Browse Articles

pH-dependent dissociation from CTLA-4 in early endosomes improves both safety and antitumor activity of anti-CTLA-4 antibodies

Anti-CTLA-4 Abs (ACAs) are a breakthrough for cancer therapy, but their potential is limited by immunotherapy-related adverse events (irAE). We previously reported that ACAs with acidic pH-sensitive binding to CTLA-4 exhibit higher antitumor activity with fewer irAE. We now test a panel of variants of Ipilimumab (Ipi), the first ACA cancer therapeutic, for tumoricidal efficacy and irAE. Surprisingly, not all pH-sensitive Ipi variants exhibited an enhanced therapeutic index. Ipi13, which retained binding to CTLA-4 at pH 6.0 but dissociated at lower pH, showed no enhancement. By contrast, Ipi25, which dissociates from CTLA-4 at pH 6.0, the pH of the early endosome (EE), showed greater tumor regression and less severe irAE. Confocal microscopy showed that Ipi13 maintained colocalization with CTLA-4 at the late endosomes (LE) and lysosomes resulting in lysosomal degradation of CTLA-4. Conversely, Ipi25 did not colocalize with CTLA-4 in LE or lysosomes after endocytosis but allowed both proteins to transfer to recycling endosomes. EE dissociation was also characteristic of variants of Tremelimumab (Treme), another clinical ACA, that showed better efficacy and fewer side effects. Thus, our data reveal the significance of early intracellular dissociation from CTLA-4 to improve ACAs for safer and more effective cancer immunotherapy.

Separation of pups from their mother mice enhances odor associative learning at the late lactation stage

ATP-sensitive potassium channels alter glycolytic flux to modulate cortical activity and sleep

Metabolism plays a key role in the maintenance of sleep/wake states. Brain lactate fluctuations are a biomarker of sleep/wake transitions, where increased interstitial fluid (ISF) lactate levels are associated with wakefulness and decreased ISF lactate is required for sleep. ATP-sensitive potassium (K ATP ) channels couple glucose-lactate metabolism with excitability. Using mice lacking K ATP channel activity (e.g., Kir6.2 −/− mice), we explored how changes in glucose utilization affect cortical electroencephalography (EEG) activity and sleep/wake homeostasis. In the brain, Kir6.2 −/− mice shunt glucose toward glycolysis, reducing neurotransmitter biosynthesis and dampening cortical EEG activity. Kir6.2 −/− mice spent more time awake at the onset of the light period due to altered ISF lactate dynamics. Together, we show that Kir6.2-K ATP channels act as metabolic sensors to gate arousal by maintaining the metabolic stability of sleep/wake states and providing the metabolic flexibility to transition between states.

S100P is a core gene for diagnosing and predicting the prognosis of sepsis

Fungal-derived methyldeoxaphomins target <i>Plasmodium falciparum</i> segregation through the inhibition of PfActin1

Herein we report the finding and structure determination of a natural product based on the methyldeoxaphomin scaffold family from the fungus Trichocladium asperum that shows promising antiplasmodial activity and selectivity against host cells. In vitro evolution and whole genome analysis in Plasmodium falciparum with the most potent member, NPDG-F (EC 50 of 550 nM in Dd2; 290 nM in 3D7), shows that parasite resistance to methyldeoxaphomins is strongly associated with mutations in PfActin1 (PF3D7_1246200), a critically essential ATPase needed for all stages of parasite development. Molecular docking study with available PfActin1 crystal structure shows NPDG-F occupies the same allosteric binding pocket as the known actin inhibitor cytochalasin D. The direct PfActin1 target engagement in the allosteric site was supported by cross-resistance studies, isobologram analysis with other PfActin1 inhibitors, and the structure–activity relationships for the methyldeoxaphomin family. When added to in vitro culture, NPDG-F induced morphological abnormalities in merozoite cellularization during schizogony in both the Plasmodium blood and liver stages. Our data provide chemical validation that PfActin1 is an attractive, pan-lifecycle target and inform strategies for the design of more selective inhibitors.

Combined cerebrospinal fluid sCD163, MMP-9, with serum NCAM1 protein levels for predicting the prognosis of patients with tuberculous meningitis

PCSK9 potentiates innate immune response to RNA viruses by preventing AIP4-mediated polyubiquitination and degradation of VISA/MAVS

Upon viral infection, retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) detect viral RNA to initiate antiviral innate immune response, which is mediated by the mitochondrial adaptor protein VISA virus-induced signaling adaptor; also known as mitochondiral antiviral-signaling protein (MAVS). The stability and activity of VISA are tightly regulated by various posttranslational modifications, among which polyubiquitination plays important roles. Various E3 ubiquitin ligases, including atrophin interacting protein 4 (AIP4), mediate polyubiquitination of VISA and result in its degradation. However, how polyubiquitination of VISA is regulated remains unclear. Here, we uncovered a dual function for proprotein convertase subtilisin/kexin type 9 (PCSK9), a key enzyme in cholesterol homeostasis and a well-known therapeutic target in cardiovascular diseases, modulating host responses to RNA viruses both extracellularly and intracellularly. Secreted PCSK9 inhibited sendai virus (SeV) and vesicular stomatitis virus (VSV) infection, while the intracellular PCSK9 potentiated RLRs-mediated interferons (IFNs) induction by stabilizing VISA on mitochondria. Viral infection induced the translocation of PCSK9 to mitochondria where it competed with AIP4 for VISA, thereby inhibiting its polyubiquitination and degradation. Consequently, overexpression of PCSK9 enhanced VISA-mediated innate immune response against RNA viral infection, whereas its deficiency had the opposite effects and resulted in more robust replication of the virus. Pcsk9 −/− mice produced lower levels of type I IFNs and proinflammatory cytokines, rendering the increased sensitivity to VSV and influenza A virus infection. Altogether, our findings uncovered an important and unexpected role of PCSK9 in virus–host interaction and contribute to the understanding of the sophisticated mechanism governing the proper and efficient immune response to viral infection.

Evaluation of future land use change impacts on soil erosion for holota watershed, Ethiopia

Fluoride-based hydrogen bond chemistry in a layered double hydroxide cathode toward high-performance aqueous NH ₄ ⁺ storage

In aqueous ammonium-ion storage, hydrogen bonds play a pivotal role in the reversible insertion/extraction of NH 4 + within transition metal oxides/hydroxides. Although fluorine (F) is known for its strong electronegativity and potential to form robust hydrogen bonds with NH 4 + , its specific influence on NH 4 + storage remains unexplored. Herein, we systematically investigate the effects of F-based hydrogen bond chemistry within a layered double hydroxide matrix, where F species are introduced and subsequently partially removed via an electrochemical method. Our findings demonstrate that while increasing F doping content accelerates NH 4 + diffusion due to F’s strong electronegativity, it also triggers crystal shrinkage and depresses storage capacity. To this end, controlled partial removal of F, employing a lye-assistant electrochemical strategy, induces expanded interlayer spacing and distinct edge lattice tearing, thereby facilitating improved NH 4 + accommodation. The retained F sites couple with emerging exposed O sites maintain a high hydrogen bonding capability, which is further enhanced by the formation of highly active, curved hydroxyl groups centered around F sites. These manipulations significantly boost the NH 4 + storage performance of the electrode, providing insights into leveraging the strongest F-based hydrogen bond chemistry in developing high-performance ammonium-ion energy storage devices.

Efficacy of pre-harvest weed control treatments on onion bulb storability

Abstract Storage experiments were carried out, in 2019 and 2020, to evaluate the effect of pre-harvest weed control treatments on quality attributes and storability of onion bulbs during a six-month storage at room temperature (25 ± 5 °C and 50–60% relative humidity) in corrugated paper boxes. Weed control treatments consisted of the aqueous extracts of orange peel processing waste (OPPW) 20%, mango leaves waste (MLW) 30%, and olive oil processing waste (OOPW) 30%, alone or mixed with half a dose of oxyfluorfen herbicide (938 ml ha−1), soil mulching with orange peel processing waste, mango leaves, olive oil processing waste, and rice straw (OPPWM, OOPWM, MLW, and RSM, respectively) at 10 tons ha−1, hoeing, oxyfluorfen herbicide (at 938 and 1875 ml ha−1), and an unweeded control treatment. OPPW mulch and hoeing treatments were the most effective treatments in improving storability, decreasing weight loss and decay percentages of onion bulbs as well as maintaining bulb quality attributes, i.e., bulb firmness, dry matter, total soluble solids and total soluble sugars content during a six-months storage. It was concluded that using OPPW and MLW, as soil mulches or as aqueous extracts, for weed control within onion field, helps maintain onion bulb quality, and storability.

Global diversity and energy of animals shaping the Earth’s surface

The collective influence of animals on the processes shaping the Earth’s surface remains largely unknown, with most studies limited to individual species and well-known exemplars. To establish the global geomorphic significance of animals, we systematically reviewed and synthesized evidence across freshwater and terrestrial ecosystems. Over 600 animal taxa had reported geomorphic effects. For the 495 wild animals and 5 livestock identified to species level, we estimated their global abundance, and collective biomass and energy. While our census is global in scope, a lack of research in the tropics and subtropics, and on less visible animals, leaves them underrepresented in analyses. Most reported species are globally widespread, but some are rare, endemic, and/or threatened, leading to risks that key geomorphic processes cease before we fully understand them. We estimate the collective biomass in wild animal geomorphic agents at ≈0.2 Mt Carbon, equating to a biological energy content of ≈7.6 million GJ. If a conservative minimum 1% of this energy contributes to geomorphic work annually, this yields an energy contribution from wild animal geomorphic agents of ≈76,000 GJ—equivalent to the energy of hundreds of thousands of extreme floods. Uncertainties in biomass estimates and energy partitioning mean this value could credibly be an order of magnitude higher, and countless species remain unreported or undiscovered. The livestock estimates exceed the wild animals estimates by three orders of magnitude. The geomorphic energy of animals is far more influential than previously recognized and future losses, dispersal and introductions of zoogeomorphic species may induce substantive landscape changes.

Statistical inference of the generalized process capability index for the discrete lindley distribution

Illuminating an invisible state of the HIV-1 capsid protein CTD dimer using ¹⁹ F NMR and weighted ensemble simulations

The HIV-1 capsid protein (CA) assembles into a conical shell during viral maturation, encasing and protecting the viral RNA genome. The C-terminal domain (CTD) of the two-domain capsid protein dimerizes, and this dimer connects individual chains in the mature capsid lattice. Previous NMR studies have shown that different dimer arrangements can be formed by isolated capsid protein chains and in assembled capsid lattices; however, the dynamics and functional relevance of these alternate dimers are unknown. To explore the conformational landscape of the CA-CTD dimer, we carried out atomistic molecular dynamics simulations using the weighted ensemble path sampling strategy, generating an ensemble of conformations. Focusing on the two dimer forms previously observed via solution NMR, we refined the conformational ensemble to highlight two metastable states using a Markov state model. Experimentally, we measured the interconversion rates between the two alternate dimers using 19 F NMR, and these rates showed good agreement with the interconversion rates derived from the simulations. After identifying the key interactions that distinguish the dimer states, the alternate dimer was further experimentally verified through disulfide crosslinking. Our results demonstrate the advantages of pairing weighted ensemble path sampling with 19 F NMR to gain atomistic insights into the hidden dimer state of the HIV-1 capsid protein.

Multiomics in silico analysis identifies TM4SF4 as a cell surface target in hepatocellular carcinoma

The clinical application of cellular immunotherapy in hepatocellular carcinoma (HCC) is impeded by the lack of a cell surface target frequently expressed in HCC cells and with minimal presence in normal tissues to reduce on-target, off-tumor toxicity. To address this, an in silico multomics analysis was conducted to identify an optimal therapeutic target in HCC. A longlist of genes (n = 12,948) expressed in HCCs according to The Human Protein Atlas database were examined. Eight genes were shortlisted to identify one with the highest expression in HCCs, without being shed into circulation, and with restrictive expression profile in other normal human tissues. A total of eight genes were shortlisted and subsequently ranked according to the combination of their transcript and protein expression levels in HCC cases (n = 791) derived from four independent datasets. TM4SF4 was the top-ranked target with the highest expression in HCCs. TM4SF4 showed more favorable expression profile with significantly lower expression in normal human tissues but more highly expressed in HCC compared with seven other common HCC therapeutic targets. Furthermore, scRNA-seq and immunohistochemistry datasets showed that TM4SF4 was absent in immune cell populations but highly expressed in the bile duct canaliculi of hepatocytes, regions inaccessible to immune cells. In scRNA-seq dataset of HCCs, TM4SF4 expression was positively associated with mitochondrial components and oxidative phosphorylation Gene Ontologies in HCC cells (n = 15,787 cells), suggesting its potential roles in mitochondrial-mediated oncogenic effects in HCC. Taken together, TM4SF4 is proposed as a promising cell surface target in HCC due to its high expression in HCC cells with restricted expression profile in non-cancerous tissues, and association with HCC oncogenic pathways.

Enhancing resilience of distributed DC microgrids against cyber attacks using a transformer-based Kalman filter estimator

Fungal effector disables cathepsin-driven Toll immunity in insects

Plasma attenuates endothelial injury compared to crystalloids in a ventilated rat pneumosepsis model

Background The dysregulated immune response during sepsis involves endothelial injury, which may be augmented by infusion of clear fluids such as crystalloids. Plasma has been suggested as an alternative resuscitation fluid but it is unclear whether previously observed benefits were due to the type of fluid, or due to less volume required to restore tissue perfusion. We hypothesized that resuscitation with plasma reduces endothelial injury, inflammation, and organ injury compared to similar and higher volumes of crystalloids in a rat pneumosepsis model. Methods Rats were intratracheally inoculated with Streptococcus Pneumoniae to induce pneumosepsis. Twenty-four hours after inoculation, animals were randomized to 4 groups: healthy controls (non-resuscitated, n = 6), 10 ml/kg/hr (standard-volume, n = 11) crystalloid resuscitation, 3.33 ml/kg/hr (low-volume, n = 11) crystalloid resuscitation or 3.33 ml/kg/hr plasma resuscitation (n = 11). Plasma markers of inflammation and endothelial injury were measured. Organs were harvested for histology and wet-to-dry weight ratio determination. Results Inoculated animals developed pneumosepsis, with lower mean arterial pressures (p &lt; 0.001) and higher lactate levels (p &lt; 0.001) compared to healthy controls. Animals resuscitated with plasma showed a trend towards lower syndecan-1 levels compared to the standard-volume crystalloid group (82 vs 99 ng/mL, p = 0.06) and had lower levels of VCAM-1 (424 vs 592 ng/mL, p &lt; 0.01) compared to the standard volume crystalloid group, but not when compared to the low-volume crystalloid group. Other markers of endothelial injury or inflammation were not significantly different between groups. No significant differences were observed in histologic injury scores and wet-to-dry ratios. Conclusion Plasma resuscitation modestly reduces endothelial injury compared to crystalloid resuscitation. This effect might be attributed to decreased resuscitation volumes rather than the type of fluid.

Sleep and stress in athletes with disabilities around the 2021 Tokyo Paralympic games during the pandemic

Extensive location bias of the GPCR-dependent translatome via site-selective activation of mTOR

G protein–coupled receptors (GPCRs) modulate various physiological functions by rewiring cellular gene expression in response to extracellular signals. Control of gene expression by GPCRs has been studied almost exclusively at the transcriptional level, neglecting an extensive amount of regulation that takes place translationally. Hence, little is known about the nature and mechanisms of gene-specific posttranscriptional regulation downstream of receptor activation. Here, we apply an unbiased multiomics approach to delineate an extensive translational regulatory program initiated by the prototypical beta2-adrenergic receptor (β2-AR) and provide mechanistic insights into how these processes are orchestrated. Using ribosome profiling (Ribo-seq), we identify nearly 120 gene targets of adrenergic receptor activity for which expression is exclusively regulated at the level of translation. We next show that all translational changes are induced selectively by endosomal β2-ARs and report that this proceeds through activation of the mammalian target of rapamycin (mTOR) pathway. Specifically, within the set of translational GPCR targets, we find significant enrichment of genes with 5’ terminal oligopyrimidine (TOP) motifs, a gene class classically known to be translationally regulated by mTOR. We then demonstrate that endosomal β2-ARs are required for mTOR activation and subsequent mTOR-dependent TOP mRNA translation. This site-selective crosstalk between the pathways is observed in multiple cell models with native β2-ARs, across a range of endogenous and synthetic adrenergic agonists, and for other GPCRs with intracellular activity. Together, this comprehensive analysis of drug-induced translational regulation establishes a critical role for location-biased GPCR signaling in fine-tuning the cellular protein landscape.

Transcriptomic adaptation of skeletal muscle in response to MICT and HIIT exercise modalities

Skeletal muscle exhibits remarkable plasticity in response to diverse stimuli, with exercise serving as a potent trigger. Varied exercise modalities, including moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT), induce distinct structural and functional adaptations on skeletal muscle. However, the underlying molecular mechanisms governing these adaptations remain poorly understood. In this study, we utilized RNA-seq to characterize the transcriptomic profile of murine gastrocnemius muscle following 8-week treadmill-based MICT (M group) and HIIT (H group). A total of 1052 DEGs were screened in H vs. M. Among the top 10 significant DEGs, Foxo1 and Myod1 are closely related to muscular physiology. Through KEGG pathway analysis, distinct adaptations were primarily identified in the FoxO, MAPK, and PI3K-AKT pathways. By analyzing the expression of myokines, a significantly higher Igf-1 expression level was observed in the M group compared to the H group. Therefore, IGF-1, a well-known upstream regulator of both the PI3K-AKT-FoxO and MAPK pathways, might drive distinct muscle adaptations through variations in Igf-1 expression induced by these two exercise modalities.