Stone et al. describe an inexpensive, clinically translatable photoreceptor isolation strategy for the production of cell therapies to treat inherited blindness. The cover image shows cells dissociated from an iPSC-derived retinal organoid, stained for neural retina-specific leucine zipper protein (NRL, green) and arrestin 3 (ARR3, red). Nuclei are stained with DAPI (blue).
Background & Aims Liver cirrhosis is characterized by chronic inflammation and fibrosis, with Th17 cells playing a crucial role in its progression. Recent evidence suggests that dietary salt influences immune diseases by modulating Th17 differentiation. This study assessed the impact of dietary salt on Th17-driven inflammation in patients with compensated cirrhosis and explored its effects on liver injury in mouse models. Methods A non-drug, open-label, non-randomized study involved 37 patients with compensated cirrhosis, who were given personalized guidelines to reduce salt intake over three months. Changes in Th17-driven inflammation and liver function markers were assessed at baseline and after salt restriction. In parallel, the impact of a high-salt diet on hepatic CD4+ T cells was analyzed in mouse models of acute liver injury and fibrosis. Results High salt intake was associated with Th17-mediated inflammation and correlated with markers of impaired liver function in these patients. Importantly, moderating salt intake through a personalized nutritional intervention was sufficient to reduce CD4+ T cell- mediated inflammation. Furthermore, analysis of RNA-seq data revealed enrichment of salt-induced Th17 gene signatures in both liver tissue and peripheral cells from patients with liver disease. Similarly, mice fed a high salt diet showed hepatic enrichment of Th17 cells and exacerbated liver fibrosis upon injury. Mechanistic studies revealed that high sodium conditions activated NF-κB and induced IL-6 production in hepatocytes, which may promote Th17 responses. Conclusion Dietary salt exacerbates Th17-driven inflammation and contributes to cirrhosis progression. Salt reduction may represent a viable therapeutic approach to manage inflammation in compensated cirrhosis.
Amalia Tzoumpa, Beatriz Lozano-Ruiz, Yin Huang, Joanna Picó, Alba Moratalla, María Teresa Pomares, Iván Herrera, Juanjo Lozano, María Rodríguez-Soler, Cayetano Miralles, Pablo Bellot, Paula Piñero, Fabián Tarín, Pedro Zapater, Sonia Pascual, José Manuel González-Navajas
Heterozygosity for missense mutations in one of 3 seemingly redundant calmodulin (CALM)-encoding genes can cause life-threatening arrhythmias, suggesting that small fractions of mutant CALM protein suffice to cause a severe phenotype. However, the exact molar ratios of wildtype to mutant CALM protein in calmodulinopathy hearts remain unknown. The aim of the present study was to quantitate mutant versus wildtype CALM transcript and protein levels in hearts of knock-in mice harboring the p.N98S mutation in the Calm1 gene. We found that the transcripts from the mutant Calm1 allele were the least abundantly expressed Calm transcripts in both hetero- and homozygous mutant hearts, while mutant hearts accumulate high levels of N98S-CALM protein in a Calm1N98S allele dosage-dependent manner, exceeding those of wildtype CALM protein. We further show that the severity of the electrophysiological phenotype incrementally increases with the graded increase in the mutant-to-wildtype CALM protein expression ratio seen in homozygous versus heterozygous mutant mice. We finally show a decrease in N98S-CALM protein degradation, suggesting that mutant CALM stabilization contributed to its enrichment in the heart. Our results support what we believe to be a novel mechanism by which a mutation in a single Calm gene can give rise to a severe phenotype.
Wen-Chin Tsai, Chiu-Fen Yang, Shu-Yu Lin, Suh-Yuen Liang, Wei-Chung Tsai, Shuai Guo, Xiaochun Li, Susan Ofner, Kai-Chien Yang, Tzu-Ching Meng, Peng-Sheng Chen, Michael Rubart
Multidrug-resistant (MDR) bacterial pneumonias pose a critical threat to global public health. The opportunistic Gram-negative pathogen Pseudomonas aeruginosa is a leading cause of nosocomial-associated pneumonia, and an effective vaccine could protect vulnerable populations, including the elderly, immunocompromised, and those with chronic respiratory diseases. Highly heterogeneous outer membrane vesicles (OMVs), shed from Gram-negative bacteria, are studded with immunogenic lipids, proteins, and virulence factors. To overcome limitations in OMV stability and consistency, we described a believed to be novel vaccine platform that combines immunogenic OMVs with precision nanotechnology—creating a bacterial cellular nanoparticle vaccine candidate (CNP), termed Pa-STING-CNP, which incorporates an adjuvanted core that activates the STING (stimulator of interferon genes) pathway. In this design, OMVs are coated onto the surface of self-adjuvanted STING nanocores. Pa-STING CNP vaccination induced substantial antigen presenting cell recruitment and activation in draining lymph nodes, robust anti-Pseudomonas antibody responses, and provided protection against lethal challenge with the hypervirulent clinical P. aeruginosa isolate PA14. Antibody responses mediated this protection and provided passive immunity against the heterologous P. aeruginosa strain PA01. These findings provided evidence that nanotechnology can be used to create a highly efficacious vaccine platform against high priority MDR pathogens such as P. aeruginosa.
Elisabet Bjånes, Nishta Krishnan, Truman Koh, Anh T.P. Ngo, Jason Cole, Joshua Olson, Ingrid Cornax, Chih-Ho Chen, Natalie Chavarria, Samira Dahesh, Shawn M. Hannah, Alexandra Stream, Jiaqi Amber Zhang, Hervé Besançon, Daniel Sun, Siri Yendluri, Sydney Morrill, Jiarong Zhou, Animesh Mohapatra, Ronnie H. Fang, Victor Nizet
More than one third of patients with glioblastoma experience tumour progression during adjuvant therapy. In this study, we performed a high-throughput drug repurposing screen of FDA-approved agents capable of crossing the blood-brain barrier that to find agents to counteract acquired or inherent glioma cell resistance to temozolomide-associated cytotoxicity. We identified the cholesterol processing inhibitor, lomitapide, as a potential chemosensitizer in glioblastoma. In vitro treatment of temozolomide-resistant glioblastoma cells with lomitapide resulted in decreased intracellular ubiquinone levels and sensitized cells to temozolomide-induced ferroptosis. Concomitant treatment with lomitapide and temozolomide (TMZ) prolonged survival and delayed tumour recurrence in a mouse glioblastoma model, compared to treatment with TMZ alone. Our data identified lomitapide as a potential adjunct for treatment of temozolomide-resistant glioblastoma.
Alyona Ivanova, Taylor M. Wilson, Kimia Ghannad-Zadeh, Esmond Tse, Robert Flick, Megan Wu, Sunit Das
Parathyroid hormone (PTH) regulates serum calcium and phosphate through its actions in bone and the kidney and is used to increase bone in osteoporosis treatment. In bone, PTH targets osteoblasts and osteocytes to regulate bone remodeling but also bone marrow stromal cells (BMSCs), regulating their differentiation in the osteoblast and/or the adipocyte lineages. PTH exerts its action through the PTH/PTH-related peptide (PTHrP) receptor (PTH1R), a G protein-coupled receptor (GPCR), activating adenylyl cyclase and phospholipase C (PLC). Although the effects of cAMP and PKA are well characterized, little is known about the effects of PLC activation or on the cross-talk between PTH signaling and other pathways. Here, bulk RNA-seq of PTH-treated murine BMSC line (W-20) revealed significant changes in the Hippo pathway. PTH stabilized YAP, a key target of Hippo, by decreasing YAP/LATS1 interaction, YAPS127 phosphorylation and YAP ubiquitination, leading to YAP nuclear translocation and expression of YAP target genes. Similar events occurred in osteocyte cell lines. This occurred via an increase in Src kinase activity: we identified YAPY428 as a key tyrosine residue phosphorylated by Src in response to PTH. Preventing YAP428 phosphorylation led to YAP instability, blocking both osteogenic and adipogenic differentiation of W-20 cells. These results demonstrate active crosstalk between the PTH/PTHrP and the Hippo signaling pathways and reveal that PTH signaling utilizes the PLC-Ca2+-Src tyrosine kinase signaling cascade to influence YAP stability, antagonizing Hippo signaling and favoring stromal cell differentiation. Thus, PTH signaling counteracts the effects of Hippo signaling in BMSCs to favor their differentiation.
Sara Monaci, Mengrui Wu, Hiroyuki Okada, Kedkanya Mesil, Byeong-Rak Keum, Maisa Monseff Rodrigues da Silva, Clifford J. Rosen, Francesca Gori, Roland Baron