Project description:<p>We describe four patients from two unrelated families of different ethnicities who had primary immunodeficiency predominantly manifesting as susceptibility to EBV-related diseases. We performed whole exome sequencing (P1 and P2 from family 1) or whole genome sequencing (P4 and both parents from family 2) in those two families and identified homozygous frameshift or in-frame deletions in CD70 in these patients which abolished either CD70 surface expression or binding to its counter structure CD27. Sanger sequencing identified the same homozygous <i>CD70</i> mutation in P3, which is not included in the dbGaP submission. Autosomal recessive CD70 deficiency is a novel cause of combined immunodeficiency and EBV-associated diseases, reminiscent of CD27 deficiency.</p>
Project description:The autosomal recessive immuno-osseus dysplasia spondyloenchondrodysplasia (SPENCD) is characterised by the variable combination of metaphyseal and vertebral bone lesions, immune dysfunction with features of both autoimmunity and immunodeficiency, and neurological involvement including developmental delay and spasticity with intracranial calcification and leukodystrophy. This transcription profiling study of blood compared four patients to two control subjects. A deficiency of ACP5 encoding tartrate resistant acid phosphatase (TRAP) was found to cause this skeletal dysplasia demonstrating a type I interferon signature with autoimmunity.
Project description:<p>To define a genetic syndrome of combined immunodeficiency, severe autoimmunity, and developmental delay, 4 patients from two families who had similar syndromic features were studied. To identify disease-causing mutations, we performed whole exome sequencing for one patient and her healthy parent from Family 1 and also for one patient from Family 2. Disease segregated with novel autosomal recessive mutations in a single gene, tripeptidyl-peptidase II (<i>TPP2</i>) gene. The result defines a new human metabolic immunodeficiency.</p>
Project description:Signal-transducer-and-activator-of-transcription-3 (STAT3) is a central regulator of immune homeostasis. STAT3 levels are strictly controlled and STAT3 impairment contributes to several diseases including the monogenic autosomal-dominant hyper-IgE syndrome (AD-HIES). We investigated patients of four consanguineous families with an autosomal-recessive disorder resembling the phenotype of AD-HIES, with symptoms of immunodeficiency, recurrent infections, skeletal abnormalities, and elevated IgE. Patients presented with reduced STAT3 expression and diminished Th17 cell numbers, in absence of STAT3 mutations. We identified homozygous nonsense mutations in ZNF341, encoding a zinc-finger transcription factor. Wildtype-ZNF341 bound to and activated the STAT3 promoter, whereas the mutant variants showed impaired transcriptional activation, partly due to nuclear translocation failure. In summary, nonsense mutations in ZNF341 account for the STAT3-like phenotype in four autosomal-recessive kindred. Thus, ZNF341 is a previously unrecognized regulator of immune homeostasis.
