Project description:B-cell leukemia 11b (BCL11B) is a transcription factor known as an essential regulator of T lymphocytes and neuronal development during embryogenesis. A genome-wide association study (GWAS) showed that a gene desert region downstream of BCL11B, known to function as a BCL11B enhancer, harbors single nucleotide polymorphisms (SNPs) associated with increased arterial stiffness. However, a role for BCL11B in the adult cardiovascular system is unknown. Based on these human findings, we sought to examine the relation between BCL11B and arterial function. Here we report that BCL11B is expressed in the vascular smooth muscle (VSM) where it regulates vascular stiffness. RNA sequencing of aortas from WT and Bcl11b null mice (BSMKO) identified the cyclic guanosine monophosphate (cGMP)-protein kinase G (PKG) as the most significant differentially regulated signaling pathway in BSMKO compared to WT mice. BSMKO aortas showed decreased levels of PKG1, increased levels of Ca++-calmodulin-dependent serine/threonine phosphatase calcineurin (PP2B) and their common phosphorylation target, vasodilator-stimulated phosphoprotein (pVASPS239), a regulator of cytoskeletal actin rearrangements. Decreased pVASPS239 in BSMKO aortas was associated with increased actin polymerization (F/G actin ratio). Functionally, aortic force, stress, wall tension and stiffness, measured ex vivo in organ baths, were increased in BSMKO aortas, and BSMKO mice had increased pulse wave velocity, the in vivo index of arterial stiffness. Despite having no effect on blood pressure or microalbuminuria, increased arterial stiffness in BSMKO mice was associated with increased incidence of cerebral microbleeds compared to age-matched WT littermates. In conclusion, we have identified VSM BCL11B as a crucial regulator of aortic smooth muscle function and a potential therapeutic target for vascular stiffness.
Project description:Transcriptional profiling of mouse iNKT cells comparing wild type and Bcl11b deficient cell. The mice were treated with 4 μg of α-galactosylceramide. Goal was to determine the effects of transcription factor Bcl11b removal in iNKT cells. Intraperitoneal treatment with 4 μg of α-Galactosylceramide. Two pair of wild type (BCL11b F/F Vα14 transgenic) and Knock out (BCL11b F/F PLZF-Cre Vα14 transgenic)) mice were treated. Lymphocytes from spleen and liver were enriched and stain with PBS-57 Loaded CD1d tetramer. Pure iNKT cells were collected through cell sorter.
Project description:expression profile in Bcl11b-deficient Treg cells versus wild type Treg cells Treg cells sorted from Bcl11bF/F/Cd4Cre/Foxp3-GFP+ mice and wild type Foxp3-GFP+ mice Treg cells sorted from Bcl11bF/F/Foxp3Cre mice and wild type mice RNA extracted from sorted Bcl11b-deficient Foxp3-GFP Treg cells form Bcl11bF/F/Cd4Cre/Foxp3-GFP+ mice and wild type Foxp3-GFP Treg cells; expression profile by microarray analysis RNA extracted from sorted Bcl11b-deficient Treg cells form Bcl11bF/F/Foxp3Cre mice and wild type Treg cells; expression profile by microarray analysis
Project description:Transcriptional profiling of mouse iNKT cells comparing wild type and Bcl11b deficient cell. The mice were treated with 4 μg of α-galactosylceramide. Goal was to determine the effects of transcription factor Bcl11b removal in iNKT cells.
Project description:Epigenetic landscapes can provide insight into regulation of gene expression and cellular diversity. Here, we examined the transcriptional and epigenetic profiles of seven human blood NK cell populations, including adaptive NK cells. The BCL11B gene, encoding a transcription factor (TF) essential for T cell development and function, was the most extensively regulated, with expression increasing throughout NK cell differentiation. Several Bcl11b-regulated genes associated with T cell-signaling were specifically expressed in adaptive NK cell subsets. Regulatory networks revealed reciprocal regulation at distinct stages of NK cell differentiation, with Bcl11b repressing RUNX2 and ZBTB16 in canonical and adaptive NK cells, respectively. A critical role for Bcl11b in driving NK cell differentiation was corroborated in BCL11B mutated patients and by ectopic Bcl11b expression. Moreover, Bcl11b was required for adaptive NK cell responses in a murine CMV model, supporting expansion of these cells. Together, we define the TF regulatory circuitry of human NK cells and uncover a critical role for Bcl11b in promoting NK cell differentiation and function.
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:The transcription factor (TF) networks that regulate the differentiation of resident versus circulating memory CD8+ T cells are incompletely understood. Here we show that the TF Bcl11b restricts gut resident memory (Trm) cell differentiation, while promoting splenic T central memory (Tcm) and effector memory (Tem) cell differentiation. The reduction of Bcl11b-deficient splenic Tcm and Tem cells was not due to major alterations in their programs, but rather due to the increased homing of their precursors to the small intestine. However, Bcl11b-deficient resident memory precursor cells upregulated residency program, including the TFs Ahr and Prdm1 (encoding Blimp1), and downregulated Tcf7, which restricts the residency program and promotes tissue egress. Bcl11b directly bound at Ahr and Prdm1, as well as at Tcf7 genes. Abrogating Ahr and Prdm1, or restoration of Tcf7 expression in Bcl11b-deficient cells led to partial correction of the excessive resident memory cell differentiation. Functionally, Bcl11b-deficient memory CD8+ T cells had an impaired recall response, but anti-tumor immunity was increased in adoptive cell therapy. Bcl11b also repressed the residency program in human CD8+ T cells and human Bcl11b low tumor-infiltrating lymphocytes showed increased residency gene expression. Thus, Bcl11b plays a critical role in balancing the circulating and tissue residency programs and reveals a potential novel target for cancer immunotherapies.