Initiation of Continuous rhPTH Infusion With Insulin Pump in an Inpatient Setting

Hypoparathyroidism is one of the few remaining hormonal insufficiencies not treated with replacement of its missing hormone. Conventional therapy involves multiple daily oral doses of calcium, active vitamin D, and magnesium, which is not only cumbersome for patients, but carries risk of nephrocalcinosis and is inadequate in patients with enteral malabsorption. Subcutaneous parathyroid hormone 1-34 (PTH[1-34]) has been tested as a hormonal replacement therapy for treatment of hypoparathyroidism. PTH(1-34) delivered by continuous infusion via insulin pump decreases or eliminates the need for oral medications, stabilizes serum and urine calcium at normal levels with minimal fluctuation, and significantly reduces PTH doses. In this case report, we describe the clinical application of PTH(1-34) via insulin pump in an adolescent with autoimmune polyendocrinopathy syndrome type 1 (APS1). Transition to a PTH pump reduced hospital admissions for calcium abnormalities and allowed our patient to discontinue all scheduled daily conventional therapy.

Adrenal crisis prompted by SARS-CoV-2 infection in a patient with autoimmune polyglandular syndrome type 1 (APS type 1)

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The biophysical and biochemical properties of the autoimmune regulator (AIRE) protein

AIRE (for autoimmune regulator) is a multidomain protein that performs a fundamental function in the thymus and possibly in the secondary lymphoid organs: the regulation, especially in the sense of activation, of the process of gene transcription in cell lines deputed to the presentation of self-antigens to the maturing T lymphocytes. The apoptosis of the elements bearing T-cell receptors with critical affinity for the exhibited self-antigens prevents the escape of autoreactive clones and represents a simple and efficient mechanism of deletional self-tolerance. However, AIRE action relies on an articulated complex of biophysical and biochemical properties, in most cases attributable to single subspecialized domains. Here a thorough review of the matter is presented, with a privileged look at the pathogenic changes of AIRE that interfere with such properties and lead to the impairment in its chief function.

Regulation of human autoimmune regulator (AIRE) gene translation by miR-220b

Although mutations of autoimmune regulator (AIRE) gene are responsible for autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), presenting a wide spectrum of many characteristic and non-characteristic clinical features, some patients lack AIRE gene mutations. Therefore, something other than a mutation, such as dysregulation of AIRE gene, may be a causal factor for APECED or its related diseases. However, regulatory mechanisms for AIRE gene expression and/or translation have still remained elusive. We found that IL-2-stimulated CD4(+) T (IL-2T) cells showed a high expression of AIRE gene, but very low AIRE protein production, while Epstein-Barr virus-transformed B (EBV-B) cells express both AIRE gene and AIRE protein. By using microarray analysis, we could identify miR-220b as a possible regulatory mechanism for AIRE gene translation in IL-2T cells. Here we report that miR-220b significantly reduced the expression of AIRE protein in AIRE gene with 3'UTR region transfected 293T cells, whereas no alteration of AIRE protein production was observed in the open reading frame of AIRE gene alone transfected cells. In addition, anti-miR-220b reversed the inhibitory function of miR-220b for the expression of AIRE protein in AIRE gene with 3'UTR region transfected cells. Moreover, when AIRE gene transfected cells with mutated 3'UTR were transfected with miR-220b, no reduction of AIRE protein production was observed. Taken together, it was concluded that miR-220b inhibited the AIRE gene translation through the 3'UTR region of AIRE gene, indicating that miR-220b could serve as a regulator for human AIRE gene translation.

APECED: A Paradigm of Complex Interactions between Genetic Background and Susceptibility Factors

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare autosomal recessive disease, caused by mutations of a single gene named Autoimmune regulator gene (AIRE) which results in a failure of T-cell tolerance. Central tolerance takes place within the thymus and represents the mechanism by which potentially auto-reactive T-cells are eliminated through the negative selection process. The expression of tissue-specific antigens (TSAs) by medullary thymic epithelial cells (mTECs) in the thymus is a key process in the central tolerance and is driven by the protein encoded by AIRE gene, the transcription factor autoimmune regulator (AIRE). A failure in this process caused by AIRE mutations is thought to be responsible of the systemic autoimmune reactions of APECED. APECED is characterized by several autoimmune endocrine and non-endocrine manifestations and the phenotype is often complex. Although APECED is the paradigm of a monogenic autoimmune disorder, it is characterized by a wide variability of the clinical expression even between siblings with the same genotype, thus implying that additional mechanisms, other than the failure of Aire function, are involved in the pathogenesis of the disease. Unraveling open issues of the molecular basis of APECED, will help improve diagnosis, management, and therapeutical strategies of this complex disease.