Heterozygous STAT1 gain-of-function (GOF) mutations result in a combined form of immunodeficiency which is the most common genetic cause of chronic mucocutaneous candidiasis (CMC).
We report a case of CMC/CID in a 10-year-old boy due to a novel mutation in the small ubiquitin molecule (SUMO) consensus site at the C-terminal region of STAT1 leading to gain-of-function by impaired sumoylation.
Heterozygous gain-of-function (GOF) mutations in the cytokine-regulated transcription factor STAT1 (signal transducer and activator of transcription 1) lead to chronic mucocutaneous candidiasis (CMC).
Autosomal dominant STAT1 mutations in humans have been associated with chronic mucocutaneous candidiasis (CMC), as well as with increased susceptibility to herpesvirus infections.
More recently, increasing focus has been on aspects of autoimmunity and autoinflammation playing an important part in many primary immunodeficiency diseases (PID)s, as exemplified by STAT1 gain-of-function causing CMC and autoimmune thyroiditis, as well as a recently described autoinflammatory syndrome with hypogammaglobulinemia and lymphoproliferation as a result of STAT3 gain-of-function.
Signal transducer and activator of transcription 1 (STAT-1) gain-of-function (GOF) mutations cause chronic mucocutaneous candidiasis (CMC), a disease associated with Candida albicans and Staphylococcus aureus infection.
Heterozygous gain-of-function (GOF) mutations in the signal transducer and activator of transcription 1 (STAT1) have increasingly been identified as a genetic cause of autosomal-dominant (AD) chronic mucocutaneous candidiasis (CMC).
Patients with heterozygous STAT1 gain-of-function (GOF) mutations usually present with chronic mucocutaneous candidiasis (CMC) but may also experience bacterial and viral infections, autoimmune manifestations, lymphopenia, cerebral aneurysms, and increased risk to develop tumors.
Patients with <i>STAT1</i> gain-of-function (GOF) mutations also develop CMC and autoimmunity; they exhibit increased STAT1 protein levels at baseline and STAT1 phosphorylation (pSTAT1) upon interferon (IFN)-γ stimulation relative to healthy controls.
Further, the statistical analysis of RNA-seq data with STAT1-deficient epithelial cells and primary T cells from a CMC patient revealed that the R274Q mutation affected gene expression levels of 66 and 76 non-overlapping RefSeq genes, respectively.
STAT1 GOF mutations underlie AD CMC, as well as an unexpectedly wide range of other clinical features, including not only a variety of infectious and autoimmune diseases, but also cerebral aneurysms and carcinomas that confer a poor prognosis.
Recently, gain-of-function (GOF) mutations in the gene encoding signal transducer and activator of transcription 1 (STAT1) have been associated with chronic mucocutaneous candidiasis (CMC).
Reduced STAT3-dependent gene transcription underlies low Th-17 responses in GOF-STAT1CMC, which can be reversed by inhibiting acetylation, offering novel targets for future therapies.
This is the first patient with severe orf in the context of a well-defined genetically identified PID: CMC and inborn error of IL-17 immunity due to a GOF STAT1 mutation.
These findings describe the role of STAT-1 for the induction of trained immunity, and may contribute to the understanding of the differences in susceptibility to infection between CMC and HIES patients.
The two previously reported types of AD MSMD-causing STAT1 mutations are located in the tail segment domain (p.L706S) or in the DNA-binding domain (p.E320Q and p.Q463H), whereas the AD CMC-causing mutations are located in the coiled-coil domain.