Transcriptomes of aging brain, heart, muscle, and spleen from female and male African turquoise killifish.

The African turquoise killifish is an emerging vertebrate model organism with great potential for aging research due to its naturally short lifespan. Thus far, turquoise killifish aging 'omic' studies have examined a single organ, single sex and/or evaluated samples from non-reference strains. Here, we describe a resource dataset of ribosomal RNA-depleted RNA-seq libraries generated from the brain, heart, muscle, and spleen from both sexes, as well as young and old animals, in the reference GRZ turquoise killifish strain. We provide basic quality control steps and demonstrate the utility of our dataset by performing differential gene expression and gene ontology analyses by age and sex. Importantly, we show that age has a greater impact than sex on transcriptional landscapes across probed tissues. Finally, we confirm transcription of transposable elements (TEs), which are highly abundant and increase in expression with age in brain tissue. This dataset will be a useful resource for exploring gene and TE expression as a function of both age and sex in a powerful naturally short-lived vertebrate model.

Widespread sex dimorphism across single-cell transcriptomes of adult African turquoise killifish tissues.

The African turquoise killifish (Nothobranchius furzeri), the shortest-lived vertebrate that can be bred in captivity, is an emerging model organism for aging research. Here, we describe a multitissue, single-cell gene expression atlas of female and male blood, kidney, liver, and spleen. We annotate 22 cell types, define marker genes, and infer differentiation trajectories. We find pervasive sex-dimorphic gene expression across cell types. Sex-dimorphic genes tend to be linked to lipid metabolism, consistent with clear differences in lipid storage in female vs. male turquoise killifish livers. We use machine learning to predict sex using single-cell gene expression and identify potential markers for molecular sex identity. As a proof of principle, we show that our atlas can be used to deconvolute existing bulk RNA sequencing (RNA-seq) data to obtain accurate estimates of cell type proportions. This atlas can be a resource to the community that could be leveraged to develop cell-type-specific expression in transgenic animals.

Participant Experience with Protocol Research Kidney Biopsies in the Kidney Precision Medicine Project.

BACKGROUND: Kidney biopsies are procedures commonly performed in clinical nephrology and are increasingly used in research. In this study we aimed to evaluate the experiences of participants who underwent research kidney biopsies in the Kidney Precision Medicine Project (KPMP). METHODS: KPMP research participants with acute kidney injury (AKI) or chronic kidney disease (CKD) were enrolled at nine recruitment sites in the United States between September 2019 to January 2023. At 28 days post-biopsy, participants were invited to complete a survey to share their experiences, including: motivation to participate in research; comprehension of informed consent; pain and anxiety during and after the biopsy procedure; overall satisfaction with KPMP participation; and impact of the study on their lives. The survey was developed in collaboration with the KPMP Community Engagement Committee and the Institute of Translational Health Sciences at the University of Washington. RESULTS: 111 participants completed the survey, 23 enrolled for AKI and 88 for CKD. Median age was 61 (IQR 48-67) years, 43% were women, 28% were Black, and 18% were of Hispanic ethnicity. Survey respondents most commonly joined KPMP to help future patients (59%). The consent form was understood by 99% and 97% recognized their important role in the study. Pain during the biopsy was reported by 50%, at a median level of 1 (IQR 0-3) on a 0-10 scale. Anxiety during the biopsy was described by 64% at a median level of 3 (IQR 1-5) on a 0-10 scale. More than half conveyed that KPMP participation impacted their diet, physical activity, and how they think about kidney disease. CONCLUSIONS: KPMP survey respondents were most commonly motivated to participate in research protocol kidney biopsies by altruism, with excellent understanding of the informed consent process.

Discovery of IACS-52825, a Potent and Selective DLK Inhibitor for Treatment of Chemotherapy-Induced Peripheral Neuropathy.

Chemotherapy-induced peripheral neuropathy (CIPN) is a major unmet medical need with limited treatment options. Despite different mechanisms of action, diverse chemotherapeutics can cause CIPN through a converged pathway─an active axon degeneration program that engages the dual leucine zipper kinase (DLK). DLK is a neuronally enriched kinase upstream in the MAPK-JNK cascade, and while it is dormant under physiological conditions, DLK mediates a core mechanism for neuronal injury response under stress conditions, making it an attractive target for treatment of neuronal injury and neurodegenerative diseases. We have developed potent, selective, brain penetrant DLK inhibitors with excellent PK and activity in mouse models of CIPN. Lead compound IACS-52825 (22) showed strongly effective reversal of mechanical allodynia in a mouse model of CIPN and was advanced into preclinical development.

Widespread sex-dimorphism across single-cell transcriptomes of adult African turquoise killifish tissues.

The African turquoise killifish (Nothobranchius furzeri), the shortest-lived vertebrate that can be bred in captivity, is an emerging model organism to study vertebrate aging. Here we describe the first multi-tissue, single-cell gene expression atlas of female and male turquoise killifish tissues comprising immune and metabolic cells from the blood, kidney, liver, and spleen. We were able to annotate 22 distinct cell types, define associated marker genes, and infer differentiation trajectories. Using this dataset, we found pervasive sex-dimorphic gene expression across cell types, especially in the liver. Sex-dimorphic genes tended to be involved in processes related to lipid metabolism, and indeed, we observed clear differences in lipid storage in female vs. male turquoise killifish livers. Importantly, we use machine-learning to predict sex using single-cell gene expression in our atlas and identify potential transcriptional markers for molecular sex identity in this species. As proof-of-principle, we show that our atlas can be used to deconvolute existing liver bulk RNA-seq data in this species to obtain accurate estimates of cell type proportions across biological conditions. We believe that this single-cell atlas can be a resource to the community that could notably be leveraged to identify cell type-specific genes for cell type-specific expression in transgenic animals.

Dynamic regulation of gonadal transposon control across the lifespan of the naturally short-lived African turquoise killifish.

Although germline cells are considered to be functionally "immortal," both the germline and supporting somatic cells in the gonad within an organism experience aging. With increased age at parenthood, the age-related decline in reproductive success has become an important biological issue for an aging population. However, molecular mechanisms underlying reproductive aging across sexes in vertebrates remain poorly understood. To decipher molecular drivers of vertebrate gonadal aging across sexes, we perform longitudinal characterization of the gonadal transcriptome throughout the lifespan in the naturally short-lived African turquoise killifish (Nothobranchius furzeri). By combining mRNA-seq and small RNA-seq from 26 individuals, we characterize the aging gonads of young-adult, middle-aged, and old female and male fish. We analyze changes in transcriptional patterns of genes, transposable elements (TEs), and piRNAs. We find that testes seem to undergo only marginal changes during aging. In contrast, in middle-aged ovaries, the time point associated with peak female fertility in this strain, PIWI pathway components are transiently down-regulated, TE transcription is elevated, and piRNA levels generally decrease, suggesting that egg quality may already be declining at middle-age. Furthermore, we show that piRNA ping-pong biogenesis declines steadily with age in ovaries, whereas it is maintained in aging testes. To our knowledge, this data set represents the most comprehensive transcriptomic data set for vertebrate gonadal aging. This resource also highlights important pathways that are regulated during reproductive aging in either ovaries or testes, which could ultimately be leveraged to help restore aspects of youthful reproductive function.

Discovery of an agonistic Siglec-6 antibody that inhibits and reduces human mast cells.

Mast cells (MC) are key drivers of allergic and inflammatory diseases. Sialic acid-binding immunoglobulin-like lectin (Siglec)-6 is an immunoregulatory receptor found on MCs. While it is recognized that engaging Siglecs with antibodies mediates inhibition across immune cells, the mechanisms that govern this agonism are not understood. Here we generated Siglec-6 mAb clones (AK01 to AK18) to better understand Siglec-6-mediated agonism. Siglec-6 mAbs displayed epitope-dependent receptor internalization and inhibitory activity. We identified a Siglec-6 mAb (AK04) that required Fc-mediated interaction for receptor internalization and induced inhibition and antibody-dependent cellular phagocytosis against MCs. AK04-mediated MC inhibition required Siglec-6 immunoreceptor tyrosine-based inhibitory motif (ITIM) and ITIM-like domains and was associated with receptor cluster formation containing inhibitory phosphatases. Treatment of humanized mice with AK04 inhibited systemic anaphylaxis with a single dose and reduced MCs with chronic dosing. Our findings suggest Siglec-6 activity is epitope dependent and highlight an agonistic Siglec-6 mAb as a potential therapeutic approach in allergic disease.

Macrophage targeted triptolide micelles capable of cGAS-STING pathway inhibition for rheumatoid arthritis treatment.

The abundant M1 macrophages in the joint synovium were the main factors that exacerbate rheumatoid arthritis (RA) by secreting various types of inflammatory cytokines. Here, we note that cGAS-STING, an important pro-inflammatory pathway, was significantly up-regulated in RA, enabling it be the potential target for RA therapy. Therefore, in this work, we developed M1 macrophages targeted micelles capable of cGAS-STING pathway inhibition for the smart treatment of RA. The folic acid (FA) and lauric acid (LA) were modified on dextran to obtain an amphiphilic polymer (FDL). Then, FDL was subsequently applied to encapsulate triptolide (TP) to form FDL@TP nanomicelles. The FDL@TP could target the joint and enhance the cell uptake of TP by M1 macrophages (overexpressing folate receptor-ß), which also reduced the side effects of TP on normal tissues. In M1 macrophages, the released TP, acted as an anti-inflammatory and immunosuppressant, obviously down-regulated the expressions of cGAS and STING protein, and thus reduced the secretion of TNF-α, IL-1ß and IL-6. Importantly, compared with the same dose of free TP, FDL@TP could significantly enhance the anti-inflammatory effect. Therefore, FDL@TP nanomicelles were believed to be superior candidates for the clinical treatment of RA.

Functional and Phenotypic Characterization of Siglec-6 on Human Mast Cells.

Mast cells are tissue-resident cells that contribute to allergic diseases, among others, due to excessive or inappropriate cellular activation and degranulation. Therapeutic approaches to modulate mast cell activation are urgently needed. Siglec-6 is an immunoreceptor tyrosine-based inhibitory motif (ITIM)-bearing receptor selectively expressed by mast cells, making it a promising target for therapeutic intervention. However, the effects of its engagement on mast cells are poorly defined. Siglec-6 expression and endocytosis on primary human mast cells and mast cell lines were assessed by flow cytometry. SIGLEC6 mRNA expression was examined by single-cell RNAseq in esophageal tissue biopsy samples. The ability of Siglec-6 engagement or co-engagement to prevent primary mast cell activation was determined based on assessments of mediator and cytokine secretion and degranulation markers. Siglec-6 was highly expressed by all mast cells examined, and the SIGLEC6 transcript was restricted to mast cells in esophageal biopsy samples. Siglec-6 endocytosis occurred with delayed kinetics relative to the related receptor Siglec-8. Co-crosslinking of Siglec-6 with FcεRIα enhanced the inhibition of mast cell activation and diminished downstream ERK1/2 and p38 phosphorylation. The selective, stable expression and potent inhibitory capacity of Siglec-6 on human mast cells are favorable for its use as a therapeutic target in mast cell-driven diseases.

The Inhibitory Receptor Siglec-8 Interacts With FcεRI and Globally Inhibits Intracellular Signaling in Primary Mast Cells Upon Activation.

Immunomodulation of mast cell (MC) activity is warranted in allergic and inflammatory diseases where MCs have a central role in pathogenesis. Targeting Siglec-8, an inhibitory receptor on MCs and eosinophils, has shown promising activity in preclinical and clinical studies. While the intracellular pathways that regulate Siglec-8 activity in eosinophils have been well studied, the signaling mechanisms that lead to MC inhibition have not been fully elucidated. Here, we evaluate the intracellular signaling pathways of Siglec-8-mediated inhibition in primary MCs using an anti-Siglec-8 monoclonal antibody (mAb). Phospho-proteomic profiling of FcεRI-activated MCs revealed Siglec-8 mAb-treatment globally inhibited proximal and downstream kinases, leading to attenuated MC activation and degranulation. In fact, Siglec-8 was found to directly interact with FcεRI signaling molecules. Siglec-8 inhibition was dependent on both cytoplasmic immunoreceptor tyrosine-based inhibitory motifs (ITIMs) that interact with the SH2 containing protein phosphatase Shp-2 upon Siglec-8 phosphorylation. Taken together, these data support a model in which Siglec-8 regulates proximal FcεRI-induced phosphorylation events through phosphatase recruitment and interaction with FcεRIγ, resulting in global inhibition of MCs upon Siglec-8 mAb engagement.

Discovery of IACS-9779 and IACS-70465 as Potent Inhibitors Targeting Indoleamine 2,3-Dioxygenase 1 (IDO1) Apoenzyme.

Indoleamine 2,3-dioxygenase 1 (IDO1), a heme-containing enzyme that mediates the rate-limiting step in the metabolism of l-tryptophan to kynurenine, has been widely explored as a potential immunotherapeutic target in oncology. We developed a class of inhibitors with a conformationally constrained bicyclo[3.1.0]hexane core. These potently inhibited IDO1 in a cellular context by binding to the apoenzyme, as elucidated by biochemical characterization and X-ray crystallography. A SKOV3 tumor model was instrumental in differentiating compounds, leading to the identification of IACS-9779 (62) and IACS-70465 (71). IACS-70465 has excellent cellular potency, a robust pharmacodynamic response, and in a human whole blood assay was more potent than linrodostat (BMS-986205). IACS-9779 with a predicted human efficacious once daily dose below 1 mg/kg to sustain >90% inhibition of IDO1 displayed an acceptable safety margin in rodent toxicology and dog cardiovascular studies to support advancement into preclinical safety evaluation for human development.

Pulmonary AL amyloidosis and multiple myeloma presenting as cough with diffuse pulmonary opacities.

Amyloidosis is an uncommon multisystem disease that can affect many organs. However, interstitial lung involvement is very rare. A 68-year-old man presented with long-standing dyspnoea and productive cough. After extensive investigation, including two non-diagnostic bronchoscopies, a surgical lung biopsy demonstrated pulmonary amyloidosis. A bone marrow biopsy confirmed multiple myeloma. The patient was treated with chemotherapy and an autologous stem cell transplant.

Health-related quality of life and work impairment in idiopathic inflammatory myopathies in South Australia.

AIM: The idiopathic inflammatory myopathies (IIM) are rare autoimmune diseases that are usually chronic and often present with skeletal muscle inflammation and weakness. We sought to examine the impact of IIM in a cohort of 50 South Australian patients on health-related quality of life (HRQOL) and work productivity (WP). We uniquely categorized patients across gender, IIM subtypes, employment status, and also whether there was extramuscular involvement from IIM. METHODS: Multiple modalities were used, as recommended by the International Myositis Assessment and Clinical Studies Group (IMACS), to assess the impact of IIM, including manual muscle strength testing (MMT-8), the Physician and Patient Global Activity Assessments (PHGAA, PTGAA), Myositis Disease Activity Assessment Tool (MDAAT), and serum creatinine kinase (CK) levels. The impacts of IIM on HRQOL and WP were analyzed using the Medical Outcomes Study 36-items Short Form (SF-36) and Work Productivity and Activity Impairment (WPAI) questionnaires, respectively. RESULTS: We found significantly lower HRQOL outcome scores in most of the SF-36 domains when compared to the most recent population norms (P ≤ .01). Physical health was predominantly affected with relative preservation of emotional health. There were also significant associations between MMT-8, PHGAA and PTGAA scores and HRQOL and WP. CONCLUSIONS: Our findings highlight the significant impact of IIM on HRQOL and WP in a well-characterized cohort of patients with IIM within Australia, and therefore the importance of a holistic approach to the management of these patients.

Mast Cell and Eosinophil Activation Are Associated With COVID-19 and TLR-Mediated Viral Inflammation: Implications for an Anti-Siglec-8 Antibody.

Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 infection represents a global health crisis. Immune cell activation via pattern recognition receptors has been implicated as a driver of the hyperinflammatory response seen in COVID-19. However, our understanding of the specific immune responses to SARS-CoV-2 remains limited. Mast cells (MCs) and eosinophils are innate immune cells that play pathogenic roles in many inflammatory responses. Here we report MC-derived proteases and eosinophil-associated mediators are elevated in COVID-19 patient sera and lung tissues. Stimulation of viral-sensing toll-like receptors in vitro and administration of synthetic viral RNA in vivo induced features of hyperinflammation, including cytokine elevation, immune cell airway infiltration, and MC-protease production-effects suppressed by an anti-Siglec-8 monoclonal antibody which selectively inhibits MCs and depletes eosinophils. Similarly, anti-Siglec-8 treatment reduced disease severity and airway inflammation in a respiratory viral infection model. These results suggest that MC and eosinophil activation are associated with COVID-19 inflammation and anti-Siglec-8 antibodies are a potential therapeutic approach for attenuating excessive inflammation during viral infections.

A monoclonal antibody to Siglec-8 suppresses non-allergic airway inflammation and inhibits IgE-independent mast cell activation.

In addition to their well characterized role in mediating IgE-dependent allergic diseases, aberrant accumulation and activation of mast cells (MCs) is associated with many non-allergic inflammatory diseases, whereby their activation is likely triggered by non-IgE stimuli (e.g., IL-33). Siglec-8 is an inhibitory receptor expressed on MCs and eosinophils that has been shown to inhibit IgE-mediated MC responses and reduce allergic inflammation upon ligation with a monoclonal antibody (mAb). Herein, we evaluated the effects of an anti-Siglec-8 mAb (anti-S8) in non-allergic disease models of experimental cigarette-smoke-induced chronic obstructive pulmonary disease and bleomycin-induced lung injury in Siglec-8 transgenic mice. Therapeutic treatment with anti-S8 inhibited MC activation and reduced recruitment of immune cells, airway inflammation, and lung fibrosis. Similarly, using a model of MC-dependent, IL-33-induced inflammation, anti-S8 treatment suppressed neutrophil influx, and cytokine production through MC inhibition. Transcriptomic profiling of MCs further demonstrated anti-S8-mediated downregulation of MC signaling pathways induced by IL-33, including TNF signaling via NF-κB. Collectively, these findings demonstrate that ligating Siglec-8 with an antibody reduces non-allergic inflammation and inhibits IgE-independent MC activation, supporting the evaluation of an anti-Siglec-8 mAb as a therapeutic approach in both allergic and non-allergic inflammatory diseases in which MCs play a role.

Discovery of IPN60090, a Clinical Stage Selective Glutaminase-1 (GLS-1) Inhibitor with Excellent Pharmacokinetic and Physicochemical Properties.

Inhibition of glutaminase-1 (GLS-1) hampers the proliferation of tumor cells reliant on glutamine. Known glutaminase inhibitors have potential limitations, and in vivo exposures are potentially limited due to poor physicochemical properties. We initiated a GLS-1 inhibitor discovery program focused on optimizing physicochemical and pharmacokinetic properties, and have developed a new selective inhibitor, compound 27 (IPN60090), which is currently in phase 1 clinical trials. Compound 27 attains high oral exposures in preclinical species, with strong in vivo target engagement, and should robustly inhibit glutaminase in humans.

GSH depletion liposome adjuvant for augmenting the photothermal immunotherapy of breast cancer.

The high redox level of tumor microenvironment inhibits the oxidation treatment and the immune response. Here, we innovatively develop maleimide liposome (ML) adjuvants to promote immunogenic cell death (ICD) induction and dendritic cells (DCs) maturation by glutathione (GSH) depletion for augmenting the photothermal immunotherapy of breast cancer. The ML effectively depletes the intracellular GSH and up-regulates reactive oxygen species (ROS) in both tumor cells and DCs. In tumor cells, the ROS boosted the ABTS·+ production to activate photothermal-induced ICD. In DCs, it relieved the immunosuppression, promoting DC maturation (57%) and antigen presenting. As a result of the ML assistant, the therapeutic systems improved the infiltration of CD8+ T cells to 53% in tumor tissues, eliciting strong abscopal effect and antimetastasis effect. The MLs were believed to be a superior candidate of adjuvants for enhancing immune response and cancer therapeutic efficacy.

MicroRNA let-7g-5p alleviates murine collagen-induced arthritis by inhibiting Th17 cell differentiation.

Rheumatoid arthritis (RA) is a chronic and systemic autoimmune disease with complicated pathogenesis. IL-17-producing T helper cells (Th17) are important players in the RA process. Despite numerous researches have proven that microRNAs (miRNAs) are crucial to regulate autoimmune diseases including RA, the effect of miRNAs on Th17 cell differentiation and function in the RA progress is not clear. Here, our results showed that the expression of miRNA let-7g-5p was substantially lower in RA patients and CIA mice compared with healthy controls, accompanied by the increased Th17 cell population. Furthermore, the inhibition of let-7g-5p on Th17 cell differentiation and function were verified in vitro. Notably, the disease severity in CIA mice was significantly alleviated after the treatment of let-7g-5p mimics. In addition, let-7g-5p mimics treatment markedly down-regulated the frequency of Th17 cells in CIA mice. Taken together, our findings indicate that let-7g-5p can ameliorate CIA through blocking the differentiation of Th17 cells, which may be a novel strategy to treat autoimmune diseases such as RA.

Zishen Tongluo formula ameliorates collagen-induced arthritis in mice by modulation of Th17/Treg balance.

ETHNOPHARMACOLOGICAL RELEVANCE: Zishen Tongluo formula (ZTF) is simplified from the Qingluo Tongbi formula, which has been applied to treat rheumatoid arthritis (RA) in clinical practices for several decades. Our previous studies have verified the effects of ZTF on arthritis animal models. However, its mechanism of treating RA is not clear. AIM OF THE STUDY: The present study was designed to investigate the effects of ZTF on the Th17/Treg balance in RA mice and the role of the different herb groups with the effect of Zishen yangyin (YY), Huatan quyu (HT), or Qufeng chushi (QF) in ZTF. MATERIALS AND METHODS: A mouse model of collagen-induced arthritis (CIA) was established. The animals were randomly divided into the normal, model, positive drug, YY, QF, HT, and the whole compound (ZTF) groups. After oral administration for one-month, cytokine levels in the plasma and histopathological changes of the joint were measured by ELISA and hematoxylin-eosin staining, respectively. Meanwhile, the balance of Th17/Treg cells in blood, spleen or lymph nodes was detected using flow cytometry and qPCR. RESULTS: ZTF or the different functional groups could improve the joint inflammation, decrease the levels of proinflammatory cytokines, restore the balance of Th17 and Treg cells in CIA mice. However, there were some differences in each functional group: YY mainly promoted the responses of Treg cells while QF inhibited the functions of Th17 cells. Besides, HT regulated both Th17 and Treg cells to keep the immune balance. CONCLUSIONS: ZTF could notably ameliorate CIA mice by restoring the balance of Th17/Treg cells. Each functional group could target Th17 and/or Treg cells to produce synergistic/enhancement effects, and ZTF had a better holistic effect in RA treatment.

Th17 cell pathogenicity and plasticity in rheumatoid arthritis.

CD4+ Th cells play an important role in the development of rheumatoid arthritis (RA) by regulating adaptive immune response. As major subsets of CD4+ Th cells, Th17 cells can produce a large number of hallmark cytokines such as IL-17A and IL-17F, which participate in host defense and immune homeostasis. However, increasing researches have shown that Th17 cells are unstable and exhibit a certain degree of plasticity, which aggravates their pathogenicity. Furthermore, the plasticity and pathogenicity of Th17 cells are closely related with the disease activity in RA. In this paper, the characteristics including phenotype, differentiation, plasticity, and pathogenicity of Th17 cells in RA will be systematically summarized. This will contribute to clarify the immunologic mechanism of RA and further provide a novel strategy for the clinical treatment of autoimmune diseases.