Active State Research Articles

Hand LightWeightNet: an optimized hand pose estimation for interactive mobile interfaces

In this paper, a hand pose estimation method is introduced that combines MobileNetV3 and CrossInfoNet into a single pipeline. The proposed approach is tailored for mobile phone processors through optimizations, modifications, and enhancements made to both architectures, resulting in a lightweight solution. MobileNetV3 provides the bottleneck for feature extraction and refinements while CrossInfoNet benefits the proposed system through a multitask information sharing mechanism. In the feature extraction stage, we utilized an inverted residual block that achieves a balance between accuracy and efficiency in limited parameters. Additionally, in the feature refinement stage, we incorporated a new best-performing activation function called “activate or not” ACON, which demonstrated stability and superior performance in learning linearly and non-linearly gates of the whole activation area of the network by setting hyperparameters to switch between active and inactive states. As a result, our network operated with 65% reduced parameters, but improved speed by 39% which is suitable for running in a mobile device processor. During experiment, we conducted test evaluation on three hand pose datasets to assess the generalization capacity of our system. On all the tested datasets, the proposed approach demonstrates consistently higher performance while using significantly fewer parameters than existing methods. This indicates that the proposed system has the potential to enable new hand pose estimation applications such as virtual reality, augmented reality and sign language recognition on mobile devices.

Abstract 6444: Assessing cytotoxic T cell responses to immune checkpoint inhibitors in murine and human tumor samples using metabolic imaging

Abstract Background Immune checkpoint inhibitors (ICI) have revolutionized cancer treatment. Unfortunately, existing FDA approved biomarkers do not accurately predict which patients will respond. The Elephas Cybrid™ platform aims to improve ICI response prediction by imaging a patient’s biopsy treated with ICI ex vivo. Multiphoton microscopy (MPM) is a powerful imaging technique to interrogate the biological changes in live tumor fragments (LTFs) following ICI treatment. MPM allows rapid visualization of biological processes in 3D living tissues in a non-destructive fashion allowing for longitudinal assessment of a sample. We and others have used label-free metabolic imaging to demonstrate that changes in T cell metabolism and activation status are correlated. Using MPM imaging we successfully demonstrated T cell activation and T cell mediated cytotoxicity in response to ICI in LTFs and tumor biopsies. Methods Tumors were cut into LTFs, sorted, and cultured using the Cybrid platform. LTF structure and metabolic status were assessed using intrinsically fluorescent NAD(P)H and FAD. Anti-CD8 nanobodies and cleaved caspase 3/7 dye were used to characterize T cell cytotoxicity. Multi-channel fluorescence intensity and lifetime were obtained over 48 hours using MPM. Results Murine CT26 LTFs generated with the Cybrid platform were treated with ICI and cytotoxicity was assessed in the intact LTFs by monitoring caspase 3/7 activity using MPM over 48 hours. We found that ICI treatment resulted in a significant increase in caspase 3/7 activity compared to control treated LTFs. By blocking the interaction of T cells with tumor cells through antibody blockade, we demonstrated that the cytotoxicity observed was T cell mediated. As additional confirmation, we measured changes in cytotoxicity in the ICI resistant LLC1 tumor model. As expected, we did not observe an increase in cytotoxicity in LLC1 LTFs treated with ICI. MPM allows for the tracking of labeled T cells and characterization of their metabolism as a means of assessing changes in their activation state. We used a CD8 nanobody to label T cells in CT26 LTFs and then characterized the shift in metabolism following ICI treatment. Finally, we applied the Cybrid platform to human biopsies treated with ICI and characterized the cytotoxicity and shifts in T cell metabolism in living tissue. These data show that the Cybrid platform can measure changes in T cell metabolism and T cell cytotoxicity in response to ICI in 3D living tissue. Conclusions The methods presented herein will advance the field of cancer diagnostics by progressing from fixed tissue imaging and genetic characterization to the assessment of clinically relevant ICI-treated biopsies. Understanding the response of biopsies to immunotherapies will allow clinicians to make more informed treatment decisions and improve the lives of those with cancer. Citation Format: Jonathan Ouellette, Janey Degnan, Anna Kellner, Evan Flietner, Lindsay Doebert, Zachary Swider, Eric Wait, Victoria Pope, Laura Hrycyniak, Sean Caenepeel, Kevin Eliceiri, T S. Ramasubramanian, Michael J. Korrer. Assessing cytotoxic T cell responses to immune checkpoint inhibitors in murine and human tumor samples using metabolic imaging [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6444.

Plasma metabolomic profile is near-normal in people with HIV on long-term suppressive antiretroviral therapy.

Combination antiretroviral therapy (ART) has transformed human immunodeficiency virus (HIV) infection in people with HIV (PWH). However, a chronic state of immune activation and inflammation is maintained despite achieving HIV suppression and satisfactory immunological recovery. We aimed to determine whether the plasma metabolomic profile of PWH on long-term suppressive ART and immunologically recovered approximates the normality by comparison with healthy controls with similar age and gender. We carried out a cross-sectional study in 17 PWH on long-term ART (HIV-RNA <50 copies/mL, CD4+ ≥500 cells/mm3, and CD4+/CD8+ ≥1) and 19 healthy controls with similar age and gender. Metabolomics analysis was performed by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS). The statistical association analysis was performed by principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and Generalized Linear Models (GLM) with a gamma distribution (log-link). Significance levels (p-value) were corrected for multiple testing (q-value). PCA and PLS-DA analyses found no relevant differences between groups. Adjusted GLM showed 14 significant features (q-value<0.20), of which only three could be identified: lysophosphatidylcholine (LysoPC) (22:6) (q-value=0.148), lysophosphatidylethanolamine (LysoPE) (22:6) (q-value=0.050) and hydroperoxy-octadecatrienoic acid (HpOTrE)/dihydroperoxy-octadecatrienoic acid (DiHOTrE)/epoxy-octadecadienoic acid (EpODE) (q-value=0.136). These significant identified metabolites were directly correlated to plasma inflammatory biomarkers in PWH and negatively correlated in healthy controls. PWH on long-term ART have a metabolomic profile that is almost normal compared to healthy controls. Nevertheless, residual metabolic alterations linked to inflammatory biomarkers persist, which could favor the development of age-related comorbidities among this population.

Transcriptional control of neural stem cell activity.

In the adult brain, neural stem cells (NSCs) are under the control of various molecular mechanisms to produce an appropriate number of neurons that are essential for specific brain functions. Usually, the majority of adult NSCs stay in a non-proliferative and undifferentiated state known as quiescence, occasionally transitioning to an active state to produce newborn neurons. This transition between the quiescent and active states is crucial for the activity of NSCs. Another significant state of adult NSCs is senescence, in which quiescent cells become more dormant and less reactive, ceasing the production of newborn neurons. Although many genes involved in the regulation of NSCs have been identified using genetic manipulation and omics analyses, the entire regulatory network is complicated and ambiguous. In this review, we focus on transcription factors, whose importance has been elucidated in NSCs by knockout or overexpression studies. We mainly discuss the transcription factors with roles in the active, quiescent, and rejuvenation states of adult NSCs.

Observed soil arching-induced ground deformation and stress redistribution behind braced excavation

This paper presents observed arching-induced ground deformation and stress redistribution behind braced excavation using the top-down construction method. The soil properties around the excavation were determined by laboratory and field tests. The ground deformation, soil displacement vector, strain path, principal strain, maximum shear strain, lateral earth pressure, pore water pressure, and effective stress path are presented based on the measured data. The majority of soil behind the wall is under volumetric expansion, indicating consolidation, creep behavior, or a combination of both. Besides, two periods of increases in pore pressure are observed, due to stress transfer from the lower to the upper parts (i.e. soil arching effect). The deep inward movement of the wall and the nearby soil accounts for the distribution of lateral earth pressure acting on the wall. The soil located behind the area of maximum wall deformation and adjacent to the wall, as well as the soil below the excavation base intersected by the shear plane, is in an active stress state. The lateral earth pressure at 5 m from the left excavation wall showed minimal changes, due to the combined effects of soil arching from lateral excavation and shield tunneling.

Molecular basis of JAK2 activation in erythropoietin receptor and pathogenic JAK2 signaling.

Janus kinase 2 (JAK2) mediates type I/II cytokine receptor signaling, but JAK2 is also activated by somatic mutations that cause hematological malignancies by mechanisms that are still incompletely understood. Quantitative superresolution microscopy (qSMLM) showed that erythropoietin receptor (EpoR) exists as monomers and dimerizes upon Epo stimulation or through the predominant JAK2 pseudokinase domain mutations (V617F, K539L, and R683S). Crystallographic analysis complemented by kinase activity analysis and atomic-level simulations revealed distinct pseudokinase dimer interfaces and activation mechanisms for the mutants: JAK V617F activity is driven by dimerization, K539L involves both increased receptor dimerization and kinase activity, and R683S prevents autoinhibition and increases catalytic activity and drives JAK2 equilibrium toward activation state through a wild-type dimer interface. Artificial intelligence-guided modeling and simulations revealed that the pseudokinase mutations cause differences in the pathogenic full-length JAK2 dimers, particularly in the FERM-SH2 domains. A detailed molecular understanding of mutation-driven JAK2 hyperactivation may enable novel therapeutic approaches to selectively target pathogenic JAK2 signaling.

Thermal conductivity and structural behavior of confined H2 from molecular dynamics simulation

In this work, we perform equilibrium molecular dynamics simulation to study the thermal conductivity of hydrogen molecules (H2) under extreme confinement within graphene nanochannel. We analyze the structural behavior of H2 molecules inside the nanochannel and also examine the effect of nanochannel height, the number of H2 molecules, and temperature of the system on the thermal conductivity. Our results reveal that H2 molecules exhibit a strong propensity for absorption onto the nanochannel wall, consequently forming a dense packed layer in close to the wall. This phenomenon significantly impacts the thermal conductivity of the confined system. We made a significant discovery, revealing a strong correlation between the mass density near the nanochannel wall and the thermal conductivity. This finding highlights the crucial role played by the density near the wall in determining the thermal conductivity behavior. Surprisingly, the average thermal conductivity for nanochannels with a height (h) less than 27 Å exhibited an astonishing increase of over 12 times when compared to the bulk. Moreover, we observe that increasing the nanochannel height, while the number of H2 molecules fixed, leads to a notable decrease in thermal conductivity. Furthermore, we investigate the influence of temperature on thermal conductivity. Our simulations demonstrate that higher temperature enhance the thermal conductivity due to increased phonon activity and energy states, facilitating more efficient heat transfer and higher thermal conductivity. To gain deeper insights into the factors affecting thermal conductivity, we explored the phonon density of states. Studying the behavior of hydrogen in confined environments can offer valuable insights into its transport properties and its potential for industrial applications.

EEG as a potential ground truth for the assessment of cognitive state in software development activities: A multimodal imaging study.

Cognitive human error and recent cognitive taxonomy on human error causes of software defects support the intuitive idea that, for instance, mental overload, attention slips, and working memory overload are important human causes for software bugs. In this paper, we approach the EEG as a reliable surrogate to MRI-based reference of the programmer's cognitive state to be used in situations where heavy imaging techniques are infeasible. The idea is to use EEG biomarkers to validate other less intrusive physiological measures, that can be easily recorded by wearable devices and useful in the assessment of the developer's cognitive state during software development tasks. Herein, our EEG study, with the support of fMRI, presents an extensive and systematic analysis by inspecting metrics and extracting relevant information about the most robust features, best EEG channels and the best hemodynamic time delay in the context of software development tasks. From the EEG-fMRI similarity analysis performed, we found significant correlations between a subset of EEG features and the Insula region of the brain, which has been reported as a region highly related to high cognitive tasks, such as software development tasks. We concluded that despite a clear inter-subject variability of the best EEG features and hemodynamic time delay used, the most robust and predominant EEG features, across all the subjects, are related to the Hjorth parameter Activity and Total Power features, from the EEG channels F4, FC4 and C4, and considering in most of the cases a hemodynamic time delay of 4 seconds used on the hemodynamic response function. These findings should be taken into account in future EEG-fMRI studies in the context of software debugging.

Neuronal deletion of Gtf2i results in developmental microglial alterations in a mouse model related to Williams syndrome.

Williams syndrome (WS) is a genetic neurodevelopmental disorder caused by a heterozygous microdeletion, characterized by hypersociability and unique neurocognitive abnormalities. Of the deleted genes, GTF2I has been linked to hypersociability in WS. We have recently shown that Gtf2i deletion from forebrain excitatory neurons, referred to as Gtf2i conditional knockout (cKO) mice leads to multi-faceted myelination deficits associated with the social behaviors affected in WS. These deficits were potentially mediated also by microglia, as they present a close relationship with oligodendrocytes. To study the impact of altered myelination, we characterized these mice in terms of microglia over the course of development. In postnatal day 30 (P30) Gtf2i cKO mice, cortical microglia displayed a more ramified state, as compared with wild type (controls). However, postnatal day 4 (P4) microglia exhibited high proliferation rates and an elevated activation state, demonstrating altered properties related to activation and inflammation in Gtf2i cKO mice compared with control. Intriguingly, P4 Gtf2i cKO-derived microglial cells exhibited significantly elevated myelin phagocytosis invitro compared to control mice. Lastly, systemic injection of clemastine to P4 Gtf2i cKO and control mice until P30, led to a significant interaction between genotypes and treatments on the expression levels of the phagocytic marker CD68, and a significant reduction of the macrophage/microglial marker Iba1 transcript levels in the cortex of the Gtf2i cKO treated mice. Our data thus implicate microglia as important players in WS, and that early postnatal manipulation of microglia might be beneficial in treating inflammatory and myelin-related pathologies.

Drug Repurposing and Personalized Treatment Strategies for Bipolar Disorder Using Transcriptomic.

The present study combined transcriptomic data and computational techniques based on gene expression signatures to identify novel bioactive compounds or FDA-approved drugs for the management of Bipolar Disorder (BD). Five transcriptomic datasets, comprising a total of 165 blood samples from BD case-control, were selected from the Gene Expression Omnibus repository (GEO). The number of subjects varied from 6 to 60, with a mean age ranging from 35 to 48, with a gender variation between them. Most of the patients were on pharmacological treatment. Master Regulator Analysis (MRA) and Gene Set Enrichment Analysis (GSEA) were performed to identify statistically significant genes between BD and HC and their association with the mood states of BD. Additionally, existing molecules with the potential to reverse the transcriptomic profiles of disease-altered regulons in BD were identified using the LINCS and cMap databases. MRA identified 59 potential MRs candidates modulating the regulatory units enriched with genes altered in BD, while the GSEA identified 134 enriched genes, and a total of 982 regulons had their activation state determined. Both analyses showed genes exclusively associated with mania, depression, or euthymia, and some genes were common between the three mood states. We identified bioactive compounds and licensed drug candidates, including antihypertensives and antineoplastics, as promising candidates for treating BD. Nevertheless, experimental validation is essential to authenticate these findings in subsequent studies. Although preliminary, our data provides some insights regarding the biological patterns of BD into distinct mood states and potential therapeutic targets. The combined transcriptomic and bioinformatics strategy offers a route to advance drug discovery and personalized medicine by tapping into gene expression information.

Role of dopamine in regulating microglia inflammatory responses through TLR4-NFb pathway

Parkinsons disease (PD) is a prevalent neurodegenerative disorder that affects a significant portion of the population. One of its distinguishing features is the gradual loss of dopaminergic cells in a specific region of the brain known as the substantia nigra. In recent years, researchers have uncovered that neuroinflammation facilitates the developmental process of PD. Specifically, studies have shown that the activation of microglia, the brains immune cells, is closely linked to the levels of dopamine secreted by neurons. However, the influence of dopamine on activated microglia in PD has not been fully explored. In this study, we aimed to explore the impact of dopamine on activated microglia. To establish an activated microglia model, we used BV-2 cell lines and treated them with lipopolysaccharide (LPS) at a concentration of 200 ng/ml. Two separate groups were then exposed to dopamine at concentrations of 2 M and 10 M, respectively, to simulate dopamine treatment in the brain. To assess the effects of dopamine, we performed real-time PCR to measure the relative mRNA levels of pro- and anti-inflammatory cytokines, conducted immunofluorescent staining to observe and analyze the cell morphology, carried out a phagocytosis assay to assess the cells phagocytic ability, and conducted western blotting to identify the specific pathway through which dopamine affects microglia activation. Our findings revealed that dopamine can modulate the activation state of microglia and reduce the cells inflammatory responses via the TLR4-NFB pathway. This suggests that dopamine has the potential to alleviate neuroinflammation in PD, opening up new avenues for future treatments and therapies.

Overnight neuronal plasticity and adaptation to emotional distress.

Expressions such as 'sleep on it' refer to the resolution of distressing experiences across a night of sound sleep. Sleep is an active state during which the brain reorganizes thesynaptic connections that form memories. This Perspective proposes a model of how sleep modifies emotional memory traces. Sleep-dependent reorganization occurs through neurophysiological events in neurochemical contexts that determine the fates of synapses to grow, to survive or to be pruned. We discuss how low levels of acetylcholine during non-rapid eye movement sleep and low levels of noradrenaline during rapid eye movement sleep provide a unique window of opportunity for plasticity in neuronal representations of emotional memories that resolves the associated distress. We integrate sleep-facilitated adaptation over three levels: experience and behaviour, neuronal circuits, and synaptic events. The model generates testable hypotheses for how failed sleep-dependent adaptation to emotional distress is key to mental disorders, notably disorders of anxiety, depression and post-traumatic stress with the common aetiology of insomnia.

NASP gene contributes to autism by epigenetic dysregulation of neural and immune pathways

BackgroundEpigenetics makes substantial contribution to the aetiology of autism spectrum disorder (ASD) and may harbour a unique opportunity to prevent the development of ASD. We aimed to identify novel epigenetic...

Abstract IA007: Distinct immune landscapes characterize highly and minimally invasive brain metastases

Abstract IA007: Distinct immune landscapes characterize highly and minimally invasive brain metastases

Does artificial intelligence need companionship to assist in drug discovery? The Kirsten rat sarcoma virus study

Abstract In this Opinion article, we confront the role of artificial intelligence (AI) in targeting and understanding resistance to targeted therapy using the most frequently mutated oncoprotein family in human cancer, rat sarcoma virus guanosine triphosphate hydrolases (RAS GTPases), here Kirsten RAS (KRAS), as an example. Aberrant regulation of the active GTP-bound state of KRAS is associated with tumourigenesis, aggressive disease, and poor prognosis. KRAS mutations (eg, G12C, G12D, G12V, G13D, inter al.) are drivers of numerous cancer types, including non-small cell lung, colorectal, and pancreatic cancers. These mutations have shown to play a significant role in cell behaviour and response to treatment. Since its discovery in the 1980s, it has been recognized that over-expression of KRAS and other RAS family members induces resistance to radiotherapy. Moreover, over the years preclinical and clinical studies showed that tumours with KRAS mutations exhibit different treatment sensitivities compared to tumours with wild-type KRAS.

Abstract P34: Bayesian networks modeling identifies a reliance of TP53 mutant AML on NF kappa B signaling

Abstract In acute myeloid leukemia (AML), TP53 mutations ( TP53Mut ) confer the worst prognosis. Leukemia stem cells (LSCs) are rare AML cells endowed with self-renewal capacity, allowing them to recapitulate leukemia after therapy and cause disease progression. In human AML, signaling pathways associated with inflammation have been implicated in the pathogenesis of TP53Mut AML, but the pathways that mediate self-renewal in human TP53Mut AML are not well-known. To define the signaling pathways that are activated in TP53Mut human LSCs, we used CyTOF, a form of flow cytometry that can measure up to 40 proteins simultaneously at single-cell resolution. We compared the levels of activated signaling molecules in the LSC-enriched (CD34+CD38−) subset of seven TP53Mut and seven TP53 wild-type ( TP53WT ) AML samples. Phosphorylated NF kappa B (pNFkB), pSTAT1, and pP38 are significantly higher in TP53Mut AMLs. In contrast, Ki67 and pMAPKAPKII are higher in TP53WT AML. These data demonstrate a unique signaling activation state in TP53Mut AML. The influence of signaling molecules on downstream targets can vary by cellular context. Therefore, we asked whether the influence and interaction of the activated signaling molecules vary between TP53Mut and TP53WT LSCs. To model the signaling architecture, we performed Bayesian networks modeling, a machine learning algorithm that has been validated as a method to discover statistical correlations and dependencies between signaling molecules. We found a similar global signaling network structure and hierarchy in TP53Mut and TP53WT AMLs. However, TP53Mut model showed NFkB have strong influences on phosphorylated Histone H3 (pHIS3) and Ki67, suggesting that proliferation depends on NFkB levels in TP53Mut LSCs. Furthermore, NFkB levels were highly dependent on pSTAT1 in TP53Mut LSCs. Next, we compared the transcriptional profiles of TP53Mut and TP53WT samples in the BEAT AML dataset and found that TP53Mut AML displayed significant enrichment of all the NFkB gene sets (n=19) in the molecular signatures database, providing more evidence for a unique reliance of TP53Mut human AML on NFkB signaling. Therefore, we used lentivirus transduced shRNA constructs to determine the influence of mutant p53 on signaling in human AML. We found that knockdown of TP53Mut reduced NFkB protein levels in Kasumi AML cells (which are TP53R248Q/ − ) but not in MOLM13 AML cells (which are TP53WT). RNA sequencing of transduced Kasumi cells showed that TP53Mut knockdown led to loss of NFkB and LSC self-renewal signatures. Knockdown of TP53Mut in primary human TP53Mut AMLs (S127F/- and S241Y/-) led to a similar loss of NFkB and LSC signatures in these primary samples as well. Colony formation in Kasumi cells and TP53Mut primary human AML were also abrogated after TP53Mut knockdown. These data show TP53Mut promotes NFkB activation in human AML and suggests that human TP53Mut LSCs may be dependent on NFkB for self-renewal. These data implicate NFkB as a possible therapeutic strategy to target TP53Mut human LSCs. Citation Format: Daniel Chang, Klara Noble-Orcutt, Marie Lue Antony, Yoonkyu Lee, Fiona He, Karen Sachs, Chad L Myers, Zohar Sachs. Bayesian networks modeling identifies a reliance of TP53 mutant AML on NF kappa B signaling [abstract]. In: Proceedings of the Blood Cancer Discovery Symposium; 2024 Mar 4-6; Boston, MA. Philadelphia (PA): AACR; Blood Cancer Discov 2024;5(2_Suppl):Abstract nr P34.

Metabolic response of auditory brainstem neurons to their broad physiological activity range.

Neurons exhibit a high energetic need, and the question arises as how they metabolically adapt to changing activity states. This is relevant for interpreting functional neuroimaging in different brain areas. Particularly, neurons with a broad firing range might exhibit metabolic adaptations. Therefore, we studied MNTB (medial nucleus of the trapezoid body) principal neurons, which generate action potentials (APs) at frequencies up to several hundred hertz. We performed the experiments in acute brainstem slices of the Mongolian gerbil (Meriones unguiculatus) at 22.5-24.5°C. Upon electrical stimulation of afferent MNTB fibres with 400 stimuli at varying frequencies, we monitored autofluorescence levels of NAD(P)H and FAD and determined the extremum amplitudes of their biphasic response. Additionally, we compared these data with alterations in O2 concentrations measured with an electrochemical sensor. These O2 changes are prominent since MNTB neurons rely on oxidative phosphorylation as shown by our pharmacological experiments. We calculated the O2 consumption rate as change in O2 concentration divided by stimulus durations, because these periods varied inversely with stimulus frequency as a result of the constant number of 400 stimuli applied. The O2 consumption rate increased with stimulation frequency up to a constant value at 600 Hz; that is, energy demand depends on temporal characteristics of activity despite the same number of stimuli. The rates showed no correlation with peak amplitudes of NAD(P)H or FAD, whilst the values of the two molecules were linearly correlated. This points at the complexity of analysing autofluorescence imaging for quantitative metabolic studies, because these values report only relative net changes of many superimposed oxidative and reductive processes. Monitoring O2 concentration rates is, thus, an important tool to improve the interpretation of NAD(P)H/FAD autofluorescence data, as they do not under all conditions and in all systems appropriately reflect the metabolic activity or energy demand.

Site-specific regulation of Th2 differentiation within lymph node microenvironments.

T helper 2 (Th2) responses protect against pathogens while also driving allergic inflammation, yet how large-scale Th2 responses are generated in tissue context remains unclear. Here, we used quantitative imaging to investigate early Th2 differentiation within lymph nodes (LNs) following cutaneous allergen administration. Contrary to current models, we observed extensive activation and "macro-clustering" of early Th2 cells with migratory type-2 dendritic cells (cDC2s), generating specialized Th2-promoting microenvironments. Macro-clustering was integrin-mediated and promoted localized cytokine exchange among T cells to reinforce differentiation, which contrasted the behavior during Th1 responses. Unexpectedly, formation of Th2 macro-clusters was dependent on the site of skin sensitization. Differences between sites were driven by divergent activation states of migratory cDC2 from different dermal tissues, with enhanced costimulatory molecule expression by cDC2 in Th2-generating LNs promoting prolonged T cell activation, macro-clustering, and cytokine sensing. Thus, the generation of dedicated Th2 priming microenvironments through enhanced costimulatory molecule signaling initiates Th2 responses in vivo and occurs in a skin site-specific manner.

Increased expression of omentin-1 is associated with synovitis and bone destruction in rheumatoid arthritis.

The aberrant expression of omentin-1 had been reported in type 2 diabetes and cardiovascular disease. Here, we investigated the expression and role of omentin-1 in rheumatoid arthritis (RA). The expression of omentin-1 in RA and in the normal population was detected by ELISA and immunohistochemistry, and collagen-induced arthritis (CIA) mice were used to detect the role of omentin-1 in RA. We found that the expression of omentin-1 was elevated in serum of RA patients compared with healthy controls (p=0.004), and in the RA disease activity group compared with the disease remission group (p<0.001). In addition, the level of omentin-1 in RA patients was positively correlated with CRP (r=0.427, p=0.002), ESR (r=0.454, p<0.001) and DAS28 (r=0.496, p<0.001; r=0.661, p<0.001, respectively). Multivariable analysis showed that omentin-1 alone was associated with disease activity state (OR=1.018, p=0.004). Immunohistochemical results showed that omentin-1 was increased in the synovium of RA and CIA mice. Omentin-1 injection resulted in an earlier onset of arthritis, an aggravated arthritic progression, more severe synovial hyperplasia and bone erosion in CIA mice. Moreover, omentin-1 treatment markedly enhanced IL-6, TNF-α, MMP-3, MMP-13 and RANKL in the joint tissue of CIA mice. Our results suggested that omentin-1 was up-regulated in RA and can exacerbate synovitis and joint destruction which may provide new insight into the pathogenesis of RA.

The Fermi-LAT view of the changing-look blazar OQ 334

Unusually, there are still certain characteristics of the changing-look (CL) active galactic nuclei (AGNs) that remain undetected. Consequently, the trigger mechanism behind the CL phenomenon observed in partial AGNs remains unknown. We explore the light curve and spectral energy distribution (SED) of the CL blazar OQ 334 as obtained by Fermi -LAT. By examining the variability of the equivalent width (EW), we categorise the Fermi -LAT light curves of OQ 334 during the epoch of MJD 54628-58677 into seven distinct epochs, including the flat spectrum radio quasar (FSRQ) state, the transition state, and the BL Lac state. We obtained both a Fermi -LAT SED and a multi-wavelength SED for each of these distinct epochs. The source exhibits a transformation from a quiescent state to a highly active state, as evidenced by the variability of the EW. The multi-wavelength SEDs display a prominent external Compton characteristic, even though the Fermi -LAT SED reveals both a FSRQ and a BL Lac state across the seven different epochs. To gain further insights, we employed a leptonic model that takes into account the soft photon fields originating from both synchrotron radiation and the external environment. By simulating the multi-wavelength SEDs for each epoch, we uncover the following results. Firstly, the energy density of the external photon fields evolves in an oscillatory manner over the seven different epochs. Also, the energy density of the external photon fields in the BL Lac state is lower than that in the FSRQ state. These findings suggest that the CL blazar represents a unique phase in the blazar sequence. Considering that the energy density of the external photon fields is proportional to the accretion rate, we propose that evidence for the interconversion of advection-dominated accretion flow (ADAF) discs and standard Shakura-Sunyaev discs (SSDs), --- as variations in accretion modes in the CL blazar --- can be obtained through observations by Fermi -LAT.