搜索结果: 'gmp t cell activator'

Natural killer (NK) cells are an important innate defense against malignancies,and exogenous sources of NK cells have been developed as anti-cancer agents. Nevertheless,the apparent limitations of NK cells in clearing cancers have suggested that their efficacy might be augmented by combination with other treatments. We have developed cell-penetrating peptides that target the transcription factors ATF5,CEBPB,and CEBPD and that promote apoptotic cancer cell death both in vitro and in vivo without apparent toxicity to non-transformed cells. We report here that one such peptide,Dpep,significantly sensitizes a variety of tumor cell types to the cytotoxic activity of the NK cell line,NK-92MI. Such sensitization requires pre-exposure of tumor cells to Dpep and does not appear due to effects of Dpep on NK cells themselves. Our findings suggest that Dpep acts in this context to lower the apoptotic threshold of tumor cells to NK cell toxicity. Additionally,while Dpep pre-treatment does not prevent tumor cells from causing NK cell “inactivation”,it sensitizes cancer cells to repeated rounds of exposure to fresh NK cells. These findings thus indicate that Dpep pre-treatment is an effective strategy to sensitize cancer cells to the cytotoxic actions of NK cells. View Publication

Accumulating data have shown that targeting breast cancer stem cells (CSCs) is an auspicious way for anticancer therapies. This study demonstrated that the antirheumatic drug auranofin is a potent CSC inhibitor with anti-CSC action on breast cancer. This research focused on investigating the effect of auranofin on breast cancer and CSCs and its cellular mechanism. Mammosphere formation,colony formation,levels of CD44 high /CD24 low,and aldehyde dehydrogenase 1 expression in the cells were evaluated after auranofin treatment. The anti-CSC properties of auranofin were further examined by gel shift assay and cytokine detection. Auranofin suppressed cell growth,colony formation,migration,and mammosphere formation and triggered apoptosis in breast cancer. Auranofin decreased the CD44 high /CD24 low - and aldehyde dehydrogenase-expressed subpopulations,as well as the Stat3-DNA interaction and phosphorylated Stat3 level. Auranofin also decreased the extracellular levels of interleukin-8 (IL-8) in the mammosphere media. Auranofin suppressed the Stat3/IL-8 signal and killed CSCs; therefore,it may be a potential target for CSCs. View Publication

Histologic variant (HV) subtypes of bladder cancer are clinically aggressive tumors that are more resistant to standard therapy compared to conventional urothelial carcinoma (UC). Little is known about the transcriptional programs that account for their biological differences. Here we show using single cell analysis that HVs harbor a tumor cell state characterized by expression of MUC16 (CA125),MUC4,and KRT24 . This cell state is enriched in metastases,predicted to be highly resistant to chemotherapy,and linked with poor survival. We also find enriched expression of TM4SF1,a transmembrane protein,in HV tumor cells. Chimeric antigen receptor (CAR) T cells engineered against TM4SF1 protein demonstrated in vitro and in vivo activity against bladder cancer cell lines in a TM4SF1 expression-dependent manner,highlighting its potential as a therapeutic target. Subject terms: Bladder cancer,Tumour biomarkers,Targeted therapies View Publication

Understanding the molecular pathways driving the acute antiviral and inflammatory response to SARS-CoV-2 infection is critical for developing treatments for severe COVID-19. Here,we find decreasing number of circulating plasmacytoid dendritic cells (pDCs) in COVID-19 patients early after symptom onset,correlating with disease severity. pDC depletion is transient and coincides with decreased expression of antiviral type I IFN? and of systemic inflammatory cytokines CXCL10 and IL-6. Using an in vitro stem cell-based human pDC model,we further demonstrate that pDCs,while not supporting SARS-CoV-2 replication,directly sense the virus and in response produce multiple antiviral (interferons: IFN? and IFN?1) and inflammatory (IL-6,IL-8,CXCL10) cytokines that protect epithelial cells from de novo SARS-CoV-2 infection. Via targeted deletion of virus-recognition innate immune pathways,we identify TLR7-MyD88 signaling as crucial for production of antiviral interferons (IFNs),whereas Toll-like receptor (TLR)2 is responsible for the inflammatory IL-6 response. We further show that SARS-CoV-2 engages the receptor neuropilin-1 on pDCs to selectively mitigate the antiviral interferon response,but not the IL-6 response,suggesting neuropilin-1 as potential therapeutic target for stimulation of TLR7-mediated antiviral protection. View Publication

Stem cell competition could shed light on the tissue-based quality control mechanism that prevents carcinogenesis. To quantitatively evaluate stem cell competition in vitro,we developed a two-color intestinal organoid forming system. First,we improved a protocol of culturing organoids from intestinal leucine-rich-repeat containing G-protein-coupled receptor 5 (Lgr5)- enhanced green fluorescent protein (EGFP)high stem cells directly sorted on Matrigel without embedding. The organoid-forming potential (OFP) was 25{\%} of Lgr5-EGFPhigh cells sorted at one cell per well. Using this culture protocol with lineage tracing,we established a two-color organoid culture system by mixing stem cells expressing different fluorescent colors. To analyze stem cell competition,two-color organoids were formed by mixing X-ray-irradiated and non-irradiated intestinal stem cells. In the two-color organoids,irradiated stem cells exhibited a growth disadvantage,although the OFP of irradiated cells alone did not decrease significantly from that of non-irradiated cells. These results suggest that stem cell competition can be evaluated quantitively in vitro using our new system. View Publication

Energetic stress compels cells to evolve adaptive mechanisms to adjust their metabolism. Inhibition of mTOR kinase complex 1 (mTORC1) is essential for cell survival during glucose starvation. How mTORC1 controls cell viability during glucose starvation is not well understood. Here we show that the mTORC1 effectors eukaryotic initiation factor 4E binding proteins 1/2 (4EBP1/2) confer protection to mammalian cells and budding yeast under glucose starvation. Mechanistically,4EBP1/2 promote NADPH homeostasis by preventing NADPH-consuming fatty acid synthesis via translational repression of Acetyl-CoA Carboxylase 1 (ACC1),thereby mitigating oxidative stress. This has important relevance for cancer,as oncogene-transformed cells and glioma cells exploit the 4EBP1/2 regulation of ACC1 expression and redox balance to combat energetic stress,thereby supporting transformation and tumorigenicity in vitro and in vivo. Clinically,high EIF4EBP1 expression is associated with poor outcomes in several cancer types. Our data reveal that the mTORC1-4EBP1/2 axis provokes a metabolic switch essential for survival during glucose starvation which is exploited by transformed and tumor cells. How cells adapt to glucose starvation is still elusive. Here,Levy et al. show that the mTOR substrate 4EBP1 protects human,mouse,and yeast cells from glucose starvation and is exploited by cancer cells to promote tumorigenesis. View Publication

Understanding the molecular and cellular processes involved in lung epithelial regeneration may fuel the development of therapeutic approaches for lung diseases. We combine mouse models allowing diphtheria toxin-mediated damage of specific epithelial cell types and parallel GFP-labeling of functionally dividing cells with single-cell transcriptomics to characterize the regeneration of the distal lung. We uncover cell types,including Krt13+ basal and Krt15+ club cells,detect an intermediate cell state between basal and goblet cells,reveal goblet cells as actively dividing progenitor cells,and provide evidence that adventitial fibroblasts act as supporting cells in epithelial regeneration. We also show that diphtheria toxin-expressing cells can persist in the lung,express specific inflammatory factors,and transcriptionally resemble a previously undescribed population in the lungs of COVID-19 patients. Our study provides a comprehensive single-cell atlas of the distal lung that characterizes early transcriptional and cellular responses to concise epithelial injury,encompassing proliferation,differentiation,and cell-to-cell interactions. This study uses single-cell transcriptomics to examine how lung cells respond to targeted damage. The authors employ genetically modified mouse models and cell sorting to enrich for rare,actively dividing cells,revealing cell types/states and alternative differentiation paths. View Publication

The intestinal stem cell (ISC) marker LGR5 is a receptor for R-spondin (RSPO) that functions to potentiate Wnt signalling in the proliferating crypt. It has been recently shown that Wnt plays a priming role for ISC self-renewal by inducing RSPO receptor LGR5 expression. Despite its pivotal role in homeostasis,regeneration and cancer,little is known about the post-translational regulation of LGR5. Here,we show that the HECT-domain E3 ligases NEDD4 and NEDD4L are expressed in the crypt stem cell regions and regulate ISC priming by degrading LGR receptors. Loss of Nedd4 and Nedd4l enhances ISC proliferation,increases sensitivity to RSPO stimulation and accelerates tumour development in Apcmin mice with increased numbers of high-grade adenomas. Mechanistically,we find that both NEDD4 and NEDD4L negatively regulate Wnt/$\beta$-catenin signalling by targeting LGR5 receptor and DVL2 for proteasomal and lysosomal degradation. Our findings unveil the previously unreported post-translational control of LGR receptors via NEDD4/NEDD4L to regulate ISC priming. Inactivation of NEDD4 and NEDD4L increases Wnt activation and ISC numbers,which subsequently enhances tumour predisposition and progression. View Publication

This study quantifies uptake of a fluorescent glucose analog,(2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose) (2-NBDG),in a large panel of breast cancer cells and demonstrates potential to monitor changes in glycolysis caused by anticancer and endocrine therapies. Expressions of glucose transporter (GLUT 1) and hexokinase (HK I),which phosphorylates 2-NBDG,were measured via western blot in two normal mammary epithelial and eight breast cancer cell lines of varying biological subtype. Fluorescence intensity of each cell line labeled with 100 lM 2-NBDG for 20 min or unlabeled control was quantified. A subset of cancer cells was treated with anticancer and endocrine therapies,and 2-NBDG fluorescence changes were measured. Expression of GLUT 1 was necessary for uptake of 2-NBDG,as demonstrated by lack of 2-NBDG uptake in normal human mammary epithelial cells (HMECs). GLUT 1 expression and 2-NBDG uptake was ubiquitous among all breast cancer lines. Reduction and stimulation of 2-NBDG uptake was demonstrated by perturbation with anticancer agents,lonidamine (LND),and a-cyano-hydroxycinnamate (a-Cinn),respectively. LND directly inhibits HK and significantly reduced 2-NBDG fluorescence in a subset of two breast cancer cell lines. Conversely,when cells were treated with a-Cinn,a drug used to increase glycolysis,2-NBDG uptake was increased. Furthermore,tamoxifen (tam),a common endocrine therapy,was administered to estrogen receptor positive and negative (ER?/-) breast cells and demonstrated a decreased 2-NBDG uptake in ER? cells,reflecting a decrease in glycolysis. Results indicate that 2-NBDG uptake can be used to measure changes in glycolysis and has potential for use in early drug development. View Publication

Herpes simplex virus (HSV) tegument proteins are released into the cytoplasm during viral entry and hence are among the first viral proteins encountered by an infected cell. Despite the implied importance of these proteins in the evasion of host defenses,the function of some,like virion protein 11/12 (VP11/12),have not been clearly defined. Previously,we reported that VP11/12 is strongly tyrosine phosphorylated during the infection of lymphocytes but not in fibroblasts or an epithelial cell line (G. Zahariadis,M. J. Wagner,R. C. Doepker,J. M. Maciejko,C. M. Crider,K. R. Jerome,and J. R. Smiley,J. Virol. 82:6098-6108,2008). We also showed that tyrosine phosphorylation depends in part on the activity of the lymphocyte-specific Src family kinase (SFK) Lck in Jurkat T cells. These data suggested that VP11/12 is a substrate of Lck and that Lck is activated during HSV infection. Here,we show that HSV infection markedly increases the fraction of Lck phosphorylated on its activation loop tyrosine (Y394),a feature characteristic of activated Lck. A previous report implicated the immediate-early protein ICP0 and the viral serine/threonine kinases US3 and UL13 in the induction of a similar activated phenotype of SFKs other than Lck in fibroblasts and suggested that ICP0 interacts directly with SFKs through their SH3 domain. However,we were unable to detect an interaction between ICP0 and Lck in T lymphocytes,and we show that ICP0,US3,and UL13 are not strictly required for Lck activation. In contrast,VP11/12 interacted with Lck or Lck signaling complexes and was strictly required for Lck activation during HSV infection. Thus,VP11/12 likely modulates host cell signaling pathways for the benefit of the virus. View Publication

Human pluripotent stem cells (PSCs) exist in naive and primed states and provide important models to investigate the earliest stages of human development. Naive cells can be obtained through primed-to-naive resetting,but there are no reliable methods to prospectively isolate unmodified naive cells during this process. Here we report comprehensive profiling of cell surface proteins by flow cytometry in naive and primed human PSCs. Several naive-specific,but not primed-specific,proteins were also expressed by pluripotent cells in the human preimplantation embryo. The upregulation of naive-specific cell surface proteins during primed-to-naive resetting enabled the isolation and characterization of live naive cells and intermediate cell populations. This analysis revealed distinct transcriptional and X chromosome inactivation changes associated with the early and late stages of naive cell formation. Thus,identification of state-specific proteins provides a robust set of molecular markers to define the human PSC state and allows new insights into the molecular events leading to naive cell resetting. View Publication

Prostaglandins,particularly prostaglandin E2 (PGE2),play an important role during inflammation. This is exemplified by the clinical use of cyclooxygenase 2 inhibitors,which interfere with PGE2 synthesis,as effective antiinflammatory drugs. Here,we show that PGE2 directly promotes differentiation and proinflammatory functions of human and murine IL-17-producing T helper (Th17) cells. In human purified naive T cells,PGE2 acts via prostaglandin receptor EP2- and EP4-mediated signaling and cyclic AMP pathways to up-regulate IL-23 and IL-1 receptor expression. Furthermore,PGE2 synergizes with IL-1beta and IL-23 to drive retinoic acid receptor-related orphan receptor (ROR)-gammat,IL-17,IL-17F,CCL20,and CCR6 expression,which is consistent with the reported Th17 phenotype. While enhancing Th17 cytokine expression mainly through EP2,PGE2 differentially regulates interferon (IFN)-gamma production and inhibits production of the antiinflammatory cytokine IL-10 in Th17 cells predominantly through EP4. Furthermore,PGE2 is required for IL-17 production in the presence of antigen-presenting cells. Hence,the combination of inflammatory cytokines and noncytokine immunomodulators,such as PGE2,during differentiation and activation determines the ultimate phenotype of Th17 cells. These findings,together with the altered IL-12/IL-23 balance induced by PGE2 in dendritic cells,further highlight the crucial role of the inflammatory microenvironment in Th17 cell development and regulation. View Publication