improve hepatic steatosis or metabolic/cardiovascular parameters in T2D patients with NAFLD. Studies with a longer intervention period are warranted for exploring the effect of long time exposure to vitamin D. TRIAL REGISTRATION: This trial was approved on July 2011 by the Ethics Committee of Policlinico Umberto I, Sapienza University of Rome, Italy, and registered at www.clinicaltrialsregister.eu number 2011-003010-17.

Screening of endocrine organ-specific humoral autoimmunity in 47,XXY Klinefelter's syndrome reveals a significant increase in diabetes-specific immunoreactivity in comparison with healthy control men.

The aim of this study was to evaluate the frequency of humoral endocrine organ-specific autoimmunity in 47,XXY Klinefelter's syndrome (KS) by investigating the autoantibody profile specific to type 1 diabetes (T1DM), Addison's disease (AD), Hashimoto thyroiditis (HT), and autoimmune chronic atrophic gastritis (AG). Sixty-one adult Caucasian 47,XXY KS patients were tested for autoantibodies specific to T1DM (Insulin Abs, GAD Abs, IA-2 Abs, Znt8 Abs), HT (TPO Abs), AD (21-OH Abs), and AG (APC Abs). Thirty-five of these patients were not undergoing testosterone replacement therapy TRT (Group 1) and the remaining 26 patients started TRT before the beginning of the study (Group 2). KS autoantibody frequencies were compared to those found in 122 control men. Six of 61 KS patients (9.8 %) were positive for at least one endocrine autoantibody, compared to 6.5 % of controls. Interestingly, KS endocrine immunoreactivity was directed primarily against diabetes-specific autoantigens (8.2 %), with a significantly higher frequency than in controls (p = 0.016). Two KS patients (3.3 %) were TPO Ab positive, whereas no patients were positive for AD- and AG-related autoantigens. The autoantibody endocrine profile of untreated and treated KS patients was not significantly different. Our findings demonstrate for the first time that endocrine humoral immunoreactivity is not rare in KS patients and that it is more frequently directed against type 1 diabetes-related autoantigens, thus suggesting the importance of screening for organ-specific autoimmunity in clinical practice. Follow-up studies are needed to establish if autoantibody-positive KS patients will develop clinical T1DM.

Tyrosine phosphatase-related islet antigen 2(256-760) autoantibodies, the only marker of islet autoimmunity that increases by increasing the degree of BMI in obese subjects with type 2 diabetes.

OBJECTIVE: Since patients with type 2 diabetes and positive for type 1 diabetes-specific antibodies have wide variations in BMI, this study evaluated whether the frequency and pattern of islet autoantibody positivity is related to BMI. RESEARCH DESIGN AND METHODS: Clinical and biochemical characteristics and islet autoantibodies including GAD and protein tyrosine phosphatases islet antigen-2 (IA-2)IC and IA-2(256-760) were evaluated in 1,850 patients with type 2 diabetes from the Non-Insulin Requiring Autoimmune Diabetes study cohort. BMI was evaluated in all patients, who were then subdivided in three groups according to BMI (<25, ≥25 to <30, and ≥30 kg/m(2)). RESULTS: Out of 1,850, 120 (6.5%) patients were positive for at least one of the following antibodies: GAD (4.1%), IA-2(256-760) (3.3%), or IA-2IC (1.1%). GAD and IA-2IC antibodies showed decreasing frequencies with increasing BMI (P < 0.0001 and 0.0006, respectively, for trend); in contrast, the frequency of IA-2(256-760) antibodies increased with increasing BMI (P = 0.005 for trend). Patients with type 2 diabetes positive for IA-2(256-760) alone showed a phenotype resembling classical obese type 2 diabetes, with higher BMI, waist circumference, and uric acid (P < 0.005 for all), lower thyroid peroxidase antibodies, and lower progression to insulin requirement than GAD antibody-positive patients (P = 0.04 and P = 0.0005, respectively). CONCLUSIONS: The IA-2(256-760) antibody appears to represent an antibody marker that mainly identifies a clinical phenotype very similar to obese type 2 diabetes, suggesting a possible different pathogenetic mechanism.

Long-standing type 1 diabetes: patients with adult-onset develop celiac-specific immunoreactivity more frequently than patients with childhood-onset diabetes, in a disease duration-dependent manner.

To assess the frequency of celiac-associated humoral autoimmunity in patients with long-standing childhood- and adult-onset type 1 diabetes (LDM1) and whether it occurs more frequently as the disease progresses. IgA-/IgG-anti-tissue transglutaminase (IgA-tTG and IgG-tTG) and IgA-/IgG-deamidated gliadin (DGP) antibodies were analyzed in 277 LDM1 sera (120 females; disease duration 19.3 ± 12.3 years, range 5.0-54.0 years). Of the 277 patients, 147 were childhood-onset LDM1 ((CH)LDM1) and 130 adult-onset LDM1 ((AD)LDM1); 6.1 % LDM1 sera were tTG- and/or DGP-antibody-positive, with a lower frequency among (CH)LDM1 as compared with (AD)LDM1 patients (3.4 vs 9.2 %, p = 0.048). Celiac-associated immunoreactivity was significantly more frequent in LDM1 with >15 years of disease duration (9.4 vs 2.9 % in those with ≤15 years, p = 0.042) and among them in (AD)LDM1 (14.7 vs 4.2 % (CH)LDM1, p = 0.043). Celiac disease humoral immunoreactivity should be screened not only at diabetes onset, but also in long-standing patients, especially adults with disease duration >15 years.

Anti-transglutaminase immunoreactivity and histological lesions of the duodenum in coeliac patients.

Coeliac disease (CD) is characterized by several markers, including anti-transglutaminase auto-antibodies (tTGAb) directed against multiple epitopes of the gliadin protein. We aimed to investigate the correlation among CD duodenal lesions, tTGAb titres and the immunoreactivity against tTG constructs. A total of 345 CD patients (209 females, 136 males, overall median age: 7.3 years) were tested for full-length (fl) tTGAb with a fluid-phase radioimmunoassay. Out of the total, 231 patients were also tested for immunoreactivity against tTG fragments (F1: a.a. 227-687 and F2: a.a. 473-687). Patients were classified according to diffuse (D), patchy (P) or bulb (B) histological lesions. All sera were found fltTGAb positive. Patients with D, P and B lesions had a mean Ab index of 0.84±0.39, 0.57±0.39 and 0.45±0.24, respectively. Mean tTGAb titre varied between D and localized (P+B) patients (0.84±0.39 versus 0.52±0.34, P < 0.0001). Overall, 86.1% of patients were F1 auto-antibody (F1Ab) positive (D: 89%, P: 75%, B: 40%; D versus P+B: P = 0.004) and 49% of patients were F2 auto-antibody (F2Ab) positive (D: 53%, P: 19%, B: 10%; D versus P+B: P = 0.0006). Of the D patients 50.7% showed combined F1Ab-F2Ab (D versus P+B: P = 0.001), whereas 60% of B patients were negative for both F1Ab and F2Ab (B versus D: P < 0.0001). Coeliac-specific tTGAb immunoreactivity correlates with the grading and extension of histological duodenal lesions in CD patients at diagnosis. The immunoreactivity against single and combined tTG fragments is significantly higher in patients with D lesions. This is the first evidence of a distinct coeliac-specific immunoreactivity in patients with different duodenal involvement.

The celiac iceberg: characterization of the disease in primary schoolchildren.

OBJECTIVE: Celiac disease (CD) has a prevalence of 0.55% to 1% in Italy. Identifying CD in schoolchildren to characterize CD iceberg and evaluate the effect of diagnosis in screening-detected children. METHODS: A total of 7377 5- to 8-year-old children were invited to participate. A total of 5733 salivary samples were collected and tested for anti-transglutaminase antibodies (tTGAb), using a fluid-phase radioimmunoassay. Salivary tTGAb-positive children were analyzed for serum antibodies (anti-endomysium antibodies, radioimmunoassay, and enzyme-linked immunosorbent assay tTGAb). Positive children underwent endoscopy and then started gluten-free diet (GFD) and periodical follow-up. RESULTS: Forty-six subjects were found salivary tTGAb-positive and 16 border-line. Forty-five of 46 and 5 of 15 of them were also serum antibody-positive. Forty-two children showed duodenal villous atrophy and 1 had only type 1 lesions. Three children started GFD without performing endoscopy. CD prevalence (including 23 previously diagnosed children with CD) was 1.2%. Considering all 65 celiacs in our sample, a silent CD was found in 64%, typical in 28%, atypical in 7%, and potential in 1%. All patients showed strict adherence to GFD, weight and stature increase, and well-being improvement. Eighty-five percent and all but 2 screening-detected children with CD had Italian parents. CONCLUSIONS: Our sample size, representative of primary schoolchildren of our region, demonstrated that CD prevalence is growing in Italy, with a modified clinical spectrum and iceberg deepness.

IgA anti-transglutaminase autoantibodies at type 1 diabetes onset are less frequent in adult patients and are associated with a general celiac-specific lower immune response in comparison with nondiabetic celiac patients at diagnosis.

OBJECTIVE: To evaluate the celiac-associated humoral autoimmunity in child, adolescent, and adult patients at type 1 diabetes (DM1) onset and to determine whether DM1 celiac-specific humoral immunoreactivity occurs similarly to that in nondiabetic patients at celiac disease (CD) diagnosis. RESEARCH DESIGN AND METHODS: IgA anti-transglutaminase autoantibody (IgA-tTGAb) was detected in 654 new-onset DM1 sera. IgA-tTGAb(+) DM1 sera were subsequently analyzed for IgG-tTG, deamidated gliadin (DGP), and actin antibodies, and results were compared with those found in 83 screen-detected nondiabetic patients at CD diagnosis. RESULTS: A total of 12.8% DM1 sera were IgA-tTGAb(+), with a lower autoantibody frequency in adult patients aged >18 years (6.8 vs. 15.1%, aged ≤18 years; P = 0.005). IgA-tTGAb titers, IgG-tTGAb, and DGPAb frequency/titers and mean number of celiac-autoantibody positivities per patient were significantly lower in IgA-tTGAb(+) DM1 compared with nondiabetic CD patients. CONCLUSIONS: Age of diabetes onset is negatively associated with risk of CD. The celiac-specific humoral immunoreactivity at DM1 onset is significantly lower compared with that found in nondiabetic patients at CD diagnosis.

CD8+ T-cell mediated self-reactivity in HLA-B27 context as a consequence of dual peptide conformation.

HLA-B2709 does not predispose for Ankylosing Spondylitis although it differs from B2705, the most common and AS-associated subtype in different ethnic groups, only for the substitution His116Asp. Therefore, a productive approach to elucidate the molecular mechanisms of the disease could be the comparison of these alleles. B2705 has been shown to display certain self-peptides enriched in basic residues i.e., pVIPR and pGR, in a dual conformation and this is accompanied by the presence of specific cytotoxic T cells in patients with AS. In this study, we convalidate our previous observation that B2709 healthy subjects do not possess primary reactivity towards pVIPR while showing a prompt CD8+ T cell response driven by pGR. Notably, in the B2709 context of presentation, pVIPR assumes only a single conformation in contrast with pGR which is dimorphic. These results suggest a possible general connection between the occurrence of double peptide conformation and the property of inducing specific autoimmune responses.