Project description:TFRC, also known as CD71, regulates the uptake of transferrin-bound iron into cells through receptor-mediated endocytosis. In a patient with a combined immunodeficiency, we identified a homozygous missense mutation in TFRC gene leading to R22W amino acid change in the cytoplasmic tail of the receptor. This mutation impairs the endocytosis of TFRC, which results in profound aberrations in the immune system.
2024-01-31 | GSE243237 | GEO
Project description:Gene Mutation Causes a Syndrome of Combined Immunodeficiency
Project description:the same population of EPCs was detected in bladder cancer patients. The EPCs, whose function could be reversed via anti-CD71 treatment, were induced by the circRNA TFRC (circular RNA derived from the transferrin receptor mRNA; cTFRC) in bladder cancer exosomes.
Project description:We investigated the ability of transferrin receptor1 (TfRc) knockout cells to populate different domains of the developing kidney by using a chimeric approach. The TfRc cells developed into all segments of the developing nephron, but there was a relative exclusion from the ureteric bud and a positive bias towards the stromal compartment. Here we conducted a microarray analysis of differential gene expression between TfRc deficient and wild type (wt) cells in chimeric embryonic kidneys derived from embryos created by blastocyst injection of wt blastocysts with TfRc-/- green fluorescent protein-expressing (GFP+) embryonic stem cells. Experiment Overall Design: Following blastocyst injection of 3-5 TfRc-/- GFP+ embryonic stem cells in wt blstocysts, we harvested the chimeric kidney at day E15.5 and separated the TfRc-/- GFP+ cell population from wt GFP- cell population by using fluorescence activated cell sorting. Biotinlyated cRNA was prepared from the isolated cells and hybridized to Mouse Genome 430 2.0 Arrays (Affymetrix) according to standard protocols.
Project description:An IRF4 de novo mutation affecting the DNA binding domain of encoded IRF4 protein (mutDBD) was identified in a patient presenting with combined immunodeficiency. The patient exhibited profound susceptibility to opportunistic infections notably Pneumocystis jirovecii and humoral immunodeficiency caused by a failure of terminal B cell differentiation. A heterozygous IRF4 missense variant resulting in a phenylalanine-to-leucine replacement within the interferon activation domain of the encoded IRF4 protein (mutIAD) was identified in three patients from a multigenerational family suffering from a novel autosomal dominant disease predominantly presenting as a hypogammaglobulinemia with recurrent infections. In this experiment we aimed to investigate the effect of the two different mutations on IRF4 genomic binding.
Project description:Background: Severe combined immunodeficiency (SCID) is characterized by arrested T lymphocyte production and B lymphocyte dysfunction, resulting in life-threatening infections. Early diagnosis of SCID through population-based newborn screening (NBS) optimizes clinical management and outcomes, and also permits identification of previously unknown factors essential for human lymphocyte development. Methods: SCID was detected, prior to onset of infections, by NBS of T cell receptor excision circles, a biomarker for thymic output. Upon confirmation, the affected baby was treated by allogeneic hematopoietic cell transplantation (HCT). The genetic cause was sought by exome sequencing of the patient and parents, followed by functional analysis of a prioritized candidate gene using human hematopoietic stem cells (HSC) and zebrafish embryos. Results: An infant with leaky SCID, craniofacial and dermal abnormalities, and absent corpus callosum had his immune deficit fully corrected by HCT. Exome sequencing revealed a heterozygous, de novo, missense mutation pN441K in BCL11B. The mutant Bcl11b protein had dominant negative activity, abrogating the ability of wild type Bcl11b to bind DNA, arresting T cell lineage development and disrupting HSC migration, revealing a novel function of Bcl11b. The patientâs defects, recapitulated in Bcl11b-deficient zebrafish, were reversed by ectopic expression of intact, but not mutant, human BCL11B. Conclusions: Newborn screening facilitated treatment and identification of a novel etiology for human SCID. Coupling exome sequencing with candidate gene evaluation in human HSC and in zebrafish revealed that a constitutional BCL11B mutation causes human multisystem anomalies with SCID, while also revealing a novel, pre-thymic role for Bcl11b in hematopoietic progenitors. 3 samples were analyzed in duplicate, Sample 1 was human HSC transduced with GFP only lentivirus which served as controls, Sample 2 was human HSC transduced with lentivirus expressing FLAG-tagged WT BCL11B and GFP, Sample 3 was human HSC transduced with lentivirus expressing FLAG-tagged mutant BCL11B and GFP
Project description:We investigated the ability of transferrin receptor1 (TfRc) knockout cells to populate different domains of the developing kidney by using a chimeric approach. The TfRc cells developed into all segments of the developing nephron, but there was a relative exclusion from the ureteric bud and a positive bias towards the stromal compartment. Here we conducted a microarray analysis of differential gene expression between TfRc deficient and wild type (wt) cells in chimeric embryonic kidneys derived from embryos created by blastocyst injection of wt blastocysts with TfRc-/- green fluorescent protein-expressing (GFP+) embryonic stem cells. Keywords: cell type comparison, genetic modification, iron signaling
Project description:This study reports two unrelated patients with a combined immunodeficiency. Whole-exome sequencing of both patients, their healthy parents and siblings identified a single de novo missense variant in ITPR3 (NM_002224.3:c.7570C>T, p.Arg2524Cys) in both index cases. While the mRNA level in patients remained the same as in healthy siblings and controls, the level of protein expression was diminished. It was also shown that the ITPR3 heterozygous p.Arg2524Cys mutation impairs calcium flux function in dermal fibroblast of one patient and in a knock-in Jurkat T cell line. Two additional patients with related phenotypes and the same mutation were further identified and described in the study. The present dataset corresponds to the RNAseq performed on PBMC of patient 2 of the study and healthy controls.