[Advance of research on 22q11.2 deletion syndrome].

22q11.2 deletion syndrome (22q11.2DS) is the most common chromosomal microdeletion disorder. Its phenotype is highly variable with incomplete penetrance. 22q11.2DS is a rare disease, and the research progress is relatively slow, which has restricted its treatment and intervention. In recent years, much progress has been made in the pathogenic mechanism and genome-wide association study of 22q11.2DS. In this review, the pathogenesis of 22q11.2DS was summarized. Thereafter, the molecular and pathological mechanisms of TBX1 and DGCR8 genes were clarified. Finally, factors affecting the penetrance of cardiac and immune system phenotypes were reviewed. This review may enhance the understanding of 22q11.2DS and has important clinical implications on the prenatal diagnosis, genetic counseling, treatment and intervention of this disease.

Genomic profiles and clinical presentation of chordoma.

Chordoma is a rare bone cancer with variable clinical outcomes. Here, we recruited 184 sporadic chordoma patients from the US and Canada and collected their clinical and treatment data. The average age at diagnosis was 45.5 years (Range 5-78) and the chordoma site distribution was 49.2% clivus, 26.2% spinal, and 24.0% sacral. Most patients (97.5%) received surgery as the primary treatment, among whom 85.3% also received additional treatment. Except for the most prevalent cancers like prostate, lung, breast, and skin cancer, there was no discernible enrichment for any specific cancer type among patients or their family members. Among a subset of patients (N = 70) with tumor materials, we conducted omics analyses and obtained targeted panel sequencing and SNP array genotyping data for 51 and 49 patients, respectively. The most recurrent somatic driver mutations included PIK3CA (12%), followed by chromatin remodeling genes PBRM1 and SETD2. Amplification of the 6q27 region, containing the chordoma susceptibility gene TBXT, was detected in eight patients (16.3%). Clival patients appeared to be less likely to carry driver gene mutations, chromosome arm level deletion events (e.g., 5p, 5p, and 9p), or 6q27 amplification compared to sacral patients. After adjusting for age, sex, tumor site, and additional treatment, patients with somatic deletions of 14q (OR = 13.73, 95% CI 1.96-96.02, P = 0.008) and 18p (OR = 13.68, 95% CI 1.77-105.89, P = 0.012) were more likely to have persistent chordoma. The study highlights genomic heterogeneity in chordoma, potentially linked to location and clinical progression.

Transcriptional regulation of the postnatal cardiac conduction system heterogeneity.

The cardiac conduction system (CCS) is a network of specialized cardiomyocytes that coordinates electrical impulse generation and propagation for synchronized heart contractions. Although the components of the CCS, including the sinoatrial node, atrioventricular node, His bundle, bundle branches, and Purkinje fibers, were anatomically discovered more than 100 years ago, their molecular constituents and regulatory mechanisms remain incompletely understood. Here, we demonstrate the transcriptomic landscape of the postnatal mouse CCS at a single-cell resolution with spatial information. Integration of single-cell and spatial transcriptomics uncover region-specific markers and zonation patterns of expression. Network inference shows heterogeneous gene regulatory networks across the CCS. Notably, region-specific gene regulation is recapitulated in vitro using neonatal mouse atrial and ventricular myocytes overexpressing CCS-specific transcription factors, Tbx3 and/or Irx3. This finding is supported by ATAC-seq of different CCS regions, Tbx3 ChIP-seq, and Irx motifs. Overall, this study provides comprehensive molecular profiles of the postnatal CCS and elucidates gene regulatory mechanisms contributing to its heterogeneity.

Concurrent of compound heterozygous variant of a novel in-frame deletion and the common hypomorphic haplotype in TBX6 and inherited 17q12 microdeletion in a fetus.

BACKGROUND: TBX6, a member of the T-box gene family, encodes the transcription factor box 6 that is critical for somite segmentation in vertebrates. It is known that the compound heterozygosity of disruptive variants in trans with a common hypomorphic risk haplotype (T-C-A) in the TBX6 gene contribute to 10% of congenital scoliosis (CS) cases. The deletion of chromosome 17q12 is a rare cytogenetic abnormality, which often leads to renal cysts and diabetes mellitus. However, the affected individuals often exhibit clinical heterogeneity and incomplete penetrance. METHODS: We here present a Chinese fetus who was shown to have CS by ultrasound examination at 17 weeks of gestation. Trio whole-exome sequencing (WES) was performed to investigate the underlying genetic defects of the fetus. In vitro functional experiments, including western-blotting and luciferase transactivation assay, were performed to determine the pathogenicity of the novel variant of TBX6. RESULTS: WES revealed the fetus harbored a compound heterozygous variant of c.338_340del (p.Ile113del) and the common hypomorphic risk haplotype of the TBX6 gene. In vitro functional study showed the p.Ile113del variant had no impact on TBX6 expression, but almost led to complete loss of its transcriptional activity. In addition, we identified a 1.85 Mb deletion on 17q12 region in the fetus and the mother. Though there is currently no clinical phenotype associated with this copy number variation in the fetus, it can explain multiple renal cysts in the pregnant woman. CONCLUSIONS: This study is the first to report a Chinese fetus with a single amino acid deletion variant and a T-C-A haplotype of TBX6. The clinical heterogeneity of 17q12 microdeletion poses significant challenges for prenatal genetic counseling. Our results once again suggest the complexity of prenatal genetic diagnosis.

[Pituitary Crooke cell neuroendocrine tumor of adrenocorticotropic hormone differentiation-specific transcription factor lineage: a clinicopathological analysis of six cases].

Objective: To investigate the clinicopathological features of Crooke cell tumor of adrenocorticotropic hormone differentiation specific transcription factor (TPIT, also known as transcription factor 19, TBX19) lineage neuroendocrine tumors. Methods: Six cases of Crooke cell tumor diagnosed at the First Affiliated Hospital of University of Science and Technology of China, Hefei, China from October 2019 to October 2023 were collected. The clinical and pathological features of these cases were analyzed. Results: Among the six cases, one was male and five were female, with ages ranging from 26 to 75 years, and an average age of 44 years. All tumors occurred within the sella turcica. Clinical presentations included visual impairment in two cases, menstrual disorders in one case, Cushing's syndrome in one case, headache in one case, and one asymptomatic case discovered during a physical examination. Preoperative serum analyses revealed elevated levels of cortisol and adrenocorticotropic hormones in two cases, elevated cortisol in two cases, elevated adrenocorticotropic hormone in one case, and one case with a mild increase in prolactin due to the pituitary stalk effect. Magnetic resonance imaging revealed uneven enhancement of masses with maximum diameters ranging from 1.7 to 3.2 cm, all identified as macroadenomas. Microscopically, tumor cells exhibited irregular polygonal shapes, solid sheets, or pseudo-papillary arrangements around blood vessels. The cell nuclei were eccentric or centrally located, varying in size, with abundant cytoplasm. Some tumor cells showed perinuclear halo. Immunohistochemistry demonstrated diffuse strong positivity for TPIT in five cases, focal weak positivity for TPIT in one case, diffuse strong positivity for adrenocorticotropic hormone in all cases, and faint staining around the nuclei in a few cells. CK8/18 showed a strong positive ring pattern in more than 50% of tumor cells, focal weak positive expression of p53, and the Ki-67 positive index ranged 1%-5%. Periodic acid-Schiff staining revealed positive cytoplasm and negative perinuclear areas. Conclusions: Crooke cell tumor is a rare type of pituitary neuroendocrine tumors. Its pathological characteristics include a distinctive perinuclear clear zone and immunohistochemical markers, such as CK8/18 exhibiting a ring or halo pattern. This entity represents a high-risk subtype among pituitary neuroendocrine tumors, displaying a high risk of invasion and a propensity for recurrence. Accurate diagnosis is crucial for the postoperative follow-up and multimodal treatment planning.

Construction and validation of prognostic signature for transcription factors regulating T cell exhaustion in hepatocellular carcinoma.

In the tumor microenvironment (TME), CD8+ T cells showed stage exhaustion due to the continuous stimulation of tumor antigens. To evaluate the status of CD8+ T cells and reverse the exhaustion is the key to evaluate the prognosis and therapeutic effect of tumor patients. The aim of this study was to establish a prognostic signature that could effectively predict prognosis and response to immunotherapy in patients with hepatocellular carcinoma (HCC). We used univariate Cox analysis to obtain transcription factors associated with CD8+ T cell exhaustion from The Cancer Genome Atlas dataset. Then, the prognostic signature for transcription factors basic leucine zipper ATF-like transcription factor, Eomesodermin, and T-box protein 21 regulating T cell exhaustion was constructed using LASSO Cox regression. The relative expression levels of the mRNA of the 3 transcription factors were detected by reverse transcription-quantitative polymerase chain reaction in 23 pairs of HCC and paracancer tissues, and verified internally in The Cancer Genome Atlas dataset and externally in the International Cancer Genome Consortium dataset. Cox regression analysis showed that risk score was an independent prognostic variable. The overall survival of the high-risk group was significantly lower than that of the low-risk group. The low-risk group had higher immune scores, matrix scores, and ESTIMATE scores, and significantly increased expression levels of most immune checkpoint genes in the low-risk group. Therefore, patients with lower risk scores benefit more from immunotherapy. The combination of the 3 transcription factors can evaluate the exhaustion state of CD8+ T cells in the TME, laying a foundation for evaluating the TME and immunotherapy efficacy in patients with HCC.

Diversity of group 1 innate lymphoid cells in human tissues.

Group 1 innate lymphoid cells (ILC1s) are cytotoxic and interferon gamma-producing lymphocytes lacking antigen-specific receptors, which include ILC1s and natural killer (NK) cells. In mice, ILC1s differ from NK cells, as they develop independently of the NK-specifying transcription factor EOMES, while requiring the repressor ZFP683 (ZNF683 in humans) for tissue residency. Here we identify highly variable ILC1 subtypes across tissues through investigation of human ILC1 diversity by single-cell RNA sequencing and flow cytometry. The intestinal epithelium contained abundant mature EOMES- ILC1s expressing PRDM1 rather than ZNF683, alongside a few immature TCF7+PRDM1- ILC1s. Other tissues harbored NK cells expressing ZNF683 and EOMES transcripts; however, EOMES protein content was variable. These ZNF683+ NK cells are tissue-imprinted NK cells phenotypically resembling ILC1s. The tissue ILC1-NK spectrum also encompassed conventional NK cells and NK cells distinguished by PTGDS expression. These findings establish a foundation for evaluating phenotypic and functional changes within the NK-ILC1 spectrum in diseases.

Effect of Intramyocardial Administration of Baculovirus Encoding the Transcription Factor Tbx20 in Sheep With Experimental Acute Myocardial Infarction.

BACKGROUND: Gene therapy has been proposed as a strategy to induce cardiac regeneration following acute myocardial infarction (AMI). Given that Tbx20, a transcription factor of the T-box subfamily, stimulates cell proliferation and angiogenesis, we designed a baculovirus overexpressing Tbx20 (Bv-Tbx20) and evaluated its effects in cultured cardiomyocytes and in an ovine model of AMI. METHODS AND RESULTS: Cell proliferation and angiogenesis were measured in cardiomyocytes transduced with Bv-Tbx20 or Bv-Null (control). Subsequently, in sheep with AMI, Bv-Tbx20 or Bv-Null was injected in the infarct border. Cardiomyocyte cell cycle activity, angioarteriogenesis, left ventricular function, and infarct size were assessed. Cardiomyocytes transduced with BvTbx20 increased cell proliferation, cell cycle regulatory and angiogenic gene expression, and tubulogenesis. At 7 days posttreatment, sheep treated with Bv-Tbx20 showed increased Tbx20, promitotic and angiogenic gene expression, decreased levels of P21, increased Ki67- (17.09±5.73 versus 7.77±7.24 cardiomyocytes/mm2, P<0.05) and PHH3 (phospho-histone H3)-labeled cardiomyocytes (10.10±3.51 versus 5.23±2.87 cardiomyocytes/mm2, P<0.05), and increased capillary (2302.68±353.58 versus 1694.52±211.36 capillaries/mm2, P<0.001) and arteriolar (146.95±53.14 versus 84.06±16.84 arterioles/mm2, P<0.05) densities. At 30 days, Bv-Tbx20 decreased infarct size (9.89±1.92% versus 12.62±1.33%, P<0.05) and slightly improved left ventricular function. Baculoviral gene transfer-mediated Tbx20 overexpression exerted angiogenic and cardiomyogenic effects in vitro. CONCLUSIONS: In sheep with AMI, Bv-Tbx20 induced angioarteriogenesis, cardiomyocyte cell cycle activity, infarct size limitation, and a slight recovery of left ventricular function, suggesting that Bv-Tbx20 gene therapy may contribute to cardiac regeneration following AMI.

Deep brain stimulation of the Tbr1-deficient mouse model of autism spectrum disorder at the basolateral amygdala alters amygdalar connectivity, whole-brain synchronization, and social behaviors.

Autism spectrum disorders (ASDs) are considered neural dysconnectivity syndromes. To better understand ASD and uncover potential treatments, it is imperative to know and dissect the connectivity deficits under conditions of autism. Here, we apply a whole-brain immunostaining and quantification platform to demonstrate impaired structural and functional connectivity and aberrant whole-brain synchronization in a Tbr1+/- autism mouse model. We express a channelrhodopsin variant oChIEF fused with Citrine at the basolateral amygdala (BLA) to outline the axonal projections of BLA neurons. By activating the BLA under blue light theta-burst stimulation (TBS), we then evaluate the effect of BLA activation on C-FOS expression at a whole brain level to represent neural activity. We show that Tbr1 haploinsufficiency almost completely disrupts contralateral BLA axonal projections and results in mistargeting in both ipsilateral and contralateral hemispheres, thereby globally altering BLA functional connectivity. Based on correlated C-FOS expression among brain regions, we further show that Tbr1 deficiency severely disrupts whole-brain synchronization in the absence of salient stimulation. Tbr1+/- and wild-type (WT) mice exhibit opposing responses to TBS-induced amygdalar activation, reducing synchronization in WT mice but enhancing it in Tbr1+/- mice. Whole-brain modular organization and intermodule connectivity are also affected by Tbr1 deficiency and amygdalar activation. Following BLA activation by TBS, the synchronizations of the whole brain and the default mode network, a specific subnetwork highly relevant to ASD, are enhanced in Tbr1+/- mice, implying a potential ameliorating effect of amygdalar stimulation on brain function. Indeed, TBS-mediated BLA activation increases nose-to-nose social interactions of Tbr1+/- mice, strengthening evidence for the role of amygdalar connectivity in social behaviors. Our high-resolution analytical platform reveals the inter- and intrahemispheric connectopathies arising from ASD. Our study emphasizes the defective synchronization at a whole-brain scale caused by Tbr1 deficiency and implies a potential beneficial effect of deep brain stimulation at the amygdala for TBR1-linked autism.

Context-dependent T-BOX transcription factor family: from biology to targeted therapy.

T-BOX factors belong to an evolutionarily conserved family of transcription factors. T-BOX factors not only play key roles in growth and development but are also involved in immunity, cancer initiation, and progression. Moreover, the same T-BOX molecule exhibits different or even opposite effects in various developmental processes and tumor microenvironments. Understanding the multiple roles of context-dependent T-BOX factors in malignancies is vital for uncovering the potential of T-BOX-targeted cancer therapy. We summarize the physiological roles of T-BOX factors in different developmental processes and their pathological roles observed when their expression is dysregulated. We also discuss their regulatory roles in tumor immune microenvironment (TIME) and the newly arising questions that remain unresolved. This review will help in systematically and comprehensively understanding the vital role of the T-BOX transcription factor family in tumor physiology, pathology, and immunity. The intention is to provide valuable information to support the development of T-BOX-targeted therapy.

Dietary vitamin D3 supplementation enhances splenic NK cell activity in healthy and diabetic male mice.

Type 2 diabetes mellitus negatively affects the immune system, resulting in reduced natural killer (NK) cell activity. Vitamin D has been shown to regulate innate and adaptive immune cells. However, the effects of vitamin D on NK cells remain inconclusive, especially in the context of diabetes. We hypothesized that dietary vitamin D3 supplementation can enhance NK cell activity in diabetic mice. Therefore, we investigated the effects of dietary vitamin D3 on NK cell activity in control and diabetic mice and explored the mechanisms of NK cell activity modulation by vitamin D3. Control (CON) and diabetic mice (db/db) were randomly divided into 2 groups, then fed either a control diet (948 IU vitamin D3/kg diet, vDC) or a diet supplemented with vitamin D3 (9,477 IU vitamin D3/kg diet, vDS) for 8 weeks. Diabetic mice exhibited lower NK cell activity than control mice. The vDS group had significantly higher NK cell activity than the vDC group in both control and diabetic mice. The vDS group had a higher percentage of CD11b single-positive NK cells than the vDC group (CON-vDS 34%; db/db-vDS 30%; CON-vDC 27%; db/db-vDC 22%). The intracellular expression of splenic TGF-ß was significantly higher in the db/db group than in the CON group. Overall, vDS group had higher Bcl2 and Tbx21 mRNA expressions than the vDC group. In conclusion, the present study shows that NK cell activity is impaired under diabetic conditions, possibly due to the reduced percentage of mature NK cells. Moreover, NK activity is enhanced by dietary supplementation in both control and diabetic mice that may be associated with changes in the proportion of mature NK cells.

Dedifferentiation-like reprogramming of degenerative nucleus pulposus cells into notochordal-like cells by defined factors.

The extensive degeneration of functional somatic cells and the depletion of endogenous stem/progenitor populations present significant challenges to tissue regeneration in degenerative diseases. Currently, a cellular reprogramming approach enabling directly generating corresponding progenitor populations from degenerative somatic cells remains elusive. The present study focused on intervertebral disc degeneration (IVDD) and identified a three-factor combination (OCT4, FOXA2, TBXT [OFT]) that could induce the dedifferentiation-like reprogramming of degenerative nucleus pulposus cells (dNPCs) toward induced notochordal-like cells (iNCs). Single-cell transcriptomics dissected the transitions of cell identity during reprogramming. Further, OCT4 was found to directly interact with bromodomain PHD-finger transcription factor to remodel the chromatin during the early phases, which was crucial for initiating this dedifferentiation-like reprogramming. In rat models, intradiscal injection of adeno-associated virus carrying OFT generated iNCs from in situ dNPCs and reversed IVDD. These results collectively present a proof-of-concept for dedifferentiation-like reprogramming of degenerated somatic cells into corresponding progenitors through the development of a factor-based strategy, providing a promising approach for regeneration in degenerative disc diseases.

Engrailed transcription factors direct excitatory cerebellar neuron diversity and survival.

The neurons of the three cerebellar nuclei (CN) are the primary output neurons of the cerebellum. The excitatory neurons (e) of the medial (m) CN (eCNm) were recently divided into molecularly defined subdomains in the adult; however, how they are established during development is not known. We define molecular subdomains of the mouse embryonic eCNm using single-cell RNA-sequencing and spatial expression analysis, showing that they evolve during embryogenesis to prefigure the adult. Furthermore, eCNm are transcriptionally divergent from cells in the other nuclei by embryonic day 14.5. We previously showed that loss of the homeobox genes En1 and En2 leads to loss of approximately half of the embryonic eCNm. We demonstrate that mutation of En1/2 in the embryonic eCNm results in death of specific posterior eCNm molecular subdomains and downregulation of TBR2 (EOMES) in an anterior embryonic subdomain, as well as reduced synaptic gene expression. We further reveal a similar function for EN1/2 in mediating TBR2 expression, neuron differentiation and survival in the other excitatory neurons (granule and unipolar brush cells). Thus, our work defines embryonic eCNm molecular diversity and reveals conserved roles for EN1/2 in the cerebellar excitatory neuron lineage.

Overexpression of TBX3 suppresses tumorigenesis in experimental and human cholangiocarcinoma.

TBX3 behaves as a tumor suppressor or oncoprotein across cancer. However, TBX3 function remains undetermined in intrahepatic cholangiocarcinoma (iCCA), a deadly primary liver malignancy with few systemic treatment options. This study sought to investigate the impact of TBX3 on iCCA. We found that overexpression of TBX3 strongly inhibited human iCCA cell growth. In the Akt/FBXW7ΔF mouse iCCA model, overexpression of Tbx3 reduced cholangiocarcinogenesis in vivo, while inducible genetic knockout of Tbx3 accelerated iCCA growth. RNA-seq identified MAD2L1 as a downregulated gene in TBX3-overexpressing cells, and ChIP confirmed that TBX3 binds to the MAD2L1 promoter. CRISPR-mediated knockdown of Mad2l1 significantly reduced the growth of two iCCA models in vivo. Finally, we found that TBX3 expression is upregulated in ~20% of human iCCA samples, and its high expression is associated with less proliferation and better survival. MAD2L1 expression is upregulated in most human iCCA samples and negatively correlated with TBX3 expression. Altogether, our findings suggest that overexpression of TBX3 suppresses CCA progression via repressing MAD2L1 expression.

Formaldehyde exacerbates inflammation and biases T helper cell lineage commitment through IFN-γ/STAT1/T-bet pathway in asthma.

The correlation between formaldehyde (FA) exposure and prevalence of asthma has been widely reported. However, the underlying mechanism is still not fully understood. FA exposure at 2.0 mg/m3 was found to exacerbate asthma in OVA-induced murine models. IFN-γ, the cytokine produced by T helper 1 (Th1) cells, was significantly induced by FA in serum and bronchoalveolar lavage fluid (BALF) of asthmatic mice, which was different from cytokines secreted by other Th cells. The observation was also confirmed by mRNA levels of Th marker genes in CD4+ T cells isolated from BALF. In addition, increased production of IFN-γ and expression of T-bet in Jurkat T cells primed with phorbol ester and phytohaemagglutinin were also observed with 100 µM FA treatment in vitro. Upregulated STAT1 phosphorylation, T-bet expression and IFN-γ production induced by FA was found to be restrained by STAT1 inhibitor fludarabine, indicating that FA promoted Th1 commitment through the autocrine IFN-γ/STAT1/T-bet pathway in asthma. This work not only revealed that FA could bias Th lineage commitment to exacerbate allergic asthma, but also identified the signaling mechanism of FA-induced Th1 differentiation, which may be utilized as the target for development of interfering strategies against FA-induced immune disorders.

TBX3 is essential for establishment of the posterior boundary of anterior genes and upregulation of posterior genes together with HAND2 during the onset of limb bud development.

During limb bud formation, axis polarities are established as evidenced by the spatially restricted expression of key regulator genes. In particular, the mutually antagonistic interaction between the GLI3 repressor and HAND2 results in distinct and non-overlapping anterior-distal Gli3 and posterior Hand2 expression domains. This is a hallmark of the establishment of antero-posterior limb axis polarity, together with spatially restricted expression of homeodomain and other transcriptional regulators. Here, we show that TBX3 is required for establishment of the posterior expression boundary of anterior genes in mouse limb buds. ChIP-seq and differential gene expression analysis of wild-type and mutant limb buds identifies TBX3-specific and shared TBX3-HAND2 target genes. High sensitivity fluorescent whole-mount in situ hybridisation shows that the posterior expression boundaries of anterior genes are positioned by TBX3-mediated repression, which excludes anterior genes such as Gli3, Alx4, Hand1 and Irx3/5 from the posterior limb bud mesenchyme. This exclusion delineates the posterior mesenchymal territory competent to establish the Shh-expressing limb bud organiser. In turn, HAND2 is required for Shh activation and cooperates with TBX3 to upregulate shared posterior identity target genes in early limb buds.

Chordoma: Genetics and Contemporary Management.

Chordomas, arising from notochord remnants, are rare neoplasms with aggressive growth patterns despite their histologically low-grade nature. This review explores their embryological origins, molecular markers like brachyury, and genetic alterations driving pathogenesis. Diagnosis relies on advanced imaging and biopsy confirmation due to overlapping features with chondrosarcoma. The WHO classification distinguishes conventional, dedifferentiated, and poorly differentiated chordomas, each with distinct prognostic implications. Recent genomic analyses uncovered recurrent mutations in PI3K signaling pathways and chromatin remodeling genes, informing prognostic models. Surgery remains the cornerstone of treatment, though adjuvant radiation complements surgical resection. Although chordomas are generally considered refractory to medical therapy, emerging targeted molecular strategies show potential promise in ongoing trials. This review aims to provide a concise yet comprehensive overview of chordomas, guiding clinicians in diagnosis, treatment, and prognostication for improved patient outcomes.

Eomes expression identifies the early bone marrow precursor to classical NK cells.

Natural killer (NK) cells traffic through the blood and mount cytolytic and interferon-γ (IFNγ)-focused responses to intracellular pathogens and tumors. Type 1 innate lymphoid cells (ILC1s) also produce type 1 cytokines but reside in tissues and are not cytotoxic. Whether these differences reflect discrete lineages or distinct states of a common cell type is not understood. Using single-cell RNA sequencing and flow cytometry, we focused on populations of TCF7+ cells that contained precursors for NK cells and ILC1s and identified a subset of bone marrow lineage-negative NK receptor-negative cells that expressed the transcription factor Eomes, termed EomeshiNKneg cells. Transfer of EomeshiNKneg cells into Rag2-/-Il2rg-/- recipients generated functional NK cells capable of preventing metastatic disease. By contrast, transfer of PLZF+ ILC precursors generated a mixture of ILC1s, ILC2s and ILC3s that lacked cytotoxic potential. These findings identified EomeshiNKneg cells as the bone marrow precursor to classical NK cells and demonstrated that the NK and ILC1 lineages diverged early during development.

Plasticity and lineage commitment of individual TH1 cells are determined by stable T-bet expression quantities.

T helper 1 (TH1) cell identity is defined by the expression of the lineage-specifying transcription factor T-bet. Here, we examine the influence of T-bet expression heterogeneity on subset plasticity by leveraging cell sorting of distinct in vivo-differentiated TH1 cells based on their quantitative expression of T-bet and interferon-γ. Heterogeneous T-bet expression states were regulated by virus-induced type I interferons and were stably maintained even after secondary viral infection. Exposed to alternative differentiation signals, the sorted subpopulations exhibited graded levels of plasticity, particularly toward the TH2 lineage: T-bet quantities were inversely correlated with the ability to express the TH2 lineage-specifying transcription factor GATA-3 and TH2 cytokines. Reprogramed TH1 cells acquired graded mixed TH1 + TH2 phenotypes with a hybrid epigenetic landscape. Continuous presence of T-bet in differentiated TH1 cells was essential to ensure TH1 cell stability. Thus, innate cytokine signals regulate TH1 cell plasticity via an individual cell-intrinsic rheostat to enable T cell subset adaptation to subsequent challenges.

Human Genetics of Truncus Arteriosus.

Integrated human genetics and molecular/developmental biology studies have revealed that truncus arteriosus is highly associated with 22q11.2 deletion syndrome. Other congenital malformation syndromes and variants in genes encoding TBX, GATA, and NKX transcription factors and some signaling proteins have also been reported as its etiology.