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Most tools for analyzing large gene expression datasets, including The Cancer Genome Atlas (TCGA), have focused on analyzing the expression of individual genes or inference of the abundance of specific cell types from whole transcriptome information. While these methods provide useful insights, they can overlook crucial process-based information that may enhance our understanding of cancer biology. In this study, we describe three novel tools incorporated into an online resource; gene set-based analysis of The Cancer Genome Atlas (GS-TCGA). GS-TCGA is designed to enable user-friendly exploration of TCGA data using gene set-based analysis, leveraging gene sets from the Molecular Signatures Database. GS-TCGA includes three unique tools: GS-Surv determines the association between the expression of gene sets and survival in human cancers. Co-correlative gene set enrichment analysis (CC-GSEA) utilizes interpatient heterogeneity in cancer gene expression to infer functions of specific genes based on GSEA of coregulated genes in TCGA. GS-Corr utilizes interpatient heterogeneity in cancer gene expression profiles to identify genes coregulated with the expression of specific gene sets in TCGA. Users are also able to upload custom gene sets for analysis with each tool. These tools empower researchers to perform survival analysis linked to gene set expression, explore the functional implications of gene coexpression, and identify potential gene regulatory mechanisms. [ABSTRACT FROM AUTHOR]

Summary: The inflammatory response to transformed cells forms the cornerstone of natural or therapeutically induced protective immunity to cancer. Regulatory T (Treg) cells are known for their critical role in suppressing inflammation, and therefore can antagonize effective anti‐cancer immune responses. As such, Treg cells can play detrimental roles in tumour progression and in the response to both conventional and immune‐based cancer therapies. Recent advances in our understanding of Treg cells reveal complex niche‐specific regulatory programmes and functions, which are likely to extrapolate to cancer. The regulation of Treg cells is reliant on upstream cues from haematopoietic and non‐immune cells, which dictates their genetic, epigenetic and downstream functional programmes. In this review we will discuss how Treg cells are themselves regulated in normal and transformed tissues, and the implications of this cross talk on tumour growth. [ABSTRACT FROM AUTHOR]

In this issue of Cancer Cell , Espinosa-Carrasco et al. show that the efficacy of cancer immunotherapies depends upon the formation of intratumoral immune triads between antigen-presenting cells and antigen-specific CD4+ and CD8+ T cells. This interaction reprograms tumor-specific CD8+ T cells to exert potent effector functions and eradicate established solid tumors. [ABSTRACT FROM AUTHOR]

The immune system has a powerful ability to recognize and kill cancer cells, but its function is often suppressed within tumors, preventing clearance of disease. Functionally diverse innate and adaptive cellular lineages either drive or constrain immune reactions within tumors. The transcription factor (TF) BACH2 regulates the differentiation of multiple innate and adaptive cellular lineages, but its role in controlling tumor immunity has not been elucidated. Here, we demonstrate that BACH2 is required to establish immunosuppression within tumors. Tumor growth was markedly impaired in Bach2-deficient mice and coincided with intratumoral activation of both innate and adaptive immunity. However, augmented tumor clearance in the absence of Bach2 was dependent upon the adaptive immune system. Analysis of tumor-infiltrating lymphocytes from Bach2-deficient mice revealed high frequencies of rapidly proliferating effector CD4+ and CD8+ T cells that expressed the inflammatory cytokine IFN-γ. Effector T cell activation coincided with a reduction in the frequency of intratumoral Foxp3+ Tregs. Mechanistically, BACH2 promoted tumor immunosuppression through Treg-mediated inhibition of intratumoral CD8+ T cells and IFN-γ. These findings demonstrate that BACH2 is a key component of the molecular program of tumor immunosuppression and identify therapeutic targets for the reversal of immunosuppression in cancer. [ABSTRACT FROM AUTHOR]

Regulatory T (T reg ) cells suppress effector T (T eff ) cells and prevent immune-mediated rejection of cancer. Much less appreciated are mechanisms by which T eff cells antagonize T reg cells. Herein, we consider how complex reciprocal interactions between T eff and T reg cells shape their population dynamics within tumors. Under states of tolerance, including during tumor escape, suppressed T eff cells support T reg cell populations through antigen-dependent provision of interleukin (IL)-2. During immune activation, T eff cells can lose this supportive capacity and directly antagonize T reg cell populations to neutralize their immunosuppressive function. While this latter state is rarely achieved spontaneously within tumors, we propose that therapeutic induction of immune activation has the potential to stably disrupt immunosuppressive population states resulting in durable cancer regression. [ABSTRACT FROM AUTHOR]

The generation of CD8 + T-cell memory is a major aim of vaccination. While distinct subsets of CD8 + T-cells are generated following immunization that differ in their ability to confer long-term immunity against infection, the transcriptional profiles of these subsets within endogenous vaccine-induced CD8 + T cell responses have not been resolved. Here, we measure global transcriptional profiles of endogenous effector ( T EFF ), effector memory ( T EM ) and central memory ( T CM ) CD8 + T-cells arising from immunization with three distinct prime-boost vaccine regimens. While a proportion of transcripts were uniquely regulated within distinct CD8 + T cell populations, we observed progressive up- or down-regulation in the expression of a majority of differentially expressed transcripts when subsets were compared in the order T N > T CM > T EM > T EFF. Strikingly, when we compared global differences in gene expression between T N , T CM , T EM and T EFF cells with known transcriptional changes that result when CD8 + T cells repetitively encounter antigen, our analysis overwhelmingly favored a model whereby cumulative antigen stimulation drives differentiation specifically from T N > T CM > T EM > T EFF and this was common to all vaccines tested. These findings provide insight into the molecular basis of immunological memory and identify potential biomarkers for characterization of vaccine-induced responses and prediction of vaccine efficacy. [ABSTRACT FROM AUTHOR]

Through their functional diversification, distinct lineages of CD4+ T cells can act to either drive or constrain immune-mediated pathology. Transcription factors are critical in the generation of cellular diversity, and negative regulators antagonistic to alternate fates often act in conjunction with positive regulators to stabilize lineage commitment. Genetic polymorphisms within a single locus encoding the transcription factor BACH2 are associated with numerous autoimmune and allergic diseases including asthma, Crohn's disease, coeliac disease, vitiligo, multiple sclerosis and type 1 diabetes. Although these associations point to a shared mechanism underlying susceptibility to diverse immune-mediated diseases, a function for BACH2 in the maintenance of immune homeostasis has not been established. Here, by studying mice in which the Bach2 gene is disrupted, we define BACH2 as a broad regulator of immune activation that stabilizes immunoregulatory capacity while repressing the differentiation programs of multiple effector lineages in CD4+ T cells. BACH2 was required for efficient formation of regulatory (Treg) cells and consequently for suppression of lethal inflammation in a manner that was Treg-cell-dependent. Assessment of the genome-wide function of BACH2, however, revealed that it represses genes associated with effector cell differentiation. Consequently, its absence during Treg polarization resulted in inappropriate diversion to effector lineages. In addition, BACH2 constrained full effector differentiation within TH1, TH2 and TH17 cell lineages. These findings identify BACH2 as a key regulator of CD4+ T-cell differentiation that prevents inflammatory disease by controlling the balance between tolerance and immunity. [ABSTRACT FROM AUTHOR]

CD8 T cells play a key role in mediating protective immunity against selected pathogens after vaccination. Understanding the mechanism of this protection is dependent upon definition of the heterogeneity and complexity of cellular immune responses generated by different vaccines. Here, we identify previously unrecognized subsets of CD8 T cells based upon analysis of gene-expression patterns within single cells and show that they are differentially induced by different vaccines. Three prime-boost vector combinations encoding HIV Env stimulated antigen-specific CD8 T-cell populations of similar magnitude, phenotype, and functionality. Remarkably, however, analysis of single-cell gene-expression profiles enabled discrimination of a majority of central memory (CM) and effector memory (EM) CD8 T cells elicited by the three vaccines. Subsets of T cells could be defined based on their expression of Eomes, Cxcr3, and Ccrl, or Kirki, Kirgi, and CcrS in CM and EM cells, respectively, Of CM cells elicited by DNA prime-recombinant adenoviral (rAd) boost vectors, 67% were Eomes Ccrr Cxcr3, in contrast to only 7% and 2% stimulated by rAcl5-rAd5 or rAd-LCMV, respectively, Of EM cells elicited by DNArAd, 74% were KIrkl K!rgrCcr5T compared with only 26% and 20% for rAd5-rAd5 or rAd5-LCMV. Definition by single-cell gene profiling of specific CM and EM CD8 T-cell subsets that are differentially induced by different gene-based vaccines will facilitate the design and evaluation of vaccines, as well as enable our understanding of mechanisms of protective immunity. [ABSTRACT FROM AUTHOR]

Background: Breast radiotherapy as practised in the 1970s and 1980s resulted in significant myocardial exposure, and this was higher when the left breast was treated. It has been proposed that this difference might result in greater cardiovascular mortality following irradiation of the left breast when compared with the right. Methods: All cases of female breast cancer diagnosed between 1971 and 1988 and recorded on the Thames Cancer Registry database were followed up to the end of 2003 to identify cases who had died from ischaemic heart disease (IHD) or any cardiovascular disease (CVD). A proportional hazards regression analysis was performed, stratified by time since diagnosis, using as the baseline group those women with right-sided disease who did not receive radiotherapy, and adjusting for age at diagnosis. Results: A total of 20,871 women with breast cancer were included in the analysis, of which 51% had left-sided disease. Mortality at 15+ years after diagnosis was increased in recipients of left-breast radiotherapy compared to non-irradiated women with right-sided breast cancer, both for IHD (hazard ratio 1.59; 95% confidence interval 1.21-2.08; p = 0.001) and all CVD(hazard ratio 1.27; 95% confidence interval 1.07-1.51; p = 0.006). When irradiated women with left-sided breast cancer were compared with irradiated women with right-sided breast cancer, cardiovascular mortality at 15+ years after diagnosis was raised by around 25% (IHD: hazard ratio 1.23; 95% confidence interval 0.95-1.60; p = 0.114; CVD: hazard ratio 1.25; 95% confidence interval 1.05-1.49; p = 0.014). Conclusion: We have found an elevation in cardiovascular mortality more than 15 years after breast radiotherapy in women diagnosed with breast cancer between 1971 and 1988. The risk was greater following irradiation of the left breast compared with the right. This confirms that radiotherapy as practised in the 1970s and 1980s has resulted in significant long-term cardiac toxicity. In absolute terms, the increase in cardiovascular mortality induced by radiotherapy may be substantial, as these mortality events are relatively common. [ABSTRACT FROM AUTHOR]

It is thought that cancer cells engage in Warburg metabolism to meet intrinsic biosynthetic requirements of cell growth and proliferation. Papers by Chang et al. and Ho et al. show that Warburg metabolism enables tumor cells to restrict glucose availability to T cells, suppressing anti-tumor immunity. [ABSTRACT FROM AUTHOR]

Adoptive transfer of suppressive CD4+CD25+ thymic regulatory T cells (tTregs) can control auto- and alloimmune responses but typically requires in vitro expansion to reach the target cell number for efficacy. Although the adoptive transfer of expanded tTregs purified from umbilical cord blood ameliorates graft-versus-host disease in patients receiving hematopoietic stem cell transplantation for lymphohematopoietic malignancy, individual Treg products of 100 × 106 cells/kg are manufactured over an extended 19-day time period using a process that yields variable products and is both laborious and costly. These limitations could be overcome with the availability of 'off the shelf' Treg. Previously, the authors reported a repetitive restimulation expansion protocol that maintains Treg phenotype (CD4+25++127-Foxp3+), potentially providing hundreds to thousands of patient infusions. However, repetitive stimulation of effector T cells induces a well-defined program of exhaustion that leads to reduced T-cell survival and function. Unexpectedly, the authors found that multiply stimulated human tTregs do not develop an exhaustion signature and instead maintain their Treg gene expression pattern. The authors also found that tTregs expanded with one or two rounds of stimulation and tTregs expanded with three or five rounds of stimulation preferentially express distinct subsets of a group of five transcription factors that lock in Treg Foxp3 expression, Treg stability and suppressor function. Multiply restimulated Tregs also had increased transcripts characteristic of T follicular regulatory cells, a Treg subset. These data demonstrate that repetitively expanded human tTregs have a Treg-locking transcription factor with stable FoxP3 and without the classical T-cell exhaustion gene expression profile—desirable properties that support the possibility of off-the-shelf Treg therapeutics. [ABSTRACT FROM AUTHOR]

Summary Cancer cells must evade immune responses at distant sites to establish metastases. The lung is a frequent site for metastasis. We hypothesized that lung-specific immunoregulatory mechanisms create an immunologically permissive environment for tumor colonization. We found that T-cell-intrinsic expression of the oxygen-sensing prolyl-hydroxylase (PHD) proteins is required to maintain local tolerance against innocuous antigens in the lung but powerfully licenses colonization by circulating tumor cells. PHD proteins limit pulmonary type helper (Th)-1 responses, promote CD4 + -regulatory T (T reg ) cell induction, and restrain CD8 + T cell effector function. Tumor colonization is accompanied by PHD-protein-dependent induction of pulmonary T reg cells and suppression of IFN-γ-dependent tumor clearance. T-cell-intrinsic deletion or pharmacological inhibition of PHD proteins limits tumor colonization of the lung and improves the efficacy of adoptive cell transfer immunotherapy. Collectively, PHD proteins function in T cells to coordinate distinct immunoregulatory programs within the lung that are permissive to cancer metastasis. PaperClip [ABSTRACT FROM AUTHOR]

Summary: There have been substantial strides forward in our understanding of the contribution of regulatory T (Treg) cells to cancer immunosuppression. In this issue, we present a series of papers highlighting emerging themes on this topic relevant not only to our understanding of the fundamental biology of tumour immunosuppression but also to the design of new immunotherapeutic approaches. The substantially shared biology of CD4+ conventional T (Tconv) and Treg cells necessitates a detailed understanding of the potentially opposing functional consequences that immunotherapies will have on Treg and Tconv cells, a prominent example being the potential for Treg‐mediated hyperprogressive disease following anti‐PD‐1 therapy. Such understanding will aid patient stratification and the rational design of combination therapies. It is also becoming clear, however, that Treg cells within tumours exhibit distinct biological features to both Tconv cells and Treg cells in other tissues. These distinct features provide the opportunity for development of targeted immunotherapies with greater efficacy and reduced potential for inducing systemic toxicity. [ABSTRACT FROM AUTHOR]

Adoptive cell therapy (ACT) using autologous tumor-infiltrating lymphocytes (TIL) results in complete regression of advanced cancer in some patients, but the efficacy of this potentially curative therapy may be limited by poor persistence of TIL after adoptive transfer. Pharmacologic inhibition of the serine/threonine kinase Akt has recently been shown to promote immunologic memory in virus-specific murine models, but whether this approach enhances features of memory (e.g., long-term persistence) in TIL that are characteristically exhausted and senescent is not established. Here, we show that pharmacologic inhibition of Akt enables expansion of TIL with the transcriptional, metabolic, and functional properties characteristic of memory T cells. Consequently, Akt inhibition results in enhanced persistence of TIL after adoptive transfer into an immunodeficient animal model and augments antitumor immunity of CD8 T cells in a mouse model of cell-based immunotherapy. Pharmacologic inhibition of Akt represents a novel immunometabolomic approach to enhance the persistence of antitumor T cells and improve the efficacy of cell-based immunotherapy for metastatic cancer. [ABSTRACT FROM AUTHOR]

Adoptive cell transfer therapy using CD8+ T lymphocytes showed promising results eradicating metastatic malignancies. However, several regulatory mechanisms limit its efficacy. We studied the role of the expression of the transcription factor FOXP3 on CD8+ T cell function and anti-tumor immunity. Here we show that suboptimal T cell receptor stimulation of CD8+ T cells upregulates FOXP3 in vitro. Similarly, CD8 T cells transferred into tumor-bearing mice upregulate FOXP3 in vivo. Cell-intrinsic loss of FOXP3 by CD8+ T cells resulted in improved functionality after TCR stimulation and better antitumor responses in vivo. Inhibition of the FOXP3/NFAT interaction likewise improved CD8+ T cell functionality. Transcriptomic analysis of cells after TCR stimulation revealed an enrichment of genes implicated in the response to IFN-γ, IFN-α, inflammatory response, IL-6/JAK/STAT, G2M checkpoint and IL-2/STAT signaling in FOXP3-deficient CD8+ T cells with respect to FOXP3-wt CD8+ T cells. Our results suggest that transient expression of FOXP3 by CD8+ T cells in the tumor microenvironment restrains their anti-tumor activity, with clear implications for improving T cell responses during immunotherapy. [ABSTRACT FROM AUTHOR]

CD4+ regulatory T (Treg) cells, dependent upon the transcription factor Foxp3, contribute to tumour immunosuppression but are also required for immune homeostasis. There is interest in developing therapies that selectively target the immunosuppressive function of Treg cells within tumours without disrupting their systemic anti‐inflammatory function. High levels of expression of chemokine (C‐C motif) receptor 8 (CCR8) discriminate Treg cells within tumours from those found in systemic lymphoid tissues. It has recently been proposed that disruption of CCR8 function using blocking anti‐CCR8 antibodies results in reduced accumulation of Treg cells within tumours and disruption of their immunosuppressive function. Here, using Ccr8−/− mice, we show that CCR8 function is not required for Treg cell accumulation or immunosuppression in the context of syngeneic MC38 colorectal adenocarcinoma and B16 melanoma tumours. We observed high levels of CCR8 expression on tumour‐infiltrating Treg cells which were abolished in Ccr8−/− mice. High levels of CCR8 marked cells with high levels of suppressive function. However, whereas systemic ablation of Treg cells resulted in strikingly diminished tumour burden, growth of subcutaneously implanted tumours was unaffected by systemic CCR8 loss. Consistently, we observed minimal impact of systemic CCR8 ablation on the frequency, phenotype and function of tumour‐infiltrating Treg cells and conventional T (Tconv) function. These findings suggest that CCR8 is not required for Treg cell accumulation and immunosuppressive function within tumours and that depletion of CCR8+ Treg cells rather than blockade of CCR8 function is a more promising avenue for selective immunotherapy. [ABSTRACT FROM AUTHOR]

The molecular mechanisms responsible for the high immunosuppressive capacity of CD4+ Tregs in tumors are not well known. High-dimensional single-cell profiling of T cells from chemotherapy-naive individuals with non-small-cell lung cancer identified the transcription factor IRF4 as specifically expressed by a subset of intratumoral CD4+ effector Tregs with superior suppressive activity. In contrast to the IRF4- counterparts, IRF4+ Tregs expressed a vast array of suppressive molecules, and their presence correlated with multiple exhausted subpopulations of T cells. Integration of transcriptomic and epigenomic data revealed that IRF4, either alone or in combination with its partner BATF, directly controlled a molecular program responsible for immunosuppression in tumors. Accordingly, deletion of Irf4 exclusively in Tregs resulted in delayed tumor growth in mice while the abundance of IRF4+ Tregs correlated with poor prognosis in patients with multiple human cancers. Thus, a common mechanism underlies immunosuppression in the tumor microenvironment irrespective of the tumor type. [ABSTRACT FROM AUTHOR]

BTB and CNC homology 2 (Bach2) is a transcriptional repressor that is required for the formation of the germinal center (GC) and reactions, including class switch recombination and somatic hypermutation of Ig genes in B cells, within the GC. Although BCR-induced proliferation is essential for GC reactions, the function of Bach2 in regulating B cell proliferation has not been elucidated. In this study, we demonstrate that Bach2 is required to sustain high levels of B cell proliferation in response to BCR signaling. Following BCR engagement in vitro, B cells from Bach2-deficient (Bach2-/-) mice showed lower incorporation of BrdU and reduced cell cycle progression compared with wild-type cells. Bach2-/- B cells also underwent increased apoptosis, as evidenced by an elevated frequency of sub-G1 cells and early apoptotic cells. Transcriptome analysis of BCR-engaged B cells from Bach2-/- mice revealed reduced expression of the antiapoptotic gene Bcl2l1 encoding Bcl-xL and elevated expression of cyclin-dependent kinase inhibitor (CKI) family genes, including Cdkn1a, Cdkn2a, and Cdkn2b. Reconstitution of Bcl-xL expression partially rescued the proliferation defect of Bach2-/- B cells. Chromatin immunoprecipitation experiments showed that Bach2 bound to the CKI family genes, indicating that these genes are direct repression targets of Bach2. These findings identify Bach2 as a requisite factor for sustaining high levels of BCR-induced proliferation, survival, and cell cycle progression, and it promotes expression of Bcl-xL and repression of CKI genes. BCR-induced proliferation defects may contribute to the impaired GC formation observed in Bach2-/- mice. [ABSTRACT FROM AUTHOR]

Adoptive cell transfer (ACT) of purified naive, stem cell memory, and central memory T cell subsets results in superior persistence and antitumor immunity compared with ACT of populations containing more-differentiated effector memory and effector T cells. Despite a clear advantage of the less-differentiated populations, the majority of ACT trials utilize unfractionated T cell subsets. Here, we have challenged the notion that the mere presence of less-differentiated T cells in starting populations used to generate therapeutic T cells is sufficient to convey their desirable attributes. Using both mouse and human cells, we identified a T cell-T cell interaction whereby antigen-experienced subsets directly promote the phenotypic, functional, and metabolic differentiation of naive T cells. This process led to the loss of less-differentiated T cell subsets and resulted in impaired cellular persistence and tumor regression in mouse models following ACT. The T memory-induced conversion of naive T cells was mediated by a nonapoptotic Fas signal, resulting in Akt-driven cellular differentiation. Thus, induction of Fas signaling enhanced T cell differentiation and impaired antitumor immunity, while Fas signaling blockade preserved the antitumor efficacy of naive cells within mixed populations. These findings reveal that T cell subsets can synchronize their differentiation state in a process similar to quorum sensing in unicellular organisms and suggest that disruption of this quorum-like behavior among T cells has potential to enhance T cell-based immunotherapies. [ABSTRACT FROM AUTHOR]

The article presents a study identifying a novel role for the dual specificity tyrosinephosphorylation-regulated kinase DYRK1A in regulating the balance with the use of an unbiased chemical biology approach.

Enhancers regulate spatiotemporal gene expression and impart cell-specific transcriptional outputs that drive cell identity. Super-enhancers (SEs), also known as stretch-enhancers, are a subset of enhancers especially important for genes associated with cell identity and genetic risk of disease. CD4+ T cells are critical for host defence and autoimmunity. Here we analysed maps of mouse T-cell SEs as a non-biased means of identifying key regulatory nodes involved in cell specification. We found that cytokines and cytokine receptors were the dominant class of genes exhibiting SE architecture in T cells. Nonetheless, the locus encoding Bach2, a key negative regulator of effector differentiation, emerged as the most prominent T-cell SE, revealing a network in which SE-associated genes critical for T-cell biology are repressed by BACH2. Disease-associated single-nucleotide polymorphisms for immune-mediated disorders, including rheumatoid arthritis, were highly enriched for T-cell SEs versus typical enhancers or SEs in other cell lineages. Intriguingly, treatment of T cells with the Janus kinase (JAK) inhibitor tofacitinib disproportionately altered the expression of rheumatoid arthritis risk genes with SE structures. Together, these results indicate that genes with SE architecture in T cells encompass a variety of cytokines and cytokine receptors but are controlled by a 'guardian' transcription factor, itself endowed with an SE. Thus, enumeration of SEs allows the unbiased determination of key regulatory nodes in T cells, which are preferentially modulated by pharmacological intervention. [ABSTRACT FROM AUTHOR]

The pmel-1 T cell receptor transgenic mouse has been extensively employed as an ideal model system to study the mechanisms of tumor immunology, CD8+ T cell differentiation, autoimmunity and adoptive immunotherapy. The ‘zygosity’ of the transgene affects the transgene expression levels and may compromise optimal breeding scheme design. However, the integration sites for the pmel-1 mouse have remained uncharacterized. This is also true for many other commonly used transgenic mice created before the modern era of rapid and inexpensive next-generation sequencing. Here, we show that whole genome sequencing can be used to determine the exact pmel-1 genomic integration site, even with relatively ‘shallow’ (8X) coverage. The results were used to develop a validated polymerase chain reaction-based genotyping assay. For the first time, we provide a quick and convenient polymerase chain reaction method to determine the dosage of pmel-1 transgene for this freely and publically available mouse resource. We also demonstrate that next-generation sequencing provides a feasible approach for mapping foreign DNA integration sites, even when information of the original vector sequences is only partially known. [ABSTRACT FROM AUTHOR]

Naive CD8+ T cells rely upon oxidation of fatty acids as a primary source of energy. After antigen encounter, T cells shift to a glycolytic metabolism to sustain effector function. It is unclear, however, whether changes in glucose metabolism ultimately influence the ability of activated T cells to become long-lived memory cells. We used a fluorescent glucose analog, 2-NBDG, to quantify glucose uptake in activated CD8+ T cells. We found that cells exhibiting limited glucose incorporation had a molecular profile characteristic of memory precursor cells and an increased capacity to enter the memory pool compared with cells taking up high amounts of glucose. Accordingly, enforcing glycolytic metabolism by overexpressing the glycolytic enzyme phosphoglycerate mutase-1 severely impaired the ability of CD8+ T cells to form long-term memory. Conversely, activation of CD8+ T cells in the presence of an inhibitor of glycolysis, 2-deoxyglucose, enhanced the generation of memory cells and antitumor functionality. Our data indicate that augmenting glycolytic flux drives CD8+ T cells toward a terminally differentiated state, while its inhibition preserves the formation of long-lived memory CD8+ T cells. These results have important implications for improving the efficacy of T cell-based therapies against chronic infectious diseases and cancer. [ABSTRACT FROM AUTHOR]

Summary: Th17 cells have been described as short lived, but this view is at odds with their capacity to trigger protracted damage to normal and transformed tissues. We report that Th17 cells, despite displaying low expression of CD27 and other phenotypic markers of terminal differentiation, efficiently eradicated tumors and caused autoimmunity, were long lived, and maintained a core molecular signature resembling early memory CD8+ cells with stem cell-like properties. In addition, we found that Th17 cells had high expression of Tcf7, a direct target of the Wnt and β-catenin signaling axis, and accumulated β-catenin, a feature observed in stem cells. In vivo, Th17 cells gave rise to Th1-like effector cell progeny and also self-renewed and persisted as IL-17A-secreting cells. Multipotency was required for Th17 cell-mediated tumor eradication because effector cells deficient in IFN-γ or IL-17A had impaired activity. Thus, Th17 cells are not always short lived and are a less-differentiated subset capable of superior persistence and functionality. [ABSTRACT FROM AUTHOR]

Whereas effector CD4+ and CD8+ T cells promote immune activation and can drive clearance of infections and cancer, CD4+ regulatory T (Treg) cells suppress their function, contributing to both immune homeostasis and cancer immunosuppression. The transcription factor BACH2 functions as a pervasive regulator of T cell differentiation, promoting development of CD4+ Treg cells and suppressing the effector functions of multiple effector T cell (Teff) lineages. Here, we report the development of a stable cell-based bioluminescence assay of the transcription factor activity of BACH2. Tetracycline-inducible BACH2 expression resulted in suppression of phorbol 12-myristate 13-acetate (PMA)/ionomycin-driven activation of a luciferase reporter containing BACH2/AP-1 target sequences from the mouse Ifng + 18k enhancer. BACH2 expression repressed the luciferase signal in a dose-dependent manner but this activity was abolished at high levels of AP-1 signalling, suggesting contextual regulation of AP-1 driven gene expression by BACH2. Finally, using the reporter assay developed, we find that the histone deacetylase 3 (HDAC3)-selective inhibitor, RGFP966, inhibits BACH2-mediated repression of signal-driven luciferase expression. In addition to enabling mechanistic studies, this cell-based reporter may enable identification of small molecule agonists or antagonists of BACH2 function for drug development. [ABSTRACT FROM AUTHOR]

A summary is presented of an article published online at http://dx.doi.org/10.1126/science.aau0135 on the common mechanism that triggers dysfunction in tumors and T-cell stemness. It states that T-cells rely on consumption and uptake of extracellular nutrients to enable mTOR-driven anabolic growth and aerobic glycolysis. It comments on the possible impact that extracellular potassium in tumor interstitial fluid has on T-cell nutrient uptake and on T-cell antitumor capability and stemness.

The RV144 trial demonstrated that an experimental AIDS vaccine can prevent human immunodeficiency virus type 1 (HIV-1) infection in humans. Because of its limited efficacy, further understanding of the mechanisms of preventive AIDS vaccines remains a priority, and nonhuman primate (NHP) models of lentiviral infection provide an opportunity to define immunogens, vectors, and correlates of immunity. In this study, we show that prime-boost vaccination with a mismatched SIV envelope (Env) gene, derived from simian immunodeficiency virus SIVmac239, prevents infection by SIVsmE660 intrarectally. Analysis of different gene-based prime-boost immunization regimens revealed that recombinant adenovirus type 5 (rAd5) prime followed by replication-defective lymphocytic choriomeningitis virus (rLCMV) boost elicited robust CD4 and CD8 T-cell and humoral immune responses. This vaccine protected against infection after repetitive mucosal challenge with efficacies of 82% per exposure and 62% cumulatively. No effect was seen on viremia in infected vaccinated monkeys compared to controls. Protection correlated with the presence of neutralizing antibodies to the challenge viruses tested in peripheral blood mononuclear cells. These data indicate that a vaccine expressing a mismatched Env gene alone can prevent SIV infection in NHPs and identifies an immune correlate that may guide immunogen selection and immune monitoring for clinical efficacy trials. [ABSTRACT FROM AUTHOR]