Receptor Ligands Research Articles

Lysosome-Targeting Bacterial Outer Membrane Vesicles for Tumor Specific Degradation of PD-L1.

Increased expression of immune check point genes, such as PD-L1, is one of the main reasons for immunosuppression, especially for colon cancer. Development of novel therapeutic strategies is of great importance to improve the prognosis. In this study, outer membrane vesicles (OMV) derived from Gram-negative bacteria are engineered to immune checkpoint blockade nanosystem for efficient elicitation of anti-tumor immunity. Briefly, the OMVs are engineered with Lyp1-Traptavidin (S52G, R53D mutant of streptavidin) fusion protein displayed on the surface. The Lyp-1 endows the OMV with the capacity to target tumor tissues, while the Traptavidin ensures easy decoration of biotinylated anti-PD-L1 and biotinylated M6P (mannose 6-phosphate). The simultaneously anchored anti-PD-L1 and M6P (ligand for cation-independent mannose 6-phosphate receptor) on the engineered OMVs coordinately direct the membrane PD-L1 to lysosome for degradation, and thus unleash the anti-tumor immunity. With syngeneic tumor model, the engineered OMVs are confirmed to boost immunity, inhibit cancer growth, and thus prolong survival. Together, A proposed OMV-based modular nanosystem that enables assembly of biotinylated anti-PD-L1 and M6P on the surface for tumor-targeted immune checkpoint blockade.

Structural insights into somatostatin receptor 5 bound with cyclic peptides.

Somatostatin receptor5 (SSTR5) is highly expressed in ACTH-secreting pituitary adenomas and is an important drug target for the treatment of Cushing's disease. Two cyclic SST analog peptides (pasireotide and octreotide) both can activate SSTR5 and SSTR2. Pasireotide is preferential binding to SSTR5 than octreotide, while octreotide is biased to SSTR2 than SSTR5. The lack of selectivity of both pasireotide and octreotide causes side effects, such as hyperglycemia, gastrointestinal disturbance, and abnormal glucose homeostasis. However, little is known about the binding and selectivity mechanisms of pasireotide and octreotide with SSTR5, limiting the development of subtype-selective SST analog drugs specifically targeting SSTR5. Here, we report two cryo-electron microscopy (cryo-EM) structures of SSTR5-Gi complexes activated by pasireotide and octreoitde at resolutions of 3.09 Å and 3.24 Å, respectively. In combination with structural analysis and functional experiments, our results reveal the molecular mechanisms of ligand recognition and receptor activation. We also demonstrate that pasireotide preferentially binds to SSTR5 through the interactions between Tyr(Bzl)/DTrp of pasireotide and SSTR5. Moreover, we find that the Q2.63, N6.55, F7.35 and ECL2 of SSTR2 play a crucial role in octreotide biased binding of SSTR2. Our results will provide structural insights and offer new opportunities for the drug discovery of better selective pharmaceuticals targeting specific SSTR subtypes.

Development of a genetically encoded sensor for probing endogenous nociceptin opioid peptide release

Nociceptin/orphanin-FQ (N/OFQ) is a recently appreciated critical opioid peptide with key regulatory functions in several central behavioral processes including motivation, stress, feeding, and sleep. The functional relevance of N/OFQ action in the mammalian brain remains unclear due to a lack of high-resolution approaches to detect this neuropeptide with appropriate spatial and temporal resolution. Here we develop and characterize NOPLight, a genetically encoded sensor that sensitively reports changes in endogenous N/OFQ release. We characterized the affinity, pharmacological profile, spectral properties, kinetics, ligand selectivity, and potential interaction with intracellular signal transducers of NOPLight in vitro. Its functionality was established in acute brain slices by exogeneous N/OFQ application and chemogenetic induction of endogenous N/OFQ release from PNOC neurons. In vivo studies with fibre photometry enabled direct recording of NOPLight binding to exogenous N/OFQ receptor ligands, as well as detection of endogenous N/OFQ release within the paranigral ventral tegmental area (pnVTA) during natural behaviors and chemogenetic activation of PNOC neurons. In summary, we show here that NOPLight can be used to detect N/OFQ opioid peptide signal dynamics in tissue and freely behaving animals.

Acute exercise activates the AHR in peripheral blood mononuclear cells in an intensity-dependent manner.

The kynurenine pathway (KP) of tryptophan degradation generates several metabolites such as kynurenine (KYN) or kynurenic acid (KA) that serve as endogenous ligands of the aryl hydrocarbon receptor (AHR). Due to its distinct biological roles particularly modulating the immune system, the AHR is a current therapeutic target across different inflammation-related diseases. Here, we show an acute exercise-induced increase in AHR ligand availability on a systemic level and a kynurenine pathway activation in peripheral blood mononuclear cells (PBMCs). Concurrently, the AHR is activated in PBMCs following acute exercise. Exercise effects on both, kynurenic acid and AHR activation in PBMCs were greater in response to high-intensity interval exercise (HIIE) (50 min, six 3-min intervals at 90% V̇o2peak, and 3-min intervals at 50% V̇o2peak in between) compared with workload-matched moderate-intensity continuous exercise (MICE) (50 min). In conclusion, these data indicate a novel mechanistic link in how exercise modulates the immune system through the kynurenine pathway-AHR axis, potentially underlying exercise-induced benefits in various chronic diseases.NEW & NOTEWORTHY The findings of this study show that acute endurance exercise activates a receptor that has been described to integrate metabolic signals into the immune system. We uncover a potential mechanistic link on how exercise modulates the immune system through the kynurenine pathway-AHR axis, potentially underlying exercise-induced benefits in various chronic diseases and of relevance for other cell types.

Development of FluoAHRL: A Novel Synthetic Fluorescent Compound That Activates AHR and Potentiates Anti-Inflammatory T Regulatory Cells.

Aryl Hydrocarbon Receptor (AHR) ligands, upon binding, induce distinct gene expression profiles orchestrated by the AHR, leading to a spectrum of pro- or anti-inflammatory effects. In this study, we designed, synthesized and evaluated three indole-containing potential AHR ligands (FluoAHRL: AGT-4, AGT-5 and AGT-6). All synthesized compounds were shown to emit fluorescence in the near-infrared. Their AHR agonist activity was first predicted using in silico docking studies, and then confirmed using AHR luciferase reporter cell lines. FluoAHRLs were tested in vitro using mouse peritoneal macrophages and T lymphocytes to assess their immunomodulatory properties. We then focused on AGT-5, as it illustrated the predominant anti-inflammatory effects. Notably, AGT-5 demonstrated the ability to foster anti-inflammatory regulatory T cells (Treg) while suppressing pro-inflammatory T helper (Th)17 cells in vitro. AGT-5 actively induced Treg differentiation from naïve CD4+ cells, and promoted Treg proliferation, cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) expression and interleukin-10 (IL-10) production. The increase in IL-10 correlated with an upregulation of Signal Transducer and Activator of Transcription 3 (STAT3) expression. Importantly, the Treg-inducing effect of AGT-5 was also observed in human tonsil cells in vitro. AGT-5 showed no toxicity when applied to zebrafish embryos and was therefore considered safe for animal studies. Following oral administration to C57BL/6 mice, AGT-5 significantly upregulated Treg while downregulating pro-inflammatory Th1 cells in the mesenteric lymph nodes. Due to its fluorescent properties, AGT-5 could be visualized both in vitro (during uptake by macrophages) and ex vivo (within the lamina propria of the small intestine). These findings make AGT-5 a promising candidate for further exploration in the treatment of inflammatory and autoimmune diseases.

Functional Integration of Synthetic Cells into 3D Microfluidic Devices for Artificial Organ-On-Chip Technologies.

Microfluidics plays a pivotal role in organ-on-chip technologies and in the study of synthetic cells, especially in the development and analysis of artificial cell models. However, approaches that use synthetic cells as integral functional components for microfluidic systems to shape the microenvironment of natural living cells cultured on-chip are not explored. Here, colloidosome-based synthetic cells are integrated into 3D microfluidic devices, pioneering the concept of synthetic cell-based microenvironments for organs-on-chip. Methods are devised to create dense and stable networks of silica colloidosomes, enveloped by supported lipid bilayers, within microfluidic channels. These networks promote receptor-ligand interactions with on-chip cultured cells. Furthermore, a technique is introduced for the controlled release of growth factors from the synthetic cells into the channels, using a calcium alginate-based hydrogel formation within the colloidosomes. To demonstrate the potential of the technology, a modular plug-and-play lymph-node-on-a-chip prototype that guides the expansion of primary human T cells by stimulating receptor ligands on the T cells and modulating their cytokine environment is presented. This integration of synthetic cells into microfluidic systems offers a new direction for organ-on-chip technologies and suggests further avenues for exploration in potential therapeutic applications.

Joint EANM/EANO/RANO/SNMMI practice guideline/procedure standards for diagnostics and therapy (theranostics) of meningiomas using radiolabeled somatostatin receptor ligands: version 1.0.

To provide practice guideline/procedure standards for diagnostics and therapy (theranostics) of meningiomas using radiolabeled somatostatin receptor (SSTR) ligands. This joint practice guideline/procedure standard was collaboratively developed by the European Association of Nuclear Medicine (EANM), the Society of Nuclear Medicine and Molecular Imaging (SNMMI), the European Association of Neurooncology (EANO), and the PET task force of the Response Assessment in Neurooncology Working Group (PET/RANO). Positron emission tomography (PET) using somatostatin receptor (SSTR) ligands can detect meningioma tissue with high sensitivity and specificity and may provide clinically relevant information beyond that obtained from structural magnetic resonance imaging (MRI) or computed tomography (CT) imaging alone. SSTR-directed PET imaging can be particularly useful for differential diagnosis, delineation of meningioma extent, detection of osseous involvement, and the differentiation between posttherapeutic scar tissue and tumour recurrence. Moreover, SSTR-peptide receptor radionuclide therapy (PRRT) is an emerging investigational treatment approach for meningioma. These practice guidelines will define procedure standards for the application of PET imaging in patients with meningiomas and related SSTR-targeted PRRTs in routine practice and clinical trials and will help to harmonize data acquisition and interpretation across centers, facilitate comparability of studies, and to collect larger databases. The current document provides additional information to the evidence-based recommendations from the PET/RANO Working Group regarding the utilization of PET imaging in meningiomas Galldiks (Neuro Oncol. 2017;19(12):1576-87). The information provided should be considered in the context of local conditions and regulations.

DIPG-49. SPATIAL TRANSCRIPTOMIC SEQUENCING OF A DIPG PATIENT TUMOUR RESOURCE

Abstract BACKGROUND Diffuse Intrinsic Pontine Glioma (DIPG), the most common subtype of Diffuse Midline Glioma (DMG), is a brainstem high-grade glioma arising in young children and always proves fatal. Major challenges include the disease’s intratumoural genetic and cellular heterogeneity as well as its diffusely invasive phenotype. Research of the last few years has highlighted that interactions between cancer cells, the nervous system and immune cells crucially contribute to tumour cell invasion and disease malignancy. Hence, a better understanding of cancer-promoting interactions is a key requirement to elucidate novel strategies for the treatment of this devastating disease. METHOD We performed spatial transcriptomic sequencing on 10 sequential tumour-infiltrated DIPG patient brainstem regions, using the 10x Genomics Visium platform. RESULTS Spatially-informed analysis and cell type clustering overall highlighted the molecular intratumoural heterogeneity present in the disease. We assessed cell cluster interactions as well as receptor-ligand (RL) pairing, illustrating communication between neuronal, immune cell and tumour clusters. We further determined respective RL pairs involved in such. To address the question whether invasive edges genetically differ from the tumour core, we evaluated genes that are significantly correlated with distal brainstem regions compared to tumour proximal sites. Results revealed gene signatures that are highly associated with neuronal signalling and communication, validating previous findings emphasising the importance of neuron-to-glioma interactions driving DIPG disease progression. CONCLUSION DIPG is a lethal paediatric brainstem glioma for which more durable therapeutic modalities remain to be found. In-depth analysis of this disease is often hampered due to the lack of patient tissue suitable for laboratory studies. Our patient autopsy specimen, spanning the entire tumour-infiltrated brainstem provided a platform to study this aggressive disease in a spatio-temporal manner. This analysis elucidates how DIPG is driven by the tumour microenvironment, including associated receptor-ligand interactions. This has the potential to ultimately discover new treatment targets.

Natural killer cells in cancer immunotherapy.

Natural killer (NK) cells, as innate lymphocytes, possess cytotoxic capabilities and engage target cells through a repertoire of activating and inhibitory receptors. Particularly, natural killer group 2, member D (NKG2D) receptor on NK cells recognizes stress-induced ligands-the MHC class I chain-related molecules A and B (MICA/B) presented on tumor cells and is key to trigger the cytolytic response of NK cells. However, tumors have developed sophisticated strategies to evade NK cell surveillance, which lead to failure of tumor immunotherapy. In this paper, we summarized these immune escaping strategies, including the downregulation of ligands for activating receptors, upregulation of ligands for inhibitory receptors, secretion of immunosuppressive compounds, and the development of apoptosis resistance. Then, we focus on recent advancements in NK cell immune therapies, which include engaging activating NK cell receptors, upregulating NKG2D ligand MICA/B expression, blocking inhibitory NK cell receptors, adoptive NK cell therapy, chimeric antigen receptor (CAR)-engineered NK cells (CAR-NK), and NKG2D CAR-T cells, especially several vaccines targeting MICA/B. This review will inspire the research in NK cell biology in tumor and provide significant hope for improving cancer treatment outcomes by harnessing the potent cytotoxic activity of NK cells.

Porphyrin derivatives inhibit tumor necrosis factor α-induced gene expression and reduce the expression and increase the cross-linked forms of cellular components of the nuclear factor κB signaling pathway

The transcription factor nuclear factor κB (NF-κB) is activated by proinflammatory cytokines, such as tumor necrosis factor α (TNF-α) and Toll-like receptor (TLR) ligands. Screening of NPDepo chemical libraries identified porphyrin derivatives as anti-inflammatory compounds that strongly inhibited the up-regulation of intercellular adhesion molecule-1 (ICAM-1) expression induced by TNF-α, interleukin-1α, the TLR3 ligand, and TLR4 ligand in human umbilical vein endothelial cells. In the present study, the mechanisms of action of porphyrin derivatives were further elucidated using human lung adenocarcinoma A549 cells. Porphyrin derivatives, i.e., dimethyl-2,7,12,18-tetramethyl-3,8-di(1-methoxyethyl)-21H,23H-porphine-13,17-dipropionate (1) and pheophorbide a (2), inhibited TNF-α-induced ICAM-1 expression and decreased the TNF-α-induced transcription of ICAM-1, vascular cell adhesion molecule-1, and E-selectin genes. 1 and 2 reduced the expression of the NF-κB subunit RelA protein for 1 h, which was not rescued by the inhibition of proteasome- and lysosome-dependent protein degradation. In addition, 1 and 2 decreased the expression of multiple components of the TNF receptor 1 complex, and this was accompanied by the appearance of their cross-linked forms. As common components of the NF-κB signaling pathway, 1 and 2 also cross-linked the α, β, and γ subunits of the inhibitor of NF-κB kinase complex and the NF-κB subunits RelA and p50. Cellular protein synthesis was prevented by 2, but not by 1. Therefore, the present results indicate that porphyrin derivative 1 reduced the expression and increased the cross-linked forms of cellular components required for the NF-κB signaling pathway without affecting global protein synthesis.

Identification of lung adenocarcinoma subtypes based on mitochondrial energy metabolism-related genes

Background Identifying subtypes of lung adenocarcinoma (LUAD) patients based on mitochondrial energy metabolism and immunotherapy sensitivity is essential for precision cancer treatment. Methods LUAD subtypes were identified using unsupervised consensus clustering, and results were subjected to immune and tumor mutation analyses. DEGs between subtypes were identified by differential analysis. Functional enrichment and PPI network analyses were conducted. Patients were classified into high and low expression groups based on the expression of the top 10 hub genes, and survival analysis was performed. Drugs sensitive to feature genes were screened based on the correlation between hub gene expression and drug IC50 value. qRT-PCR and western blot were used for gene expression detection, and CCK-8 and flow cytometry were for cell viability and apoptosis analysis. Results Cluster-1 had significantly higher overall survival and a higher degree of immunoinfiltration and immunophenotypic score, but a lower TIDE score, DEPTH score, and TMB. Enrichment analysis showed that pathways and functions of DEGs between two clusters were mainly related to the interaction of receptor ligands with intracellular proteases. High expression of hub genes corresponded to lower patient survival rates. The predicted drugs with high sensitivity to feature genes were CDK1: Ribavirin (0.476), CCNB2: Hydroxyurea (0.474), Chelerythrine (0.470), and KIF11: Ribavirin (0.471). KIF11 and CCNB2 were highly expressed in LUAD cells and promoted cell viability and inhibited cell apoptosis. Conclusion This study identified two subtypes of LUAD, with cluster-1 being more suitable for immunotherapy. These results provided a reference for the development of precision immunotherapy for LUAD patients.

The effect of dietary sodium octanoate on Ghrelin concentration and feed intake in chickens and turkeys: a comparative study

Active ghrelin (AG) is produced through the post-translational addition of n-octanoic acid to the amino residue Ser-3, making it the natural ligand for the ghrelin receptor. The synthesis of AG is contingent upon specific dietary fatty acids as substrates for the acylation process. Prior studies have demonstrated that AG infusion can lead to reduced feed intake (FI) in broiler chickens, suggesting that manipulating AG may serve as an alternative to quantitative feed restriction in broiler breeders. In this study, we evaluated the effect of dietary sodium octanoate (Octanoate) on FI, water intake (WI), BW, total ghrelin, and β-hydroxybutyrate (BHB) concentration in two avian species. Broiler chickens and turkeys were reared as recommended by the industry. At 3 wk of age, birds were randomly assigned to a 2 × 3 factorial. The first factor included two species (chickens and turkeys), and the second included doses (0, 4, and 8 mg/mL) of Octanoate in drinking water for 30 d. Feed and WI were recorded daily, while body weight and blood samples were obtained weekly. In chickens, Octanoate doses increased ghrelin and BHB concentrations linearly, while FI and BW decreased linearly with rising Octanoate doses (P < 0.05). However, Octanoate doses did not affect ghrelin, BHB, FI, or BW in turkeys. In conclusion, our data indicate that sodium octanoate administration elicits a differential response in feed intake and body weight gain in chickens and turkeys.

Cytochrome P450 and UDP-Glucuronosyltransferase Expressions, Activities, and Induction Abilities in 3D-Cultured Human Renal Proximal Tubule Epithelial Cells.

The role of the kidney as an excretory organ for exogenous and endogenous compounds is well recognized, but there is a wealth of data demonstrating that the kidney has significant metabolizing capacity for a variety of exogenous and endogenous compounds that in some cases surpass the liver. The induction of drug-metabolizing enzymes by some chemicals can cause drug-drug interactions and intraindividual variability in drug clearance. In this study, we evaluated the expression and induction of cytochrome P450 (P450) and UDP-glucuronosyltransferase (UGT) isoforms in 3D-cultured primary human renal proximal tubule epithelial cells (RPTEC) to elucidate their utility as models of renal drug metabolism. CYP2B6, CYP2E1, CYP3A4, CYP3A5, and all detected UGTs (UGT1A1, UGT1A4, UGT1A6, UGT1A9, and UGT2B7) mRNA levels in 3D-RPTEC were significantly higher than those in 2D-RPTEC and HK-2 cells and were close to the levels in the human kidney cortex. CYP1B1 and CYP2J2 mRNA levels in 3D-RPTEC were comparable to those in 2D-RPTEC, HK-2 cells, and the human kidney cortex. Midazolam 1'-hydroxylation, trifluoperazine N-glucuronidation, serotonin O-glucuronidation, propofol O-glucuronidation, and morphine 3-glucuronidation in the 3D-RPTEC were significantly higher than the 2D-RPTEC and comparable to those in the HepaRG cells, although bupropion, ebastine, and calcitriol hydroxylations were not different between the 2D- and 3D-RPTEC. Treatment with ligands of the aryl hydrocarbon receptor and farnesoid X receptor induced CYP1A1 and UGT2B4 expression, respectively, in 3D-RPTEC compared with 2D-RPTEC. We provided information on the expression, activity, and induction abilities of P450s and UGTs in 3D-RPTEC as an in vitro human renal metabolism model. SIGNIFICANCE STATEMENT: This study demonstrated that the expression of cytochrome P450s (P450s) and UDP-glucuronosyltransferases (UGTs) in 3D-cultured primary human renal proximal tubule epithelial cells (3D-RPTEC) was higher than those in 2D-cultured primary human renal proximal tubule epithelial cells and HK-2 cells. The results were comparable to that in the human kidney cortex. 3D-RPTEC are useful for evaluating the induction of kidney P450s, UDP-glucuronosyltransferases, and human renal drug metabolism in cellulo.

Design, Synthesis, and Evaluation of a New Chemotype Fluorescent Ligand for the P2Y2 Receptor.

The P2Y2 receptor (P2Y2R) is a target for diseases including cancer, idiopathic pulmonary fibrosis, and atherosclerosis. However, there are insufficient P2Y2R antagonists available for validating P2Y2R function and future drug development. Evaluation of how (R)-5-(7-chloro-2-((2-ethoxyethyl)amino)-4H-benzo[5,6]cyclohepta[1,2-d]thiazol-4-yl)-1-methyl-4-thioxo-3,4-dihydropyrimidin-2(1H)-one, a previously published thiazole-based analogue of AR-C118925, binds in a P2Y2R homology model was used to design new P2Y2R antagonist scaffolds. One P2Y2R antagonist scaffold retained millimolar affinity for the P2Y2R and upon further functionalization with terminal carboxylic acid groups affinity was improved over 100-fold. This functionalized P2Y2R antagonist scaffold was employed to develop new chemotype P2Y2R fluorescent ligands, that were attainable in a convergent five-step synthesis. One of these fluorescent ligands demonstrated micromolar affinity (pK d = 6.02 ± 0.12, n = 5) for the P2Y2R in isolated cell membranes and distinct pharmacology from an existing P2Y2R fluorescent antagonist, suggesting it may occupy a different binding site on the P2Y2R.

Comparative transcriptome analysis reveals molecular damage associated with cryopreservation in Crassostrea angulata D-larvae rather than to cryoprotectant exposure

BackgroundThe Portuguese oyster Crassostrea angulata, a bivalve of significant economic and ecological importance, has faced a decline in both production and natural populations due to pathologies, climate change, and anthropogenic factors. To safeguard its genetic diversity and improve reproductive management, cryopreservation emerges as a valuable strategy. However, the cryopreservation methodologies lead to some damage in structures and functions of the cells and tissues that can affect post-thaw quality. Transcriptomics may help to understand the molecular consequences related to cryopreservation steps and therefore to identify different freezability biomarkers. This study investigates the molecular damage induced by cryopreservation in C. angulata D-larvae, focusing on two critical steps: exposure to cryoprotectant solution and the freezing/thawing process.ResultsExpression analysis revealed 3 differentially expressed genes between larvae exposed to cryoprotectant solution and fresh larvae and 611 differentially expressed genes in cryopreserved larvae against fresh larvae. The most significantly enriched gene ontology terms were “carbohydrate metabolic process”, “integral component of membrane” and “chitin binding” for biological processes, cellular components and molecular functions, respectively. Kyoto Encyclopedia of Genes and Genomes enrichment analysis identified the “neuroactive ligand receptor interaction”, “endocytosis” and “spliceosome” as the most enriched pathways. RNA sequencing results were validate by quantitative RT-PCR, once both techniques presented the same gene expression tendency and a group of 11 genes were considered important molecular biomarkers to be used in further studies for the evaluation of cryodamage.ConclusionsThe current work provided valuable insights into the molecular repercussions of cryopreservation on D-larvae of Crassostrea angulata, revealing that the freezing process had a more pronounced impact on larval quality compared to any potential cryoprotectant-induced toxicity. Additionally, was identify 11 genes serving as biomarkers of freezability for D-larvae quality assessment. This research contributes to the development of more effective cryopreservation protocols and detection methods for cryodamage in this species.

Transcriptomics of pectoralis major muscles uncovers a footprint of enriched pathways in five diverse backyard chicken breeds of India

Genetic diversity existing between the chicken breeds can be used as a means to unravel the biological mechanisms affecting traits of commercial prominence. The present study attempted to compare the biological pathways enriched in pectoralis major muscles in five diverse chicken breeds. RNA sequencing data was generated from four biological replicates of pectoralis major muscles from Ankleshwar, Aseel, Kadaknath, Punjab Brown and Nicobari chicken. A total of 40 genes each for Nicobari and Aseel, 46 for Punjab Brown, 65 for Kadaknath and 86 for Ankaleshwar were found to be unique. The Neuroactive ligand-receptor interaction pathway was enriched in Ankaleshwar, Aseel and Kadaknath. However, the set of genes identified in this pathway were associated with different ligand receptors in each of the three breeds. The Wnt signaling pathway showed significant enrichment in Nicobari chicken while the Steroid biosynthesis pathway showed prominent expression in Punjab Brown chicken. The significant pathways pinpoint to genetic characteristics associated with each breed suggesting a transcriptome footprint. Our study is a first step toward determining the genetic basis of phenotypic diversity in chicken.

The interferon-rich skin environment regulates Langerhans cell ADAM17 to promote photosensitivity in lupus.

The autoimmune disease lupus erythematosus (lupus) is characterized by photosensitivity, where even ambient ultraviolet radiation (UVR) exposure can lead to development of inflammatory skin lesions. We have previously shown that Langerhans cells (LCs) limit keratinocyte apoptosis and photosensitivity via a disintegrin and metalloprotease 17 (ADAM17)-mediated release of epidermal growth factor receptor (EGFR) ligands and that LC ADAM17 sheddase activity is reduced in lupus. Here, we sought to understand how the lupus skin environment contributes to LC ADAM17 dysfunction and, in the process, differentiate between effects on LC ADAM17 sheddase function, LC ADAM17 expression, and LC numbers. We show through transcriptomic analysis a shared IFN-rich environment in non-lesional skin across human lupus and three murine models: MRL/lpr, B6.Sle1yaa, and imiquimod (IMQ) mice. IFN-I inhibits LC ADAM17 sheddase activity in murine and human LCs, and IFNAR blockade in lupus model mice restores LC ADAM17 sheddase activity, all without consistent effects on LC ADAM17 protein expression or LC numbers. Anti-IFNAR-mediated LC ADAM17 sheddase function restoration is associated with reduced photosensitive responses that are dependent on EGFR signaling and LC ADAM17. Reactive oxygen species (ROS) is a known mediator of ADAM17 activity; we show that UVR-induced LC ROS production is reduced in lupus model mice, restored by anti-IFNAR, and is cytoplasmic in origin. Our findings suggest that IFN-I promotes photosensitivity at least in part by inhibiting UVR-induced LC ADAM17 sheddase function and raise the possibility that anifrolumab ameliorates lupus skin disease in part by restoring this function. This work provides insight into IFN-I-mediated disease mechanisms, LC regulation, and a potential mechanism of action for anifrolumab in lupus.

Covalent and Visible‐Light Photoswitchable Derivatives of the Potent Synthetic Opioid Isotonitazene and Other Nitazenes

AbstractIsotonitazene belongs to a potent class of μ‐opioid receptor (μOR) ligands, known as nitazenes. The lack of knowledge surrounding this agonist and others in its class has sparked thorough re‐investigations. To aid in these investigations, the purportedly covalent yet underexplored nitazene BIT was biochemically re‐evaluated in this work, along with a newly synthesized analogue, Iso‐BIT. Moreover, in the pursuit of understanding the mechanism, function and interactions of the μOR, this study involved developing photoswitchable nitazene derivatives as potential probe molecules. Converting known ligands into azo‐containing photoswitchable derivatives offers the opportunity to modulate ligand structure with light, allowing for photocontrol of compound activity. While photocontrol of μOR activity could not be entirely achieved, photophysical evaluation of these 2‐benzimidazole azo‐arenes revealed a novel photoswitch scaffold that responds to visible light. Furthermore, azo‐containing 2 e and 3 e emerged as promising nitazene derivatives that were able to form an exceptionally high fraction of covalent‐ligand receptor complexes with wild‐type μOR at physiological pH.

Self-Assembled PD-L1 Downregulator to Boost Photodynamic Activated Tumor Immunotherapy Through CDK5 Inhibition.

The immunosuppressive characteristics and acquired immune resistance can restrain the therapy-initiated anti-tumor immunity. In this work, an antibody free programmed death receptor ligand 1 (PD-L1) downregulator (designated as CeSe) is fabricated to boost photodynamic activated immunotherapy through cyclin-dependent kinase 5 (CDK5) inhibition. Among which, FDA approved photosensitizer of chlorin e6 (Ce6) and preclinical available CDK5 inhibitor of seliciclib (Se) are utilized to prepare the nanomedicine of CeSe through self-assembly technique without drug excipient. Nanoscale CeSe exhibits an increased stability and drug delivery efficiency, contributing to intracellular production of reactive oxygen species (ROS) for robust photodynamic therapy (PDT). The PDT of CeSe can not only suppress the primary tumor growth, but also induce the immunogenic cell death (ICD) to release tumor associated antigens. More importantly, the CDK5 inhibition by CeSe can downregulate PD-L1 to re-activate the systemic anti-tumor immunity by decreasing the tumor immune escape and therapy-induced acquired immune resistance. This work provides an antibody free strategy to activate systemic immune response for metastatic tumor treatment, which may accelerate the development of translational nanomedicine with sophisticated mechanism.

Vertical Transfer of Maternal Gut Microbes to Offspring of Western Diet-Fed Dams Drives Reduced Levels of Tryptophan Metabolites and Postnatal Innate Immune Response.

Maternal obesity and/or Western diet (WD) is associated with an increased risk of metabolic dysfunction-associated steatotic liver disease (MASLD) in offspring, driven, in part, by the dysregulation of the early life microbiome. Here, using a mouse model of WD-induced maternal obesity, we demonstrate that exposure to a disordered microbiome from WD-fed dams suppressed circulating levels of endogenous ligands of the aryl hydrocarbon receptor (AHR; indole, indole-3-acetate) and TMAO (a product of AHR-mediated transcription), as well as hepatic expression of Il10 (an AHR target), in offspring at 3 weeks of age. This signature was recapitulated by fecal microbial transfer from WD-fed pregnant dams to chow-fed germ-free (GF) lactating dams following parturition and was associated with a reduced abundance of Lactobacillus in GF offspring. Further, the expression of Il10 was downregulated in liver myeloid cells and in LPS-stimulated bone marrow-derived macrophages (BMDM) in adult offspring, suggestive of a hypo-responsive, or tolerant, innate immune response. BMDMs from adult mice lacking AHR in macrophages exhibited a similar tolerogenic response, including diminished expression of Il10. Overall, our study shows that exposure to maternal WD alters microbial metabolites in the offspring that affect AHR signaling, potentially contributing to innate immune hypo-responsiveness and progression of MASLD, highlighting the impact of early life gut dysbiosis on offspring metabolism. Further investigations are warranted to elucidate the complex interplay between maternal diet, gut microbial function, and the development of neonatal innate immune tolerance and potential therapeutic interventions targeting these pathways.