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1.
Nat Immunol ; 19(4): 342-353, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29507355

RESUMO

Pathogens have co-evolved with mosquitoes to optimize transmission to hosts. Mosquito salivary-gland extract is known to modulate host immune responses and facilitate pathogen transmission, but the underlying molecular mechanisms of this have remained unknown. In this study, we identified and characterized a prominent 15-kilodalton protein, LTRIN, obtained from the salivary glands of the mosquito Aedes aegypti. LTRIN expression was upregulated in blood-fed mosquitoes, and LTRIN facilitated the transmission of Zika virus (ZIKV) and exacerbated its pathogenicity by interfering with signaling through the lymphotoxin-ß receptor (LTßR). Mechanically, LTRIN bound to LTßR and 'preferentially' inhibited signaling via the transcription factor NF-κB and the production of inflammatory cytokines by interfering with the dimerization of LTßR during infection with ZIKV. Furthermore, treatment with antibody to LTRIN inhibited mosquito-mediated infection with ZIKV, and abolishing LTßR potentiated the infectivity of ZIKV both in vitro and in vivo. This study provides deeper insight into the transmission of mosquito-borne diseases in nature and supports the therapeutic potential of inhibiting the action of LTRIN to disrupt ZIKV transmission.


Assuntos
Aedes/virologia , Proteínas de Insetos/metabolismo , Saliva/metabolismo , Infecção por Zika virus/transmissão , Zika virus/patogenicidade , Animais , Humanos , Receptor beta de Linfotoxina/imunologia , Receptor beta de Linfotoxina/metabolismo , Camundongos , Mosquitos Vetores/química , Mosquitos Vetores/imunologia , Mosquitos Vetores/metabolismo , Saliva/química
2.
Proc Natl Acad Sci U S A ; 119(47): e2208274119, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36383602

RESUMO

Lyme spirochetes have coevolved with ticks to optimize transmission to hosts using tick salivary molecules (TSMs) to counteract host defenses. TSMs modulate various molecular events at the tick-host interface. Lymphotoxin-beta receptor (LTßR) is a vital immune receptor and plays protective roles in host immunity against microbial infections. We found that Ltbr knockout mice were more susceptible to Lyme disease spirochetes, suggesting the involvement of LTßR signaling in tick-borne Borrelia infection. Further investigation showed that a 15-kDa TSM protein from Ixodes persulcatus (I. persulcatus salivary protein; IpSAP) functioned as an immunosuppressant to facilitate the transmission and infection of Lyme disease spirochetes. IpSAP directly interacts with LTßR to block its activation, thus inhibiting the downstream signaling and consequently suppressing immunity. IpSAP immunization provided mice with significant protection against I. persulcatus-mediated Borrelia garinii infection. Notably, the immunization showed considerable cross-protection against other Borrelia infections mediated by other ixodid ticks. One of the IpSAP homologs from other ixodid ticks showed similar effects on Lyme spirochete transmission. Together, our findings suggest that LTßR signaling plays an important role in blocking the transmission and pathogenesis of tick-borne Lyme disease spirochetes, and that IpSAP and its homologs are promising candidates for broad-spectrum vaccine development.


Assuntos
Grupo Borrelia Burgdorferi , Borrelia burgdorferi , Ixodes , Doença de Lyme , Camundongos , Animais , Borrelia burgdorferi/genética , Saliva , Ixodes/fisiologia , Receptor beta de Linfotoxina
3.
Crit Rev Food Sci Nutr ; : 1-17, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39049742

RESUMO

Diabetes has become a serious public health crisis, presenting significant challenges to individuals worldwide. As the largest organ in the human body, skeletal muscle is a significant target of this chronic disease, yet muscle wasting as a complication of diabetes is still not fully understood and effective treatment methods have yet to be developed. Here, we discuss the targets involved in inducing muscle wasting under diabetic conditions, both validated targets and emerging targets. Diabetes-induced skeletal muscle wasting is known to involve changes in various signaling molecules and pathways, such as protein degradation pathways, protein synthesis pathways, mitochondrial function, and oxidative stress inflammation. Recent studies have shown that some of these present potential as promising therapeutic targets, including the neuregulin 1/epidermal growth factor receptor family, advanced glycation end-products, irisin, ferroptosis, growth differentiation factor 15 and more. This study's investigation and discussion of such pathways and their potential applications provides a theoretical basis for the development of clinical treatments for diabetes-induced muscle wasting and a foundation for continued focus on this disease.

4.
J Sci Food Agric ; 104(7): 4438-4452, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38323712

RESUMO

BACKGROUND: The gut microbiota is intricate and susceptible to multiple factors, with diet being a major contributor. The present study aimed to investigate the impact of four commonly used laboratory animal control diets, namely Keao Xieli's maintenance diet (KX), HFK's 1025 (HF), Research Diets' D12450B (RD), and Lab Diet's 5CC4 (LD), on the gut microbiota of mice. RESULTS: A total of 40 mice were randomly assigned to four groups, and each group was fed one of the four diets for a duration of 8 weeks. The assessment of gut microbiota was conducted using 16S rRNA sequencing both at the beginning of the study (week 0) and the end (week 8), which served as the baseline and endpoint samples, respectively. Following the 8-week feeding period, no significant differences were observed in physiological parameters, including body weight, visceral weight, and blood biochemical indices, across the four groups. Nonetheless, relative to the baseline, discernible alterations in the gut microbiota were observed in all groups, encompassing shifts in beta-diversity, hierarchical clustering, and key genera. Among the four diets, HF diet exhibited a significant influence on alpha-diversity, RD diet brought about notable changes in microbial composition at the phylum level, and LD diet demonstrated an interconnected co-occurrence network. Mantel analysis indicated no significant correlation between physiological parameters and gut microbiota in the four groups. CONCLUSION: Overall, our study demonstrated that the four control diets had a minimal impact on physiological parameters, while exerting a distinct influence on the gut microbiota after 8 weeks. © 2024 Society of Chemical Industry.


Assuntos
Microbioma Gastrointestinal , Camundongos , Animais , RNA Ribossômico 16S/genética , Dieta/veterinária , Animais de Laboratório/genética
5.
J Sci Food Agric ; 104(2): 675-685, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37653259

RESUMO

BACKGROUND: Ark clams, a seafood abundant in various nutrients, are widely consumed worldwide. This study aimed to investigate the protective benefits of two common ark clams in Korea, Scapharca subcrenata (SS) and Tegillarca granosa (TG), on gut health in d-galactose (d-gal)-induced aging rats. RESULTS: Thirty-two Wistar rats (11 weeks old) were randomly allocated into four groups: a CON group (normal diet + saline intraperitoneal (i.p.) injection), a CD group (normal diet + d-gal i.p. injection), an SS group (normal diet with 5% SS supplementation + d-gal i.p. injection), and a TG group (normal diet with 5% TG supplementation + d-gal i.p. injection). After 12 weeks of treatment, histopathological results showed that gut barrier damage was alleviated in rats of the SS and TG groups, as evidenced by increases in mucus layer thickness and goblet cell numbers. Meanwhile, the two groups supplemented with ark clams showed an evident reduction in oxidative stress biomarkers (malondialdehyde and protein carbonyl content levels in the colon) and an increase in the immune-related factor (immunoglobulin A level in the plasma) in rats. The 16S ribosomal RNA analysis revealed that SS and TG ark clams significantly increased the proliferations of Bacteroidetes at the phylum level and Parabacteroides at the genus level. Additionally, the levels of the three main short-chain fatty acids in the cecal contents were also significantly increased in the SS and TG groups. CONCLUSION: Our results indicated a potent preventive effect of SS and TG ark clams on d-gal-induced gut injury, suggesting that ark clams may be a promising dietary component for intervening in aging. © 2023 Society of Chemical Industry.


Assuntos
Bivalves , Microbioma Gastrointestinal , Ratos , Animais , Galactose/metabolismo , Ratos Wistar , Carbonilação Proteica , Envelhecimento , Estresse Oxidativo , Suplementos Nutricionais
6.
Angew Chem Int Ed Engl ; 62(27): e202304754, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37126395

RESUMO

Understanding the nature of single-atom catalytic sites and identifying their spectroscopic fingerprints are essential prerequisites for the rational design of target catalysts. Here, we apply correlated in situ X-ray absorption and infrared spectroscopy to probe the edge-site-specific chemistry of Co-N-C electrocatalyst during the oxygen reduction reaction (ORR) operation. The unique edge-hosted architecture affords single-atom Co site remarkable structural flexibility with adapted dynamic oxo adsorption and valence state shuttling between Co(2-δ)+ and Co2+ , in contrast to the rigid in-plane embedded Co1 -Nx counterpart. Theoretical calculations demonstrate that the synergistic interplay of in situ reconstructed Co1 -N2 -oxo with peripheral oxygen groups gives a rise to the near-optimal adsorption of *OOH intermediate and substantially increases the activation barrier for its dissociation, accounting for a robust acidic ORR activity and 2e- selectivity for H2 O2 production.

7.
Planta ; 252(5): 88, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33057902

RESUMO

MAIN CONCLUSION: Xanthomonas campestris pv. campestris 8004 secretes several effector proteins that interfere with plant phosphorylation. Xanthomonas campestris pv. campestris (Xcc) can infect cruciferous plants and cause black rot. The strain Xcc8004 secretes effector proteins that interfere with plant cellular processes into host cells using a type III secretion (T3S) system. Several of the 24 predicted T3S effectors in the Xcc8004 genome have been implicated in the suppression of the Arabidopsis thaliana pattern-triggered immunity (PTI) response. We used an A. thaliana mesophyll protoplast-based assay to identify Xcc8004 T3S effectors that effectively interfere with PTI signalling induced by the bacterial peptide flg22. 11 of the 24 tested effector proteins (XopK, XopQ, HrpW, XopN, XopAC, XopD, XopZ1, XopAG, AvrBs2, XopL and XopX-1) inhibited expression of the flg22-inducible gene FRK1, and five effectors (XopK, XopG, XopQ, XopL and XopX-1) inhibited the expression of the flg22-inducible gene WRKY33. Therefore, there are 12 effector proteins that can inhibit the expression of relevant flg22-inducible genes. It was further investigated whether the 12 effector proteins affect the phosphorylation activation of mitogen-activated protein (MAP) kinases MPK3/MPK6, and four effector proteins (XopK, XopQ, XopZ1 and XopX-1) were found to markedly inhibit MPK3/MPK6 activation. Moreover, a subcellular localisation analysis revealed that the tested effectors were localised within various subcellular compartments. These results indicate that multiple T3S effectors in the Xcc8004 genome interfere with flg22-induced PTI signalling via various molecular mechanisms.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Bactérias , Fatores de Transcrição , Xanthomonas campestris , Arabidopsis/efeitos dos fármacos , Proteínas de Bactérias/farmacologia , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Protoplastos/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/farmacologia , Xanthomonas campestris/química
8.
Hepatology ; 66(4): 1067-1082, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28445927

RESUMO

Strong tolerance to hepatitis B virus (HBV) surface antigens limits the therapeutic effect of the conventional hepatitis B surface antigen (HBsAg) vaccination in both preclinical animal models and patients with chronic hepatitis B (CHB) infection. In contrast, we observed that clinical CHB patients presented less immune tolerance to the preS1 domain of HBV large surface antigen. To study whether targeting the weak tolerance of the preS1 region could improve therapy gain, we explored vaccination with the long peptide of preS1 domain for HBV virions clearance. Our study showed that this preS1-polypeptide rather than HBsAg vaccination induced robust immune responses in HBV carrier mice. The anti-preS1 rapidly cleared HBV virions in vivo and blocked HBV infection to hepatocytes in vitro. Intriguingly, vaccination of preS1-polypeptide even reduced the tolerized status of HBsAg, opening a therapeutic window for the host to respond to the HBsAg vaccine. A sequential administration of antigenically distinct preS1-polypeptide and HBsAg vaccines in HBV carrier mice could finally induce HBsAg/hepatitis B surface antibody serological conversion and clear chronic HBV infection in carrier mice. CONCLUSION: These results suggest that preS1 can function as a therapeutic vaccine for the control of CHB. (Hepatology 2017;66:1067-1082).


Assuntos
Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Tolerância Imunológica , Precursores de Proteínas/imunologia , Adulto , Animais , Modelos Animais de Doenças , Feminino , Hepatite B/imunologia , Hepatite B/prevenção & controle , Humanos , Imunogenicidade da Vacina , Masculino , Camundongos , Pessoa de Meia-Idade
9.
Nutrients ; 16(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38542759

RESUMO

Previous studies have reported the therapeutic effects of oleuropein (OP) consumption on the early stage of diabetic nephropathy and diabetic cardiomyopathy. However, the efficacy of OP on the long-course of these diabetes complications has not been investigated. Therefore, in this study, to investigate the relieving effects of OP intake on these diseases, and to explore the underlying mechanisms, db/db mice (17-week-old) were orally administrated with OP (200 mg/kg bodyweight) for 15 weeks. We found that OP reduced expansion of the glomerular mesangial matrix, renal inflammation, renal fibrosis, and renal apoptosis. Meanwhile, OP treatment exerted cardiac anti-fibrotic, anti-inflammatory, and anti-apoptosis effects. Notably, transcriptomic and bioinformatic analyses indicated 290 and 267 differentially expressed genes in the kidney and heart replying to OP treatment, respectively. For long-course diabetic nephropathy, OP supplementation significantly upregulated the cyclic guanosine monophosphate-dependent protein kinase (cGMP-PKG) signaling pathway. For long-course diabetic cardiomyopathy, p53 and cellular senescence signaling pathways were significantly downregulated in response to OP supplementation. Furthermore, OP treatment could significantly upregulate the transcriptional expression of the ATPase Na+/K+ transporting subunit alpha 3, which was enriched in the cGMP-PKG signaling pathway. In contrast, OP treatment could significantly downregulate the transcriptional expressions of cyclin-dependent kinase 1, G two S phase expressed protein 1, and cyclin B2, which were enriched in p53 and cellular senescence signal pathways; these genes were confirmed by qPCR validation. Overall, our findings demonstrate that OP ameliorated long-course diabetic nephropathy and cardiomyopathy in db/db mice and highlight the potential benefits of OP as a functional dietary supplement in diabetes complications treatment.


Assuntos
Diabetes Mellitus Tipo 2 , Cardiomiopatias Diabéticas , Nefropatias Diabéticas , Glucosídeos Iridoides , Camundongos , Animais , Nefropatias Diabéticas/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Cardiomiopatias Diabéticas/complicações , Proteína Supressora de Tumor p53/metabolismo , Rim/metabolismo
10.
Biol Direct ; 19(1): 45, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38863009

RESUMO

BACKGROUND: Glioma is a common tumor that occurs in the brain and spinal cord. Hypoxia is a crucial feature of the tumor microenvironment. Tumor-associated macrophages/microglia play a crucial role in the advancement of glioma. This study aims to illuminate the detailed mechanisms by which hypoxia regulates microglia and, consequently, influences the progression of glioma. METHODS: The glioma cell viability and proliferation were analyzed by cell counting kit-8 assay and 5-ethynyl-2'-deoxyuridine assay. Wound healing assay and transwell assay were implemented to detect glioma cell migration and invasion, respectively. Enzyme-linked immunosorbent assay was conducted to detect protein levels in cell culture medium. The protein levels in glioma cells and tumor tissues were evaluated using western blot analysis. The histological morphology of tumor tissue was determined by hematoxylin-eosin staining. The protein expression in tumor tissues was determined using immunohistochemistry. Human glioma xenograft in nude mice was employed to test the influence of hypoxic microglia-derived interleukin-1beta (IL-1ß) and heparanase (HPSE) on glioma growth in vivo. RESULTS: Hypoxic HMC3 cells promoted proliferation, migration, and invasion abilities of U251 and U87 cells by secreting IL-1ß, which was upregulated by hypoxia-induced activation of hypoxia inducible factor-1alpha (HIF-1α). Besides, IL-1ß from HMC3 cells promoted glioma progression and caused activation of nuclear factor-κB (NF-κB) and upregulation of HPSE in vivo. We also confirmed that IL-1ß facilitated HPSE expression in U251 and U87 cells by activating NF-κB. Hypoxic HMC3 cells-secreted IL-1ß facilitated the proliferation, migration, and invasion of U251 and U87 cells via NF-κB-mediated upregulation of HPSE expression. Finally, we revealed that silencing HPSE curbed the proliferation and metastasis of glioma in mice. CONCLUSION: Hypoxia-induced activation of HIF-1α/IL-1ß axis in microglia promoted glioma progression via NF-κB-mediated upregulation of HPSE expression.


Assuntos
Glioma , Glucuronidase , Subunidade alfa do Fator 1 Induzível por Hipóxia , Interleucina-1beta , Camundongos Nus , Microglia , NF-kappa B , Regulação para Cima , Glioma/metabolismo , Glioma/genética , Glioma/patologia , Interleucina-1beta/metabolismo , Interleucina-1beta/genética , Microglia/metabolismo , Animais , NF-kappa B/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Camundongos , Glucuronidase/metabolismo , Glucuronidase/genética , Linhagem Celular Tumoral , Progressão da Doença , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Proliferação de Células , Movimento Celular , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Hipóxia/genética
11.
Nutrients ; 15(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36839338

RESUMO

Cedryl acetate (CA), also called acetyl cedrene, is approved by the FDA as a flavoring or adjuvant to be added to foods. In this study, we aimed to investigate the preventive benefits of CA on obesity and obesity-related metabolic syndrome caused by a high-fat diet (HFD). Three groups of C57BL/6J mice (ten-week-old) were fed Chow, an HFD, or an HFD with CA supplementation (100 mg/kg) for 19 weeks. We observed that CA supplementation significantly reduced weight gain induced by an HFD, decreased the weight of the visceral fat pads, and prevented adipocyte hypertrophy in mice. Moreover, mice in the CA group showed significant improvements in hepatic lipid accumulation, glucose intolerance, insulin resistance, and gluconeogenesis compared with the mice in the HFD group. Since 16S rRNA analysis revealed that the gut microbiota in the CA and HFD groups were of similar compositions at the phylum and family levels, CA may have limited effects on gut microbiota in HFD-fed mice. The beneficial effects on the metabolic parameters of CA were reflected by CA's regulation of metabolism-related gene expression in the liver (including Pepck, G6Pase, and Fbp1) and the epididymal white adipose tissues (including PPARγ, C/EBPα, FABP4, FAS, Cytc, PGC-1α, PRDM16, Cidea, and COX4) of the mice. In summary, a potent preventive effect of CA on HFD-induced obesity and related metabolic syndrome was highlighted by our results, and CA could be a promising dietary component for obesity intervention.


Assuntos
Acetatos , Adiposidade , Síndrome Metabólica , Animais , Camundongos , Acetatos/farmacologia , Dieta Hiperlipídica , Suplementos Nutricionais , Glucose/metabolismo , Homeostase , Síndrome Metabólica/complicações , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , RNA Ribossômico 16S/metabolismo
12.
Mol Nutr Food Res ; 67(14): e2200665, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37143286

RESUMO

SCOPE: Excellent health-promoting effects of cedrol (CED), including anti-inflammatory, anti-arthritic, and antinociceptive effects, have been reported. The present study aims to investigate the preventive effects of CED on high-fat diet (HFD)-induced obesity and the related metabolic syndrome, and to delineate the underlying mechanism. METHODS AND RESULTS: Ten-week-old C57BL/6J mice are fed chow, HFD, or HFD supplemented with CED (0.2% w/w) for 19 weeks. Results demonstrate that CED effectively reduces HFD-induced body weight gain, decreases visceral fat pad weight, and significantly prevents adipocyte hypertrophy in mice. HFD-induced hepatic steatosis, glucose intolerance, insulin resistance, and gluconeogenesis are ameliorated by CED supplementation. 16S rRNA analysis reveals that CED does not change gut microbiota composition at the phylum and genus levels, indicating that CED may have limited effects on gut microbiota in HFD-fed mice. Further transcriptome analysis of epididymal white adipose tissue reveals reprogrammed RNA profiles by CED. CONCLUSION: These results demonstrate that incorporating CED in the diet can prevent HFD-induced obesity and related metabolic syndrome, and highlight that CED can be a promising dietary component for obesity therapeutic intervention.


Assuntos
Dieta Hiperlipídica , Síndrome Metabólica , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Síndrome Metabólica/etiologia , Síndrome Metabólica/prevenção & controle , RNA Ribossômico 16S , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/prevenção & controle , Obesidade/tratamento farmacológico
13.
Cell Metab ; 34(12): 2018-2035.e8, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36351432

RESUMO

A hostile microenvironment in tumor tissues disrupts endoplasmic reticulum homeostasis and induces the unfolded protein response (UPR). A chronic UPR in both cancer cells and tumor-infiltrating leukocytes could facilitate the evasion of immune surveillance. However, how the UPR in cancer cells cripples the anti-tumor immune response is unclear. Here, we demonstrate that, in cancer cells, the UPR component X-box binding protein 1 (XBP1) favors the synthesis and secretion of cholesterol, which activates myeloid-derived suppressor cells (MDSCs) and causes immunosuppression. Cholesterol is delivered in the form of small extracellular vesicles and internalized by MDSCs through macropinocytosis. Genetic or pharmacological depletion of XBP1 or reducing the tumor cholesterol content remarkably decreases MDSC abundance and triggers robust anti-tumor responses. Thus, our data unravel the cell-non-autonomous role of XBP1/cholesterol signaling in the regulation of tumor growth and suggest its inhibition as a useful strategy for improving the efficacy of cancer immunotherapy.


Assuntos
Células Mieloides , Neoplasias , Proteína 1 de Ligação a X-Box/genética , Colesterol
14.
ACS Appl Mater Interfaces ; 14(26): 29822-29831, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35733359

RESUMO

The feature endowing atomic Ni-N-C electrocatalysts with exceptional intrinsic alkaline hydrogen evolution activity is hitherto not well-documented and remains elusive. To this end, we rationally exploited the hierarchical porous carbon microstructures as scaffolds to construct unique Ni-N2+2-S active sites to boost the sluggish Volmer reaction kinetics. Density functional theory reveals an obvious d-band center (ϵd) upshift of the edge-hosted Ni-N2+2-S sites compared with pristine Ni-N4, which translates to a more stabilized OH adsorption. Moreover, the synergetic dual-site (Ni and S atom) interplay gives rise to a decoupled regulation of the adsorption strength of intermediate species (OHad, Had) and thereby energetic water dissociation kinetics. Bearing these in mind, sodium thiosulfate was deliberately adopted as an additive in the molten salt system for controllable synthesis, considering the simultaneous catalyst morphology and active-site modulation. The target Ni-N2+2-S catalyst delivers a low working overpotential (83 mV@10 mA cm-2) and Tafel slope (100.5 mV dec-1) comparable to those of representative transition metal-based electrodes in alkaline media. The present study provides insights into the metal active-site geometry and promising synergistic effects over single-atom catalysis.

15.
Sci Immunol ; 7(67): eabi6899, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34995098

RESUMO

It is a challenge to effectively reactivate preexisting tumor-infiltrating lymphocytes (TILs) without causing severe toxicity. Interleukin-12 (IL-12) can potently activate lymphocytes, but its clinical use is limited by its short half-life and dose-related toxicity. In this study, we developed a tumor-conditional IL-12 (pro-IL-12), which masked IL-12 with selective extracellular receptor­binding domains of the IL-12 receptor while preferentially and persistently activating TILs after being unmasked by matrix metalloproteinases expressed by tumors. Systemic delivery of pro-IL-12 demonstrated reduced toxicity but better control of established tumors compared with IL-12-Fc. Mechanistically, antitumor responses induced by pro-IL-12 were dependent on TILs and IFNγ. Furthermore, direct binding of IL-12 to IL-12R on CD8+, not CD4+, T cells was essential for maximal effectiveness. Pro-IL-12 improved the efficacy of both immune checkpoint blockade and targeted therapy when used in combination. Therefore, our study demonstrated that pro-IL-12 could rejuvenate TILs, which then combined with current treatment modalities while limiting adverse effects for treating established tumors.


Assuntos
Interleucina-12/imunologia , Neoplasias/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos
16.
J Exp Med ; 219(12)2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36165896

RESUMO

Checkpoint blockade immunotherapy releases the inhibition of tumor-infiltrating lymphocytes (TILs) but weakly induces TIL proliferation. Exogenous IL-15 could further expand TILs and thus synergize with αPD-L1 therapy. However, systemic delivery of IL-15 extensively expands peripheral NK cells, causing severe toxicity. To redirect IL-15 to intratumoral PD-1+CD8+T effector cells instead of NK cells for better tumor control and lower toxicity, we engineered an anti-PD-1 fusion with IL-15-IL-15Rα, whose activity was geographically concealed by immunoglobulin Fc region with an engineered linker (αPD-1-IL-15-R) to bypass systemic NK cells. Systematic administration of αPD-1-IL-15-R elicited extraordinary antitumor efficacy with undetectable toxicity. Mechanistically, cis-delivery of αPD-1-IL-15-R vastly expands tumor-specific CD8+T cells for tumor rejection. Additionally, αPD-1-IL-15-R upregulated PD-1 and IL-15Rß on T cells to create a feedforward activation loop, thus rejuvenating TILs, not only resulting in tumor control in situ, but also suppressing tumor metastasis. Collectively, renavigating IL-15 to tumor-specific PD-1+CD8+T cells, αPD-1-IL-15-R elicits effective systemic antitumor immunity.


Assuntos
Interleucina-15 , Neoplasias , Linfócitos T CD8-Positivos , Humanos , Inibidores de Checkpoint Imunológico , Interleucina-15/farmacologia , Linfócitos do Interstício Tumoral
17.
ACS Appl Mater Interfaces ; 14(45): 50849-50857, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36321608

RESUMO

Early transition metals offer promising orthogonal reactivity to catalytic processes promoted by late transition metals. Nevertheless, exploiting variable single-atomic configurations as reactive centers is hitherto not well documented owing to their oxophilic nature. Herein we report an in-situ grafting strategy that employs nitrogenated holey carbon nitrides as a scaffold and invokes the reasonably good match of temperature-dependent pyrolysis to stabilize an atomic titanium-nitrogen (Ti1N2OH) moiety onto the hierarchical porous carbon support (Ti1/NC-SAC). The Ti1/NC-SAC as the cathode in dye-sensitized solar cells assembly exhibited superior electrocatalytic activity toward the triiodine reduction reaction, comparable to the conventional Pt cathode. DFT studies theoretically identified that the intrinsic robust triiodine reduction activity is essentially governed by the unique edge-hosted Ti sites, from both aspects, near-optimal adsorption of I intermediate and electron-donating ability. This work sheds light on the rational design of Ti-based SACs and their applications in photovoltaic fields.

18.
Appl Ergon ; 93: 103370, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33497954

RESUMO

The past decade has seen increasing popularity of large display-based freehand interaction. This study examined the effects of body posture, interaction distance and target size on freehand interaction with a large display. Participants performed pointing and dragging tasks by freehand interaction with a large display under sitting and standing postures and at different interaction distances. Targets in both small and large sizes were examined. Results showed that interaction distance yielded a significant effect on error rate, but the effect differed by task type. Little measurable difference was found in interaction performance, perceived usability and workload between sitting and standing postures. There were significant interaction effects between posture and interaction distance on perceived workload. Larger target size led to higher efficiency and accuracy in pointing tasks, but reduced accuracy in dragging tasks. This study provided implications that are likely to improve the design and deployment of large display-based freehand interaction techniques.


Assuntos
Análise e Desempenho de Tarefas , Carga de Trabalho , Humanos , Postura
19.
Appl Ergon ; 97: 103506, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34273814

RESUMO

A systematic review was conducted to examine the effects of interventions aimed at reducing the negative consequences of interruptions on task performance. Medline, PsycINFO, PsycARTICLES, and the ABI/INFORM Collection were searched for relevant publications. Thirty-three laboratory-based experiments, containing 49 interventions, were reviewed. Seven types of interventions were identified. Overall, the use of interventions significantly increased primary task accuracy (standardized mean difference (SMD) = 1.03, P = 0.001) and reduced resumption lag (SMD = -0.51, P < 0.001), whereas no significant difference was observed for interrupting task accuracy. Subgroup analyses indicated that intervention effects varied by (i) the type of intervention and (ii) the type of primary task (procedural, decision-making, or problem-solving tasks). The narrative synthesis provided additional evidence regarding interruption lag and time spent on a primary task. In sum, this review identified the types of interventions that were particularly effective and provided implications for application and further investigation.


Assuntos
Laboratórios , Análise e Desempenho de Tarefas , Humanos , Resolução de Problemas
20.
Cell Res ; 31(11): 1190-1198, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34376814

RESUMO

IL-15 is a promising cytokine to expand NK and CD8+ T cells for cancer immunotherapy, but its application is limited by dose-limiting, on-target off-tumor toxicity. Here, we have developed a next-generation IL-15 that is activated inside the tumor microenvironment (TME). This pro-IL-15 has the extracellular domain of IL-15Rß fused to the N-terminus of sIL-15-Fc through a tumor-enriched Matrix Metalloproteinase (MMP) cleavable peptide linker to block its activity. Unlike sIL-15-Fc, pro-IL-15 does not activate the peripheral expansion of NK cells and T cells, thus reducing systemic toxicity, but it still preserves efficient anti-tumor abilities. In various mouse tumors, the anti-tumor effect of pro-IL-15 depends on intratumoral CD8+ T cells and IFN-γ. Pro-IL-15 increases the stem-like TCF1+Tim-3-CD8+ T cells within tumor tissue and helps overcome immune checkpoint blockade (ICB) resistance. Moreover, pro-IL-15 synergizes with current tyrosine kinase inhibitor (TKI) targeted-therapy in a poorly inflamed TUBO tumor model, suggesting that pro-IL-15 helps overcome targeted-therapy resistance. Our results demonstrate a next-generation IL-15 cytokine that can stimulate potent anti-tumor activity without severe toxicity.


Assuntos
Interleucina-15 , Neoplasias , Animais , Linfócitos T CD8-Positivos , Citocinas , Imunoterapia , Camundongos , Neoplasias/tratamento farmacológico , Microambiente Tumoral
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