Kirby et al. show that the oligoadenylate synthetase (OAS)/RNase L pathway, which regulates the innate immune response to viral RNA, represses wound healing and epithelial regeneration. Loss of Rnase L or pharmacological inhibition of downstream signaling enhances regenerative capacity in mice. The cover shows Xenium spatial transcriptomics of Rnasel6-knockout mouse skin captured in Xenium Explorer using graph-based clustering.
Aberrant O-glycosylation of the IgA1 hinge region is a characteristic finding in patients with IgA nephropathy (IgAN) and is thought to contribute to immune-complex formation and kidney injury. Other studies have suggested that abnormalities in mucosal immunity and lymphocyte homing are major contributors to disease. We identified a family with IgAN segregating a heterozygous predicted loss-of-function (LOF) variant in GALNT14, the gene encoding N-acetylgalactosaminyltransferase 14, one of the enzymes involved in mucin-type protein O-glycosylation. While GALNT14 is expressed in IgA1-producing cells, carriers of the LOF variant did not have altered levels of poorly glycosylated IgA1, suggesting other disease mechanisms. Investigation of Galnt14 null mice revealed elevated serum IgA levels and ex vivo IgA production by B cells. These mice developed glomerular IgA deposition with aging and after induction of sterile colitis. Galnt14 null mice also displayed an attenuated mucin layer in the colon and redistribution of IgA-producing cells from mucosal to systemic sites. Adoptive-transfer experiments indicated impaired homing of spleen-derived Galnt14 deficient B lymphocytes, resulting in increased retention in peripheral blood. These findings suggest that abnormalities in O-glycosylation alter mucosal immunity and B lymphocyte homing, pointing to an expanded role of aberrant O-glycosylation in the pathogenesis of IgAN.
Sindhuri Prakash, Nicholas J. Steers, Yifu Li, Elena Sanchez-Rodriguez, Miguel Verbitsky, Isabel Robbins, Jenna Simpson, Sharvari Pathak, Milan Raska, Colin Reily, Anna Ng, Judy Liang, Natalia DeMaria, Amanda Katiraei, Kelsey O'Stevens, Clara Fischman, Samantha Shapiro, Swetha Kodali, Jason McCutchan, Heekuk Park, Djamila Eliby, Marco Delsante, Landino Allegri, Enrico Fiaccadori, Monica Bodria, Maddalena Marasa, Elizabeth Raveche, Bruce A. Julian, Anne-Catrin Uhlemann, Krzysztof Kiryluk, Hong Zhang, Vivette D. D'Agati, Simone Sanna-Cherchi, Jan Novak, Ali G. Gharavi
Maladaptive fear generalization is one of the hallmarks of trauma-related disorders. The endocannabinoid 2-arachidonoylglycerol (2-AG) is crucial for modulating anxiety, fear, and stress adaptation but its role in balancing fear discrimination versus generalization is not known. To address this, we used a combination of plasma endocannabinoid measurement and neuroimaging from a childhood maltreatment-exposed and non-exposed mixed population combined with human and rodent fear conditioning models. Here we show that 2-AG levels are inversely associated with fear generalization at the behavioral level in both mice and humans. In mice, 2-AG depletion increases the proportion of neurons, and the similarity between neuronal representations, of threat-predictive and neutral stimuli within prelimbic prefrontal cortex neuronal ensembles. In humans, increased dorsolateral prefrontal cortical-amygdala resting state connectivity is inversely correlated with fear generalization. These data provide convergent cross-species evidence that 2-AG is a key regulator of fear generalization and further support the notion that 2-AG deficiency could represent a trauma-related disorder susceptibility endophenotype.
Luis E. Rosas-Vidal, Saptarnab Naskar, Leah M. Mayo, Irene Perini, Rameen Masroor, Megan Altemus, Liorimar Ramos-Medina, S. Danyal Zaidi, Hilda Engelbrektsson, Puja Jagasia, Markus Heilig, Sachin Patel
Long-standing hypertension (HTN) affects multiple organs and leads to pathologic arterial remodeling, which is driven by smooth muscle cell (SMC) plasticity. To identify relevant genes regulating SMC function in HTN, we considered Genome Wide Association Studies (GWAS) of blood pressure, focusing on genes encoding epigenetic enzymes, which control SMC fate in cardiovascular disease. Using statistical fine mapping of the KDM6 (JMJD3) locus, we found that rs62059712 is the most likely casual variant, with each major T allele copy associated with a 0.47 mmHg increase in systolic blood pressure. We show that the T allele decreased JMJD3 transcription in SMCs via decreased SP1 binding to the JMJD3 promoter. Using our unique SMC-specific Jmjd3-deficient murine model (Jmjd3flox/floxMyh11CreERT), we show that loss of Jmjd3 in SMCs results in HTN due to decreased EDNRB expression and increased EDNRA expression. Importantly, the Endothelin Receptor A antagonist, BQ-123, reversed HTN after Jmjd3 deletion in vivo. Additionally, single cell RNA-sequencing (scRNA-seq) of human arteries revealed strong correlation between JMJD3 and EDNRB in SMCs. Further, JMJD3 is required for SMC-specific gene expression, and loss of JMJD3 in SMCs increased HTN-induced arterial remodeling. Our findings link a HTN-associated human DNA variant with regulation of SMC plasticity, revealing targets that may be used in personalized management of HTN.
Kevin D Mangum, Qinmengge Li, Katherine Hartmann, Tyler M Bauer, Sonya J. Wolf, James Shadiow, Jadie Y. Moon, Emily Barrett, Amrita Joshi, Gabriela Saldana de Jimenez, Sabrina A. Rocco, Zara Ahmed, Rachael Bogle, Kylie Boyer, Andrea Obi, Frank M Davis, Lin Chang, Lam Tsoi, Johann Gudjonsson, Scott M. Damrauer, Katherine Gallagher
Background: Bacterial vaginosis (BV) is a dysbiosis of the vaginal microbiome that is prevalent among reproductive-age females worldwide. Adverse health outcomes associated with BV include an increased risk of sexually-acquired HIV, yet the immunological mechanisms underlying this association are not well understood. Methods: To investigate BV-driven changes to cervicovaginal tract (CVT) and circulating T cell phenotypes, Kinga Study participants with or without BV provided vaginal tract (VT) and ectocervical (CX) tissue biopsies and PBMC samples. Results: High-parameter flow cytometry revealed an increased frequency of cervical conventional CD4+ T cells (Tconv) expressing CCR5. However, we found no difference in number of CD3+CD4+CCR5+ cells in the CX or VT of BV+ versus BV- individuals, suggesting that BV-driven increased HIV susceptibility may not be solely attributed to increased CVT HIV target cell abundance. Flow cytometry also revealed that individuals with BV have an increased frequency of dysfunctional CX and VT CD39+ Tconv and CX tissue-resident CD69+CD103+ Tconv, reported to be implicated in HIV acquisition risk and replication. Many soluble immune factor differences in the CVT further support that BV elicits diverse and complex CVT immune alterations. Conclusion: Our comprehensive analysis expands on potential immunological mechanisms that may underlie the adverse health outcomes associated with BV including increased HIV susceptibility.
Finn MacLean, Adino Tesfahun Tsegaye, Jessica B. Graham, Jessica L. Swarts, Sarah C. Vick, Nicole B. Potchen, Irene Cruz Talavera, Lakshmi Warrier, Julien Dubrulle, Lena K. Schroeder, Ayumi Saito, Corinne Mar, Katherine K. Thomas, Matthias Mack, Michelle C. Sabo, Bhavna H. Chohan, Kenneth Ngure, Nelly Rwamba Mugo, Jairam R. Lingappa, Jennifer M. Lund
Tumor-associated macrophages (TAMs) are the most prominent immune cell population in the glioblastoma (GBM) tumor microenvironment (TME) and play critical roles in promoting tumor progression and immunosuppression. Here we identified that TAM-derived legumain (LGMN) exhibited a dual role in regulating the biology of TAMs and GBM cells. LGMN promoted macrophage infiltration in a cell-autonomous manner by activating the GSK3b-STAT3 pathway. Moreover, TAM-derived LGMN activated the integrin aV-AKT-P65 signaling to drive GBM cell proliferation and survival. Targeting LGMN-directed macrophage (inhibiting GSK3b and STAT3) and GBM cell (inhibiting integrin aV) mechanisms resulted in an anti-tumor effect in immunocompetent GBM mouse models that was further enhanced when combined with anti-PD1 therapy. Our study reveals a paracrine and autocrine mechanism of TAM-derived LGMN in promoting GBM progression and immunosuppression, providing effective therapeutic targets for improving immunotherapy in GBM.
Lizhi Pang, Songlin Guo, Yuyun Huang, Fatima Khan, Yang Liu, Fei Zhou, Justin D. Lathia, Peiwen Chen
Host-microbe interactions are increasingly recognized for their roles in promoting health as well as in disease pathogenesis. This in-progress series was designed by current JCI Associate Editor Eugene B. Chang to highlight recent advances and challenges in understanding the human microbiome across different organ systems as well as the outlook for microbiome-targeted therapeutics.
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