OBJECTIVE—Wolfram syndrome is an extremely rare autosomal-recessive disorder that predisposes the development of type 1 diabetes in association with progressive optic atrophy. The genetic basis of this disease has been shown to be due to mutations in the WFS1 gene. The WFS1 gene encodes a novel transmembrane protein called wolframin, which recent evidence suggests may serve as a novel endoplasmic reticulum calcium channel in pancreatic β-cells and neurons. Genotype-phenotype correlations in this syndrome are becoming apparent and may help in explaining some of the variable characteristics observed in this disease. RESEARCH DESIGN AND METHODS—In this report, we have studied 13 patients with Wolfram syndrome from nine families to further define the relationship between mutation site and type with specific disease characteristics. RESULTS—A severe phenotype was seen in patients with mutations in exon 4 and with a large deletion encompassing most of exon 8. In total, nine novel mutations were identified as well as three new silent polymorphisms. CONCLUSIONS—Similar to all other mutation reports, most causative changes identified in the WFS1 gene occurred in exon 8, and only one was identified outside this region in exon 4.

Peutz-Jeghers syndrome (PJS) is a rare cancer predisposition, which is characterized by the presence of hamartomatous polyposis and mucocutaneous pigmentation. A significant proportion of both familial and sporadic forms of this disorder are associated with mutations in the STK11 (serine/threonine kinase 11)/LKB1 gene. In this report we present a series of Australian PJS cases, which suggest that mutations in the STK11 gene do not account for many families or patients without a family history. The most likely explanation is either the presence of another susceptibility gene or genetic mosaicism in the non-familial patients.

BackgroundLymphocytic hypophysitis is an organ-specific autoimmune disease of the pituitary gland. A specific and sensitive serological test currently does not exist to aid in the diagnosis.ObjectiveTo identify target autoantigens in lymphocytic hypophysitis and develop a diagnostic assay for these proteins.Design/methodsA pituitary cDNA expression library was immunoscreened using sera from four patients with lymphocytic hypophysitis. Relevant cDNA clones from screening, along with previously identified autoantigens pituitary gland-specific factor 1a and 2 (PGSF1a and PGSF2) and neuron-specific enolase (NSE) were tested in an in vitro transcription and translation immunoprecipitation assay. The corticotroph-specific transcription factor, TPIT, was investigated separately as a candidate autoantigen.ResultsSignificantly positive autoantibody reactivity against TPIT was found in 9/86 hypophysitis patients vs 1/90 controls (P=0.018). The reactivity against TPIT was not specific for lymphocytic hypophysitis with autoantibodies detectable in the sera from patients with other autoimmune endocrine diseases. Autoantibodies were also detected against chromodomain-helicase-DNA binding protein 8, presynaptic cytomatrix protein (piccolo), Ca2+-dependent secretion activator, PGSF2 and NSE in serum samples from patients with lymphocytic hypophysitis, but at a frequency that did not differ from healthy controls. Importantly, 8/86 patients with lymphocytic hypophysitis had autoantibodies against any two autoantigens in comparison with 0/90 controls (P=0.0093).ConclusionsTPIT, a corticotroph-specific transcription factor, was identified as a target autoantigen in 10.5% of patients with lymphocytic hypophysitis. Further autoantigens related to vesicle processing were also identified as potential autoantigens with different immunoreactivity patterns in patients and controls.

Autoimmune polyendocrine syndrome type 1 (APS1) is a rare monogenic autoimmune disorder caused by mutations in the autoimmune regulator (AIRE) gene. High‐titre autoantibodies are a characteristic feature of APS1 and are often associated with particular disease manifestations. Pituitary deficits are reported in approximately 7% of APS1 patients, with immunoreactivity to pituitary tissue frequently described. Using APS1 patient serum to immunoscreen a pituitary cDNA expression library, testis specific, 10 (TSGA10) was isolated. Immunoreactivity against TSGA10 was detected in 5/99 (5.05%) patients with APS1, but also in 5/135 (3.70%) systemic lupus erythematosus (SLE) patients and 1/188 (0.53%) healthy controls. TSGA10 autoantibodies were not detected in the serum from patients with any other autoimmune disease. Autoantibodies against TSGA10 were detectable from a young age in 4/5 positive APS1 patients with autoantibody titres remaining relatively constant over time. Furthermore, real‐time PCR confirmed TSGA10 mRNA to be most abundantly expressed in the testis and also showed moderate and low expression levels throughout the entire body. TSGA10 should be considered as an autoantigen in a subset of APS1 patients and also in a minority of SLE patients. No recognizable clinical phenotype could be found to correlate with positive autoantibody reactivity.

Lymphocytic hypophysitis is an organ-specific autoimmune disease characterised by destruction of pituitary hormone-secreting cells due to attack by self-reactive T lymphocytes. The spectrum of pituitary autoantibodies characterised by indirect immunofluorescence (IF) in these patients has not been substantially defined. The purpose of this study was to determine the spectrum of pituitary autoantibodies in 16 lymphocytic hypophysitis patients. Pituitary sections were prepared from guinea pigs and sera from 16 lymphocytic hypophysitis patients (13 biopsy proven and 3 suspected cases) and 13 healthy controls were evaluated for immunoreactivity to the pituitary tissue by immunofluorescence. A single patient was found to have high titre pituitary autoantibodies against guinea pig pituitary tissue. Immunoreactivity was directed against cells of the intermediate lobe. We present the case report of the patient who is a 24 year old woman that presented with headaches, polyuria and polydipsia. A uniformly enlarged pituitary mass was visible on MRI and a diagnosis of suspected lymphocytic hypophysitis was made. Based on our IF study, we postulate this patient has an autoimmune process directed towards the major cell type in the intermediate lobe, the melanotroph. Pre-adsorption with peptides representing adrenocorticotropic hormone, α-melanocyte stimulating hormone or β-endorphin did not affect the IF signal suggesting our patient's pituitary autoantibodies may target some other product of Proopiomelanocortin (POMC) processing, such as corticotrophin-like intermediate peptide or γ-lipoprotein. Alternatively, the autoantibodies may target a peptide completely unrelated to POMC processing.

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