IPEX due to an exon 7 skipping FOXP3 mutation with autoimmune diabetes mellitus cured by selective T-Reg cell engraftment

Magg, Thomas; Wiebking, Volker; Conca, Raffaele; Krebs, Stefan; Arens, Stefan; Schmid, Irene; Klein, Christoph; Albert, Michael H. and Hauck, Fabian (2018): IPEX due to an exon 7 skipping FOXP3 mutation with autoimmune diabetes mellitus cured by selective T-Reg cell engraftment. In: Clinical Immunology, Vol. 191: pp. 52-58

Abstract

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is a rare inherited disorder leading to severe organ-specific autoimmunity. IPEX is caused by hemizygous mutations in FOXP3, which codes for a master transcription factor of regulatory T (T-Reg) cell development and function. We describe a four-year-old boy with typical but slightly delayed-onset of IPEX with autoimmune diabetes mellitus, enteropathy, hepatitis and skin disease. We found the unreported FOXP3 splice site mutation c.816 + 2T > A that leads to the loss of leucine-zipper coding exon 7. RNA-Seq revealed that FOXP3 Delta 7 leads to differential expression of FOXP3 regulated genes. After myeloablative conditioning the patient underwent allogeneic HSCT from a matched unrelated donor. HSCT led to the resolution of all IPEX symptoms including insulin requirement despite persisting autoantibody levels. After initial full donor engraftment nearly complete autologous reconstitution was documented, but donor-derived T-Reg cells persisted with a lineage-specific chimerism of > 70% and the patient remained in clinical remission.

• Item Type: Journal article
• Faculties: Medicine; Chemistry and Pharmacy > Department of Biochemistry
• Subjects: 600 Technology > 610 Medicine and health; 500 Science > 540 Chemistry
• ISSN: 1521-6616
• Language: English