Probes for INS

Chemotherapy-Induced Peripheral Neuropathy (CIPN) is a common, dose-limiting side effect of cancer therapy. Protease-activated receptor 2 (PAR2) is implicated in a variety of pathologies, including CIPN. In this study, we demonstrate the role of PAR2 expressed in sensory neurons in a paclitaxel (PTX)-induced model of CIPN in mice. PAR2 knockout/WT mice and mice with PAR2 ablated in sensory neurons were treated with paclitaxel administered via intraperitoneal injection. In vivo behavioral studies were done in mice using von Frey filaments and the Mouse Grimace Scale. We then examined immunohistochemical staining of dorsal root ganglion (DRG) and hind paw skin samples from CIPN mice to measure satellite cell gliosis and intra-epidermal nerve fiber (IENF) density. Pharmacological reversal of CIPN pain was tested with the PAR2 antagonist C781. Mechanical allodynia caused by paclitaxel treatment was alleviated in PAR2 knockout mice of both sexes. In the PAR2 sensory neuronal conditional knockout (cKO) mice, both mechanical allodynia and facial grimacing were attenuated in mice of both sexes. In the dorsal root ganglion of the paclitaxel-treated PAR2 cKO mice, satellite glial cell activation was reduced compared to control mice. IENF density analysis of the skin showed that the paclitaxel-treated control mice have a reduction in nerve fiber density while the PAR2 cKO mice had a comparable skin innervation as the vehicle-treated animals. Similar results were seen with satellite cell gliosis in the DRG where gliosis induced by PTX was absent in PAR cKO mice. Finally, C781 was able to transiently reverse established PTX-evoked mechanical allodynia. PERSPECTIVE: Our work demonstrates that PAR2 expressed in sensory neurons plays a key role in paclitaxel-induced mechanical allodynia, spontaneous pain and signs of neuropathy, suggesting PAR2 as a possible therapeutic target in multiple aspects of paclitaxel CIPN.

Recently in vivo and in vitro studies have provided evidence establishing the significance of microRNAs (miRNAs) in both physiological and pathological conditions. In this regard, the role of miRNA-128 (miR-128) in health and diseases has been found, and its critical regulatory role in the context of some viral diseases has been recently identified. For instance, it has been found that miR-128 can serve as an antiviral mediator and significantly limit the replication and dissemination of human immunodeficiency virus type 1 (HIV-1). Besides, it has been noted that poliovirus receptor-related 4 (PVRL4) is post-transcriptionally regulated by miR-128, representing possible miRNA targets that can modulate measles virus infection. Of note, the downregulation of seminal exosomes eca-miR-128 is associated with the long-term persistence of Equine arteritis virus (EAV) in the reproductive tract, and this particular miRNA is a putative regulator of chemokine ligand 16 (C-X-C motif) as determined by target prediction analysis. In this review, the latest information on the role and action mechanism of miR-128 in viral infections will be summarized and discussed in detail.

Primary Sjogren's syndrome (pSS) is a systemic autoimmune inflammatory disease mainly defined by T cell-dominated destruction of exocrine glands. Currently, CD8+T cells were closely related to the pathogenesis of pSS. However, the single-cell immune profiling of pSS and molecular signatures of pathogenic CD8+T cells have not been well elucidated. Our multiomics investigation identified that both T cell and B cell, especially CD8+T cells, were undergoing significant clonal expansion in pSS patients. TCR clonality analysis revealed that peripheral granzyme (GZM) K+CXCR6+CD8+T cells had higher proportion of shared clones with CD69+CD103-CD8+ tissue resident memory T (TRM) cells in labial glands in pSS. CD69+CD103-CD8+TRM cells featured by high expression of GZMK were more active and cytotoxic in pSS compared with their CD103+ counterparts. Peripheral GZMK+CXCR6+CD8+T cells with higher CD122 expression were increased and harbored a gene signature similar to TRM cells in pSS. Consistently, IL-15 was significantly elevated in pSS plasma and showed the capacity to promote differentiation of CD8+T cells into GZMK+CXCR6+CD8+T cells in a STAT5 dependent manner. Taken together, we depicted the immune landscape of pSS and further conducted comprehensive bioinformatics analysis and in vitro experimental investigation to characterize the pathogenic role and differentiation trajectory of CD8+TRM cells in pSS.

Emerging RNA viruses that target the central nervous system (CNS) lead to cognitive sequelae in survivors. Studies in humans and mice infected with West Nile virus (WNV), a re-emerging RNA virus associated with learning and memory deficits, revealed microglial-mediated synapse elimination within the hippocampus. Moreover, CNS-resident memory T (TRM) cells activate microglia, limiting synapse recovery and inducing spatial learning defects in WNV-recovered mice. The signals involved in T cell-microglia interactions are unknown.Here, we examined immune cells within the murine WNV-recovered forebrain using single-cell RNA sequencing to identify putative ligand-receptor pairs involved in intercellular communication between T cells and microglia. Clustering and differential gene analyses were followed by protein validation and genetic and antibody-based approaches utilizing an established murine model of WNV recovery in which microglia and complement promote ongoing hippocampal synaptic loss.Profiling of host transcriptome immune cells at 25 days post-infection in mice revealed a shift in forebrain homeostatic microglia to activated subpopulations with transcriptional signatures that have previously been observed in studies of neurodegenerative diseases. Importantly, CXCL16/CXCR6, a chemokine signaling pathway involved in TRM cell biology, was identified as critically regulating CXCR6 expressing CD8+ TRM cell numbers within the WNV-recovered forebrain. We demonstrate that CXCL16 is highly expressed by all myeloid cells, and its unique receptor, CXCR6, is highly expressed on all CD8+ T cells. Using genetic and pharmacological approaches, we demonstrate that CXCL16/CXCR6 not only is required for the maintenance of WNV-specific CD8 TRM cells in the post-infectious CNS, but also contributes to their expression of TRM cell markers. Moreover, CXCR6+CD8+ T cells are required for glial activation and ongoing synapse elimination.We provide a comprehensive assessment of the role of CXCL16/CXCR6 as an interaction link between microglia and CD8+ T cells that maintains forebrain TRM cells, microglial and astrocyte activation, and ongoing synapse elimination in virally recovered animals. We also show that therapeutic targeting of CXCL16 in mice during recovery may reduce CNS CD8+ TRM cells.

A high-fat diet (HFD) is a major risk factor for chronic kidney disease. Although HFD promotes renal injury, characterized by increased inflammation and oxidative stress leading to fibrosis, the underlying mechanism remains elusive. Here, we investigated the role and mechanism of protease-activating receptor 2 (PAR2) activation during HFD-induced renal injury in C57/BL6 mice. HFD for 16 weeks resulted in kidney injury, manifested by increased blood levels of blood urea nitrogen, increased levels of oxidative stress with inflammation, and structural changes in the kidney tubules. HFD-fed kidneys showed elevated PAR2 expression level in the tubular epithelial region. To elucidate the role of PAR2, PAR2 knockout mice and their littermates were administered HFD. PAR2 deficient kidneys showed reduced extent of renal injury. PAR2 deficient kidneys showed significantly decreased levels of inflammatory gene expression and macrophage infiltration, followed by reduced accumulation of extracellular matrix proteins. Using NRK52E kidney epithelial cells, we further elucidated the mechanism and role of PAR2 activation during renal injury. Palmitate treatment increased PAR2 expression level in NRK52E cells and scavenging of oxidative stress blocked PAR2 expression. Under palmitate-treated conditions, PAR2 agonist-induced NF-κB activation level was higher with increased chemokine expression level in the cells. These changes were attenuated by the depletion of oxidative stress. Taken together, our results suggest that HFD-induced PAR2 activation is associated with increased levels of renal oxidative stress, inflammatory response, and fibrosis.

The relationship between the human placenta-the extraembryonic organ made by the fetus, and the decidua-the mucosal layer of the uterus, is essential to nurture and protect the fetus during pregnancy. Extravillous trophoblast cells (EVTs) derived from placental villi infiltrate the decidua, transforming the maternal arteries into high-conductance vessels1. Defects in trophoblast invasion and arterial transformation established during early pregnancy underlie common pregnancy disorders such as pre-eclampsia2. Here we have generated a spatially resolved multiomics single-cell atlas of the entire human maternal-fetal interface including the myometrium, which enables us to resolve the full trajectory of trophoblast differentiation. We have used this cellular map to infer the possible transcription factors mediating EVT invasion and show that they are preserved in in vitro models of EVT differentiation from primary trophoblast organoids3,4 and trophoblast stem cells5. We define the transcriptomes of the final cell states of trophoblast invasion: placental bed giant cells (fused multinucleated EVTs) and endovascular EVTs (which form plugs inside the maternal arteries). We predict the cell-cell communication events contributing to trophoblast invasion and placental bed giant cell formation, and model the dual role of interstitial EVTs and endovascular EVTs in mediating arterial transformation during early pregnancy. Together, our data provide a comprehensive analysis of postimplantation trophoblast differentiation that can be used to inform the design of experimental models of the human placenta in early pregnancy.