Disorders of immune dysregulation
Gene: AMFR
Single case report of 3-year-old boy in whom varicella followed a complicated course with thrombocytopenia, haemorrhagic and necrotic lesions, pneumonitis, and intermittent encephalopathy. HLH was the working diagnosis. Although the clinical condition improved, longstanding hemophagocytosis followed despite therapy.
Rare monoallelic variant in autocrine motility factor receptor (AMFR) identified. AMFR encodes a ubiquitin ligase involved in innate cytosolic DNA sensing and interferon (IFN) production through the cyclic GMP-AMP synthase-stimulator of IFN genes (cGAS-STING) pathway.
Peripheral blood mononuclear cells (PBMCs) from the patient exhibited impaired signaling downstream of STING in response dsDNA and 2'3'-cGAMP, agonists of cGAS and STING, respectively, and fibroblasts from the patient showed impaired type I IFN responses and significantly increased VZV replication. Overexpression of the variant AMFR R594C resulted in decreased K27-linked STING ubiquitination compared to WT AMFR. Moreover, ImageStream technology revealed reduced STING trafficking from ER to Golgi in cells expressing the patient AMFR R594C variant. This was supported by a dose-dependent dominant negative effect of expression of the patient AMFR variant as measured by IFN-β reporter gene assay. Finally, lentiviral transduction with WT AMFR partially reconstituted 2'3'-cGAMP-induced STING-mediated signaling and ISG expression in patient PBMCs. This work links defective AMFR-STING signaling to severe VZV disease and hyperinflammation and suggests a direct role for cGAS-STING in the control of viral infections in humans.
Sources: Expert ReviewCreated: 4 Aug 2025, 7:49 a.m.
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
Inborn error of immunity, MONDO:0003778, AMFR-related
Publications
Gene: amfr has been classified as Red List (Low Evidence).
gene: AMFR was added gene: AMFR was added to Disorders of immune dysregulation. Sources: Expert Review Mode of inheritance for gene: AMFR was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for gene: AMFR were set to 38277122 Phenotypes for gene: AMFR were set to Inborn error of immunity, MONDO:0003778, AMFR-related Review for gene: AMFR was set to RED