Research
Abstract
Glaucoma is associated with ocular hypertension, and lowering intraocular pressure is the primary objective of current therapies. Recent studies have established a key role for Schlemm’s canal endothelium in this pressure increase and have shown that it has a unique, lymphatic-like hybrid phenotype characterized by expression of the lymphatic transcription factor PROX1. However, the functional importance of this hybrid phenotype in the adult canal remains unclear, as long-term studies have been limited by systemic requirements for lymphatic gene expression and a lack of Schlemm’s canal–specific animal models. Here, we designed and validated a strategy using 4OH-tamoxifen-loaded nanocarriers to generate targeted, Schlemm’s canal-specific Prox1 knockout mice that specifically lacked lymphatic characteristics in the canal endothelium. Within four weeks, intraocular pressure was significantly elevated, and ocular hypertension was maintained for at least 24 weeks. Unlike lymphatic vessels, which degenerate following Prox1 deletion, Schlemm’s canal persisted but reverted to a less functional vein-like phenotype with no change in size or morphology. Together, these findings demonstrate the utility of nanocarrier-mediated tamoxifen delivery and establish the importance of the Schlemm’s canal lymphatic-like phenotype in intraocular pressure regulation, providing targets for future glaucoma therapies and a mouse model of adult-onset ocular hypertension.
Authors
Sofia Lara Ochoa, Hoi-Lam Li, Hyeohn Kim, Zihang Yan, Natalia C. Mendonca, Pan Liu, Hyunjoo J. Lee, Michael P. Vincent, Sultan Almunif, Hao F. Zhang, Haiyan Gong, Evan A. Scott, Mark Johnson, Benjamin R. Thomson
Abstract
TB (Tuberculosis) and HIV co-infection remains a major global health challenge, with limited understanding of how these pathogens impact local immune responses in the lungs. This study is the first to investigate the modulation of IL-21 during LTBI and Mycobacterium tuberculosis (Mtb)/ Simian Immunodeficiency Virus (SIV) co-infection in non-human primates (NHP). We show that IL-21 expression, predominantly derived from CD4⁺ T cells, is significantly reduced in lungs of Mtb/SIV co-infected macaques, especially in the absence of cART. Although cART and cART with 3HP partially restore IL-21-producing CD4⁺ T cells, levels remain below those in LTBI, indicating ongoing immune impairment. Spatial transcriptomic analysis suggests localized alterations in immune signaling, including differences in STAT1- and STAT3-associated transcriptional profiles and reduced Mtb-specific IFN-γ responses in co-infected animals. Together, our findings indicate that IL-21-producing CD4⁺ T cells are selectively and persistently impaired in the lungs during Mtb/SIV co-infection despite antimicrobial and antiviral therapy. These results highlight a compartment-specific deficit in immune reconstitution and suggest that IL-21-associated pathways may warrant further investigation as potential targets for host-directed therapeutic strategies.
Authors
Vinay Shivanna, Renee D. Escalona, Colin Chuba, Shashi Prakash Singh, Ahmed A. Moustafa, J. Quincy Brown, Chenyao Xiao, Sangkyu Kim, Edward J. Dick Jr., Smriti Mehra, Mirko Paiardini, Riti Sharan
Abstract
In metabolic dysfunction-associated steatohepatitis (MASH), liver sinusoidal endothelial cells (LSECs) acquire a proinflammatory phenotype termed lipotoxic endotheliopathy. We previously identified glycogen synthase kinase 3β (GSK3β) as a central signaling hub in LSECs during MASH. To elucidate the molecular mechanisms and functional outcome of lipotoxicity-induced GSK3β activation in LSECs, we utilized endothelial cell-specific Gsk3β knockout (Gsk3β△End) mice fed MASH-inducing diets. Endothelial Gsk3β deletion significantly reduced markers of lipotoxic endotheliopathy, including adhesion molecules and chemokines, alongside liver injury, inflammation, and fibrosis. Immune profiling via flow cytometry and mass cytometry by time of flight (CyTOF) identified decreased hepatic infiltration of proinflammatory myeloid populations, particularly mature dendritic cells (DCs) in Gsk3β△End mice. In a co-culture system, GSK3β in lipotoxic LSECs promoted DCs maturation. Mechanistically, GSK3 inhibition restored lipotoxicity-induced alterations in LSEC mitochondrial morphology and respiration by regulating AMP-activated protein kinase and dynamin-related protein 1. This rescue suppressed chemokines and adhesion molecules expression, thereby limiting immune cell recruitment. Collectively, under lipotoxic stress, GSK3β amplifies mitochondrial dysfunction and inflammatory signaling in LSECs, enhancing myeloid cell homing and DC maturation. Targeting LSEC GSK3β may therefore represent a promising therapeutic strategy to mitigate LSEC driven fibro inflammatory response in human MASH.
Authors
Akitoshi Sano, Qianqian Guo, Khaled Warasnhe, Chady Meroueh, Nantawat Satthawiwat, Asma Hamdi, Ghefar Hmaydoosh, Xin Dai, Usman Yaqoob, Kevin D. Pavelko, Charlene Miciano, Tatiana Kisseleva, Zeba Firdaus, Patrick P. Starlinger, David Pereyra, Enis Kostallari, Petra Hirsova, Davide Povero, Samar H. Ibrahim
Development and characterization of triazole-based WDR5 inhibitors for the treatment of glioblastoma
Abstract
Glioblastoma (GBM) cancer stem cells (CSCs) contribute to tumor recurrence, treatment resistance, and dismal clinical outcomes. Genetic and pharmacological evidence suggests that the nuclear scaffolding protein WD-repeat containing protein 5 (WDR5) is a therapeutic vulnerability of the CSC population. However, previously reported WDR5 inhibitors display low permeability and are unable to penetrate the blood-brain barrier (BBB), limiting their utility in GBM. Herein, we report the structure-guided development of a novel series of triazole-based WDR5 WIN-site inhibitors designed to increase passive brain penetration. We identified triazole-based WDR5 inhibitors that are potent, passively permeable, and in some cases more brain penetrant than other scaffolds. We phenotypically assessed our novel WDR5 inhibitors in a panel of patient-derived CSC models and uncovered unique WDR5-regulated metabolic genes in GBM. We also evaluated their antiproliferative activity against CSCs both in vitro and in vivo. Finally, to identify novel combination opportunities, we screened a 2,100-compound chemical probe library and identified that the ATAD2 inhibitor BAY-850 synergizes with WDR5 inhibitors to enhance CSC killing. Our work diversifies the chemical matter targeting WDR5, clarifies the in vitro consequences of WIN-site inhibition in CSCs, and encourages the future development of next-generation WDR5 inhibitors with the potential to achieve in vivo efficacy in the brain.
Authors
Jesse A. Coker, Steven R. Martinez, Sang Hoon Han, Anthony R. Sloan, Amit Kumar Gupta, George Bukenya, Paul Polzer, James H. Ramos, Emma G. Rico, Annabella Rico, A. Abigail Lindsey, Tanvi Navadgi, Natalie Reitz, Todd Romigh, Jonathan Macdonald, Dhiraj Sonawane, Christopher M. Goins, Christopher G. Hubert, Nancy S. Wang, Feixiong Cheng, Joseph Alvarado, Samuel A. Sprowls, Justin D. Lathia, Shaun R Stauffer
Abstract
Abdominal aortic aneurysm (AAA) lacks effective pharmacological therapies. Here, we investigate transcription factor 7-like 2 (TCF7L2), a genetic locus associated with both thoracic and abdominal aortic aneurysms, to elucidate its role in AAA pathogenesis. Integrating summary-data-based Mendelian randomization (SMR) with single-cell RNA sequencing (scRNA-seq) of human and mouse aortas, we identify TCF7L2 as a gene enriched in vascular smooth muscle cells (VSMCs) and causally linked to AAA development. Smooth muscle cell-specific TCF7L2 knockout significantly attenuates AAA formation across three distinct murine models (Ang II infusion-, BAPN/Ang II co-administration-, and elastase-induced AAA), independent of systemic blood pressure or lipid levels. Mechanistic studies reveal that TCF7L2 directly upregulates MMP14 and downregulates TIMP3 expression in vitro and in vivo, driving MMP2-mediated extracellular matrix (ECM) degradation. Concurrently, TCF7L2 represses integrin β1 (ITGB1) expression, reducing VSMC adhesion to the ECM. Collectively, these findings identify TCF7L2 as a key driver of pathological vascular remodeling in AAA, suggesting that targeting TCF7L2 may offer a novel therapeutic strategy for limiting AAA progression.
Authors
Yongjie Deng, Yaozhong Liu, Yang Zhao, Hongyu Liu, Guizhen Zhao, Zhenguo Wang, Xu Zhang, Chao Xue, Wei Huang, Tianqing Zhu, Haocheng Lu, Yanhong Guo, Lin Chang, Ida Surakka, Y. Eugene Chen, Jifeng Zhang
Abstract
Immune checkpoint inhibitors have transformed cancer therapy, yet many patients fail to achieve durable responses due to insufficient T cell reinvigoration. Cytokines offer promise for enhancing immunotherapy, but their clinical use is limited by toxicity and a narrow therapeutic index. Immunocytokines, engineered fusion proteins combining antibody specificity with cytokine activity, aim to overcome these challenges by targeting cytokine delivery to immune cells or the tumor microenvironment. We describe SAR445877 (SAR’877), a novel PD-1-targeted immunocytokine that fuses a high-affinity anti-PD-1 antibody with a detuned IL-15/IL-15Rα sushi domain complex. SAR’877 blocks PD-1/PD-L1 and PD-1/PD-L2 interactions while selectively delivering IL-15 signals to PD-1+ T cells, enhancing proliferation and activation of antigen-experienced CD8+ and CD4+ T cells and NK cells, while minimizing systemic inflammation. Mechanistically, SAR’877 activates STAT5 signaling in PD-1+ lymphocytes and restores effector function in exhausted T cells. In preclinical models, a murine surrogate of SAR’877 accelerated viral clearance and induced robust anti-tumor immunity by expanding cytotoxic CD8+ T cells and promoting Th1 polarization. Notably, SAR’877 outperformed anti-PD-1 plus untargeted IL-15, highlighting the therapeutic potential of targeted IL-15 delivery. These findings position SAR’877 as a promising next-generation immunotherapy with enhanced efficacy and reduced cytokine-associated toxicities.
Authors
Isaraphorn Pratumchai, Marie Bernardo, Julien Tessier, Jaroslav Zak, Kristi L. Marquardt, Joon Sang Lee, Maheeka Bimal, AHyun Choi, Anthony M. Byers, Mikielia G. Devonish, Roberto Carrio, Dan Lu, Stella A. Martomo, Jeegar Patel, Yu-an Zhang, Ingeborg M. Langohr, Virna Cortez-Retamozo, Dinesh S. Bangari, Angela Hadjipanayis, Xiangming Li, Valeria R. Fantin, Donald R. Shaffer, John R. Teijaro
Abstract
Germline BRCA1/2 pathogenic variant (PV) carriers have elevated young-onset breast cancer risk. To define the pretreatment genomic landscapes of young-onset gBRCA-associated breast cancer, we evaluated 136 treatment-naïve tumors diagnosed before age 50 (92.6% ≤40): gBRCA1 86(63.2%); gBRCA2 50(36.8%) in the prospective POSH study, and 66 noncarriers from The Cancer Genome Atlas. Using whole exome sequencing, we analyzed somatic variation, allele-specific loss of heterozygosity (asLOH), homologous recombination deficiency (HRD), and single-base substitution signatures (SBS). gBRCA1(93%) and gBRCA2(96%) breast cancers had high rates of asLOH, but differed significantly in average HRD scores (57.4 ± 1.3 vs 43.7 ± 1.5, P < 0.0001) and median SBS composition (%): SBS1 (aging-associated) 12.9 vs 7.3, P = 0.013; SBS18 (reactive oxygen species [ROS]-associated) 1.4 vs 0, P = 0.007; and SBS3 (HRD-associated) 27.3 vs 42.6, P = 0.002. Compared to gBRCA2 tumors, gBRCA1 tumors with asLOH were significantly enriched for alterations in Hallmark ROS, DNA repair, and epithelial-mesenchymal transition pathways. In ER-positive, HER2-negative tumors from gBRCA1/2 carriers compared to noncarriers, we found significant enrichment of RB1 (OR:6.3;95%CI:2.8–15.4;padj = 0.001), TP53 (OR:4.6;95%CI:1.9–12.1;padj = 0.017), FAT1 (OR:3.9;95%CI:1.84–8.7;padj = 0.013), and MYC (OR:4.0;95%CI:1.8–9.1;padj = 0.017) SNV/indels/CNVs, associated with CDK4/6i resistance. Together, these findings demonstrate significant differences between gBRCA1 and gBRCA2-associated breast cancers, and preexisting CDK4/6i resistance mechanisms supporting prospective trials with individualized therapy for gBRCA1 vs gBRCA2 carriers, and comparing PARPi to CDK4/6i for ER-positive gBRCA1/2-associated breast cancer.
Authors
Mwangala P. Akamandisa, Mingyi Xia, Wilson Cheah, Bradley Wubbenhorst, Kurt P. D'Andrea, Mengyao Fan, Jake S. Shilan, Dana Pueschl, Anupma Nayak, Hayley McKenzie, William Tapper, Ellen R. Copson, Ramsey I. Cutress, Susan M. Domchek, Diana M. Eccles, Katherine L. Nathanson
Abstract
CHI3L1, a chitinase-like protein, is implicated in pulmonary fibrosis, yet its mechanisms incompletely understood. In this study, we demonstrated that CHI3L1 coordinates profibrotic macrophage activation and invasive myofibroblast differentiation, and their crosstalk. In vitro, CHI3L1 drove M2-like macrophage polarization as evidenced by increased CD163, CD206, and PD-L1, and amplified TGF-β1-induced fibroblast responses, including myofibroblast transformation, migration, and invasion. Mechanistically, CHI3L1 enhanced TGF-β1 signaling through SMAD, AKT, and ERK pathways, and PD-L1 was required for CHI3L1/TGF-β1-driven myofibroblast transformation. Co-culture studies further demonstrated the ability of CHI3L1 to induce profibrotic macrophage activation that enhanced myofibroblast transformation mediated via a CD44–PD-L1 axis. In vivo, following bleomycin challenge, CHI3L1 transgenic mice exhibited increased PD-L1+ M2 macrophages, PD-L1+/PDGFRα+ fibroblasts, and PD-1+ immune cells compared with wild-type controls. Therapeutically, combined anti-CHI3L1 and anti-PD-1 antibodies, as well as a bispecific anti-CHI3L1-anti-PD-1 antibody, produced greater anti-fibrotic efficacy than monotherapy. These findings demonstrate crosstalk between CHI3L1 and the PD-1/PD-L1 pathway that promotes profibrotic macrophage activation and invasive fibroblast differentiation and support dual targeting of CHI3L1 and PD-1/PD-L1 as a promising therapeutic strategy for pulmonary fibrosis.
Authors
Han-Seok Jeong, Takayuki Sadanaga, Joyce H. Lee, Suchitra Kamle, Bing Ma, Yang Zhou, Sung Jae Shin, Jack A. Elias, Chun Geun Lee
Abstract
Aortic dissection or rupture is a leading cause of mortality in vascular Ehlers-Danlos syndrome (VEDS), a disorder caused by mutations in the COL3A1 gene. Col3a1G938D/+ mice recapitulate features of VEDS, including high risk of aortic rupture. As in people with VEDS, aortic risk in this model accelerates at the onset of puberty, especially in males. We identify developmentally regulated gene programs associated with this vulnerability and that are targeted by treatments that mitigate aortic risk. Both genetic and pharmacological inhibition of the androgen receptor (AR) eliminated survival differences between sexes, while treatment with a dual AR and mineralocorticoid receptor (MR) antagonist provided near-complete and durable protection in both sexes. Pathways targeted by dual AR/MR inhibition, including those related to extracellular matrix (ECM) organization and cell-ECM interactions, largely overlapped with those also modulated by isolated MR antagonism. Selective targeting of MR signaling emerged as an effective therapeutic strategy in both sexes that avoids sexual side effects in males.
Authors
Emily E. Juzwiak, Caitlin J. Bowen, Rhiannon Edwards, Leda Restrepo, Serena Lee, Cassie A. Parks, Anthony Zeng, Maya M. Black, Oscar E. Reyes Gaido, Emily E. Bramel, Dustin T. Shigaki, Michael A. Beer, Chiara Bellini, Harry C. Dietz, Elena Gallo MacFarlane
Abstract
Eosinophilic esophagitis (EoE) is a type 2 allergic disease characterized by esophageal inflammation and epithelial cell dysfunction. The acquired loss of the anti-serine protease of kazal type 7 (SPINK7) in the squamous epithelium of the esophagus has a causal role in EoE pathogenesis. Yet there is a limited understanding of the factors that regulate its expression and responsiveness to inflammatory stimuli. Herein, we have identified the transcription factor, ovo like transcriptional repressor 1 (OVOL1) as an esophageal selective gene product that regulates SPINK7 promoter activity. Overexpression of OVOL1 increased SPINK7 expression, whereas its depletion decreased SPINK7 expression, impaired epithelial barrier and increased production of the pro-atopy cytokine thymic stromal lymphopoietin (TSLP). Stimulation with IL-13 abrogated the nuclear translocation of OVOL1 and promoted enhanced degradation of OVOL1 protein. This effect of IL-13 was dependent on the esophageal specific cysteine protease calpain-14 at least in part. Analysis of human esophageal biopsies demonstrated that the expression of esophageal OVOL1 correlated with SPINK7 transcript expression and was lost as a function of EoE disease activity. In summary, our study identifies key regulatory mechanisms in EoE pathogenesis, demonstrating that OVOL1 promotes SPINK7 transcription, whereas IL-13 suppresses this pathway in EoE.
Authors
Nurit P. Azouz, Andrea M. Klingler, Sierra S. Beach, Kalen A. Rossey, Mark Rochman, Misu Paul, Julie M. Caldwell, Michael Brusilovsky, Alexander T. Dwyer, Xiaoting Chen, Daniel Miller, Carmy Forney, Leah C. Kottyan, Matthew T. Weirauch, Marc E. Rothenberg
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