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Immune checkpoint blockade (ICB) relieves CD8+ T-cell exhaustion in most mutated tumors, and TCF-1 is implicated in converting progenitor exhausted cells to functional effector cells. However, identifying mechanisms that can prevent functional senescence and potentiate CD8+ T-cell persistence for ICB non-responsive and resistant tumors remains elusive. We demonstrate that targeting Cbx3/HP1γ in CD8+ T cells augments transcription initiation and chromatin remodeling leading to increased transcriptional activity at Lef1 and Il21r. LEF-1 and IL-21R are necessary for Cbx3/HP1γ-deficient CD8+ effector T cells to persist and control ovarian cancer, melanoma, and neuroblastoma in preclinical models. The enhanced persistence of Cbx3/HP1γ-deficient CD8+ T cells facilitates remodeling of the tumor chemokine/receptor landscape ensuring their optimal invasion at the expense of CD4+ Tregs. Thus, CD8+ T cells heightened effector function consequent to Cbx3/HP1γ deficiency may be distinct from functional reactivation by ICB, implicating Cbx3/HP1γ as a viable cancer T-cell-based therapy target for ICB resistant, non-responsive solid tumors.

The global health burden due to sepsis and the associated cytokine storm is substantial. While early intervention has improved survival during the cytokine storm, those that survive can enter a state of chronic immunoparalysis defined by transient lymphopenia and functional deficits of surviving cells. Memory CD8 T cells provide rapid cytolysis and cytokine production following re-encounter with their cognate antigen to promote long-term immunity, and CD8 T cell impairment due to sepsis can pre-dispose individuals to re-infection. While the acute influence of sepsis on memory CD8 T cells has been characterized, if and to what extent pre-existing memory CD8 T cells recover remains unknown. Here, we observed that central memory CD8 T cells (TCM) from septic patients proliferate more than those from healthy individuals. Utilizing LCMV immune mice and a CLP model to induce sepsis, we demonstrated that TCM proliferation is associated with numerical recovery of pathogen-specific memory CD8 T cells following sepsis-induced lymphopenia. This increased proliferation leads to changes in composition of memory CD8 T cell compartment and altered tissue localization. Further, memory CD8 T cells from sepsis survivors have an altered transcriptional profile and chromatin accessibility indicating long-lasting T cell intrinsic changes. The sepsis-induced changes in the composition of the memory CD8 T cell pool and transcriptional landscape culminated in altered T cell function and reduced capacity to control L. monocytogenes infection. Thus, sepsis leads to long-term alterations in memory CD8 T cell phenotype, protective function and localization potentially changing host capacity to respond to re-infection.

Protective lung tissue-resident memory CD8+T cells (Trm) form after influenza A virus (IAV) infection. We show that IAV infection of mice generates CD69+CD103+and other memory CD8+T cell populations in lung-draining mediastinal lymph nodes (mLNs) from circulating naive or memory CD8+T cells. Repeated antigen exposure, mimicking seasonal IAV infections, generates quaternary memory (4M) CD8+T cells that protect mLN from viral infection better than 1M CD8+T cells. Better protection by 4M CD8+T cells associates with enhanced granzyme A/B expression and stable maintenance of mLN CD69+CD103+4M CD8+T cells, vs the steady decline of CD69+CD103+1M CD8+T cells, paralleling the durability of protective CD69+CD103+4M vs 1M in the lung after IAV infection. Coordinated upregulation in canonical Trm-associated genes occurs in circulating 4M vs 1M populations without the enrichment of canonical downregulated Trm genes. Thus, repeated antigen exposure arms circulating memory CD8+T cells with enhanced capacity to form long-lived populations of Trm that enhance control of viral infections of the mLN.

Abstract The goal of this study was to evaluate the feasibility of detecting Helicobacter pylori clarithromycin resistance in gastric mucosa using the amplification refractory mutation system combined with quantitative real‐time PCR (ARMS‐PCR). Gastric mucosal specimens (150) were collected from patients who were unsuccessfully treated for H. pylori eradication. Each specimen was divided into 2 samples. One sample was used to extract genomic DNA and detect any gene mutations of H. pylori produced by ARMS‐ PCR. Sequencing was used to assess the accuracy of this method. The other sample was used to culture H. pylori. The E‐test minimum inhibitory concentration (MIC) was used to assess clarithromycin resistance. The results were compared with a paired chi‐square test to validate the coincidence rate among the 3 methods. The coincidence rate between the sequencing and ARMS‐PCR results was 98.7%, thus verifying the accuracy of ARMS‐PCR. E‐tests detected 144 clarithromycin resistance cases, including 45 sensitivity cases; the resistance rate was 70%. The coincidence rate between the results of the E‐test and ARMS‐PCR was 97.1%, and no significant difference between the 2 methods was observed. ARMS‐PCR is a simple and fast method that has high sensitivity and specificity and can be used to detect the clarithromycin resistance of H. pylori in gastric mucosa. ARMS‐PCR is expected to be used to study drug resistance mechanisms and use in assays of individual therapies for H. pylori eradication.

Objective: To evaluate the efficacy and safety of MK-801 and its effect on lesion volume in rat models of acute brain injury. Data Sources: Key terms were “stroke”, “brain diseases”, “brain injuries”, “brain hemorrhage, traumatic”, “acute brain injury”, “dizocilpine maleate”, “dizocilpine”, “MK-801”, “MK801”, “rat”, “rats”, “rattus” and “murine”. PubMed, Cochrane library, EMBASE, the China National Knowledge Infrastructure, WanFang database, the VIP Journal Integration Platform (VJIP) and SinoMed databases were searched from their inception dates to March 2018. Data Selection: Studies were selected if they reported the effects of MK-801 in experimental acute brain injury. Two investigators independently conducted literature screening, data extraction, and methodological quality assessments. Outcome Measures: The primary outcomes included lesion volume and brain edema. The secondary outcomes included behavioral assessments with the Bederson neurological grading system and the water maze test 24 hours after brain injury. Results: A total of 52 studies with 2530 samples were included in the systematic review. Seventeen of these studies had a high methodological quality. Overall, the lesion volume (34 studies, n = 966, MD = −58.31, 95% CI: −66.55 to −50.07; P < 0.00001) and degree of cerebral edema (5 studies, n = 75, MD = −1.21, 95% CI: −1.50 to −0.91; P < 0.00001) were significantly decreased in the MK-801 group compared with the control group. MK-801 improved spatial cognition assessed with the water maze test (2 studies, n = 60, MD = −10.88, 95% CI: −20.75 to −1.00; P = 0.03) and neurological function 24 hours after brain injury (11 studies, n = 335, MD = −1.04, 95% CI: −1.47 to −0.60; P < 0.00001). Subgroup analysis suggested an association of reduction in lesion volume with various injury models (34 studies, n = 966, MD = −58.31, 95% CI: −66.55 to −50.07; P = 0.004). Further network analysis showed that 0–1 mg/kg MK-801 may be the optimal dose for treatment in the middle cerebral artery occlusion animal model. Conclusion: MK-801 effectively reduces brain lesion volume and the degree of cerebral edema in rat models of experimental acute brain injury, providing a good neuroprotective effect. Additionally, MK-801 has a good safety profile, and its mechanism of action is well known. Thus, MK-801 may be suitable for future clinical trials and applications.

Ezh2 is an histone methyltransferase that catalyzes H3K27me3. Here the authors show that Ezh2 promotes T follicular helper (TFH) differentiation and helper activity, by cooperating with Tcf1 to activate Bcl6 transcription and epigenetically repressing p19Arf, an antagonist of Bcl6 function and TFH cell survival.

Background/Aims: One of the most important impacts of personalized medicine is the connection between patients’ genotypes and their drug responses. Despite a series of studies exploring this relationship, the predictive ability of such analyses still needs to be strengthened. Methods: Here we present the Lq penalized network-constrained logistic regression (Lq-NLR) method to meet this need, in which the predictors are integrated into the gene expression data and biological network knowledge and are combined with a more aggressive penalty function. Response prediction models for two cancer targeting drugs (erlotinib and sorafenib) were developed from gene expression data and IC50 values from a large panel of cancer cell lines by utilizing the proposed approach. Then the drug responders were tested with the baseline tumor gene expression data, yielding an in vivo drug sensitivity prediction. Results: These results demonstrated the high effectiveness of this approach. One of the best results achieved by our method was a correlation of 0.841 between the cell line in vitro drug response and patient’s in vivo drug response. We then applied these two drug prediction models to develop a personalized medicine approach in which the subsequent treatment depends on each patient’s gene-expression profile. Conclusion: The proposed method is much better than the existing approach and can capture a more accurate reflection of the relationship between genotypes and phenotypes.

Induction of memory [CD8.sup.+] T cells is important for controlling infections such as malaria and HIV/AIDS and for cancer immunotherapy. Accurate assessment of antigen-specific (Ag-specific) [CD8.sup.+] T cells is critical for vaccine optimization and for defining correlates of protection. However, conditions for determining Ag-specific [CD8.sup.+] T cell responses ex vivo using intracellular cytokine staining (ICS) may be variable, especially in humans with complex antigens. Here, we used an attenuated whole parasite malaria vaccine model in humans and various experimental infections in mice to show that the duration of antigenic stimulation and timing of brefeldin A (BFA) addition influence the magnitude of Ag-specific and bystander T cell responses. Indeed, after immunization with an attenuated whole sporozoite malaria vaccine in humans, significantly higher numbers of IFN-[gamma]-producing memory [CD8.sup.+] T cells comprising Ag-specific and bystander responses were detected when the duration of Ag stimulation prior to addition of BFA was increased. Mechanistic analyses of virus-specific [CD8.sup.+] T cells in mice revealed that the increase in IFN-[gamma]-producing [CD8.sup.+] T cells was due to bystander activation of Ag-experienced memory [CD8.sup.+] T cells, and correlated with the proportion of Ag-experienced [CD8.sup.+] T cells in the stimulated populations. Incubation with anti-cytokine antibodies (e.g., IL-12) improved accuracy in detecting bona fide memory [CD8.sup.+] T cell responses, suggesting this as the mechanism for the bystander activation. These data have important implications for accurate assessment of immune responses generated by vaccines intended to elicit protective memory [CD8.sup.+] T cells., Introduction [CD8.sup.+] T cells have a role in mediating protection in humans against diverse pathogens impacting public health, such as HIV, influenza, and Plasmodium, the causative agent of malaria, and [...]

The β-catenin transcriptional coregulator is involved in various biological and pathological processes; however, its requirements in hematopoietic cells remain controversial. We re-targeted the Ctnnb1 gene locus to generate a true β-catenin-null mutant mouse strain. Ablation of β-catenin alone, or in combination with its homologue γ-catenin, did not affect thymocyte maturation, survival or proliferation. Deficiency in β/γ-catenin did not detectably affect differentiation of CD4+T follicular helper cells or that of effector and memory CD8+ cytotoxic cells in response to acute viral infection. In an MLL-AF9 AML mouse model, genetic deletion of β-catenin, or even all four Tcf/Lef family transcription factors that interact with β-catenin, did not affect AML onset in primary recipients, or the ability of leukemic stem cells (LSCs) in propagating AML in secondary recipients. Our data thus clarify on a long-standing controversy and indicate that β-catenin is dispensable for T cells and AML LSCs.

The expression of CD4, a critical co-receptor providing T cell help in adaptive immunity, is finely tuned during development. Here the authors show that two enhancer elements, E4p and the newly-defined E4m, coordinate the expression and heritable demethylation of Cd4 in thymocytes but are dispensable for its sustained expression in peripheral T cells.

Summary: Canonical NF-κB signaling is constitutively activated in acute myeloid leukemia (AML) stem cells and is required for maintenance of the self-renewal of leukemia stem cells (LSCs). However, any potential role for NF-κB non-canonical signaling in AML has been largely overlooked. Here, we report that stabilization of NF-κB-inducing kinase (NIK) suppresses AML. Mechanistically, stabilization of NIK activates NF-κB non-canonical signaling and represses NF-κB canonical signaling. In addition, stabilization of NIK-induced activation of NF-κB non-canonical signaling upregulates Dnmt3a and downregulates Mef2c, which suppresses and promotes AML development, respectively. Importantly, by querying the connectivity MAP using up- and downregulated genes that are present exclusively in NIK-stabilized LSCs, we discovered that verteporfin has anti-AML effects, suggesting that repurposing verteporfin to target myeloid leukemia is worth testing clinically. Our data provide a scientific rationale for developing small molecules to stabilize NIK specifically in myeloid leukemias as an attractive therapeutic option. : Xiu et al. identify a myeloid-leukemia-suppressive role of NIK, which is different from NIK’s tumor-promoting role in lymphoid neoplasms. They show that stabilization of NIK activates non-canonical but represses canonical NF-κB signaling, indicating that NF-κB non-canonical signaling has a role opposite to that of canonical signaling in AML. Keywords: NF-κB, NIK, RelB, RelA, DNMT3A, MEF2C, MLL-AF9, AML, leukemia stem cells, LSCs

CD62L+ central memory CD8+ T (TCM) cells provide enhanced protection than naive cells; however, the underlying mechanism, especially the contribution of higher-order genomic organization, remains unclear. Systematic Hi-C analyses reveal that antigen-experienced CD8+ T cells undergo extensive rewiring of chromatin interactions (ChrInt), with TCM cells harboring specific interaction hubs compared with naive CD8+ T cells, as observed at cytotoxic effector genes such as Ifng and Tbx21. TCM cells also acquire de novo CTCF (CCCTC-binding factor) binding sites, which are not only strongly associated with TCM-specific hubs but also linked to increased activities of local gene promoters and enhancers. Specific ablation of CTCF in TCM cells impairs rapid induction of genes in cytotoxic program, energy supplies, transcription, and translation by recall stimulation. Therefore, acquisition of CTCF binding and ChrInt hubs by TCM cells serves as a chromatin architectural basis for their transcriptomic dynamics in primary response and for imprinting the code of “recall readiness” against secondary challenge. [ABSTRACT FROM AUTHOR]