Intestinal CXCR6+ ILC3s migrate to the kidney and exacerbate renal fibrosis via IL-23 receptor signaling enhanced by PD-1 expression.

Group 3 innate lymphoid cells (ILC3s) regulate inflammation and tissue repair at mucosal sites, but whether these functions pertain to other tissues-like the kidneys-remains unclear. Here, we observed that renal fibrosis in humans was associated with increased ILC3s in the kidneys and blood. In mice, we showed that CXCR6+ ILC3s rapidly migrated from the intestinal mucosa and accumulated in the kidney via CXCL16 released from the injured tubules. Within the fibrotic kidney, ILC3s increased the expression of programmed cell death-1 (PD-1) and subsequent IL-17A production to directly activate myofibroblasts and fibrotic niche formation. ILC3 expression of PD-1 inhibited IL-23R endocytosis and consequently amplified the JAK2/STAT3/RORγt/IL-17A pathway that was essential for the pro-fibrogenic effect of ILC3s. Thus, we reveal a hitherto unrecognized migration pathway of ILC3s from the intestine to the kidney and the PD-1-dependent function of ILC3s in promoting renal fibrosis.

Gasdermin D deficiency aborts myeloid calcium influx to drive granulopoiesis in lupus nephritis.

Gasdermin D (GSDMD) is emerging as an important player in autoimmune diseases, but its exact role in lupus nephritis (LN) remains controversial. Here, we identified markedly elevated GSDMD in human and mouse LN kidneys, predominantly in CD11b+ myeloid cells. Global or myeloid-conditional deletion of GSDMD was shown to exacerbate systemic autoimmunity and renal injury in lupus mice with both chronic graft-versus-host (cGVH) disease and nephrotoxic serum (NTS) nephritis. Interestingly, RNA sequencing and flow cytometry revealed that myeloid GSDMD deficiency enhanced granulopoiesis at the hematopoietic sites in LN mice, exhibiting remarkable enrichment of neutrophil-related genes, significant increases in total and immature neutrophils as well as granulocyte/macrophage progenitors (GMPs). GSDMD-deficient GMPs and all-trans-retinoic acid (ATRA)-stimulated human promyelocytes NB4 were further demonstrated to possess enhanced clonogenic and differentiation abilities compared with controls. Mechanistically, GSDMD knockdown promoted self-renewal and granulocyte differentiation by restricting calcium influx, contributing to granulopoiesis. Functionally, GSDMD deficiency led to increased pathogenic neutrophil extracellular traps (NETs) in lupus peripheral blood and bone marrow-derived neutrophils. Taken together, our data establish that GSDMD deletion accelerates LN development by promoting granulopoiesis in a calcium influx-regulated manner, unraveling its unrecognized critical role in LN pathogenesis.

Knockout of integrin αvß6 protects against renal inflammation in chronic kidney disease by reduction of pro-inflammatory macrophages.

Integrin αvß6 holds promise as a therapeutic target for organ fibrosis, yet targeted therapies are hampered by concerns over inflammatory-related side effects. The role of αvß6 in renal inflammation remains unknown, and clarifying this issue is crucial for αvß6-targeted treatment of chronic kidney disease (CKD). Here, we revealed a remarkable positive correlation between overexpressed αvß6 in proximal tubule cells (PTCs) and renal inflammation in CKD patients and mouse models. Notably, knockout of αvß6 not only significantly alleviated renal fibrosis but also reduced inflammatory responses in mice, especially the infiltration of pro-inflammatory macrophages. Furthermore, conditional knockout of αvß6 in PTCs in vivo and co-culture of PTCs with macrophages in vitro showed that depleting αvß6 in PTCs suppressed the migration and pro-inflammatory differentiation of macrophages. Screening of macrophage activators showed that αvß6 in PTCs activates macrophages via secreting IL-34. IL-34 produced by PTCs was significantly diminished by αvß6 silencing, and reintroduction of IL-34 restored macrophage activities, while anti-IL-34 antibody restrained macrophage activities enhanced by αvß6 overexpression. Moreover, RNA-sequencing of PTCs and verification experiments demonstrated that silencing αvß6 in PTCs blocked hypoxia-stimulated IL-34 upregulation and secretion by inhibiting YAP expression, dephosphorylation, and nuclear translocation, which resulted in the activation of Hippo signaling. While application of a YAP agonist effectively recurred IL-34 production by PTCs, enhancing the subsequent macrophage migration and activation. Besides, reduced IL-34 expression and YAP activation were also observed in global or PTCs-specific αvß6-deficient injured kidneys. Collectively, our research elucidates the pro-inflammatory function and YAP/IL-34/macrophage axis-mediated mechanism of αvß6 in renal inflammation, providing a solid rationale for the use of αvß6 inhibition to treat kidney inflammation and fibrosis.

Nocebo response intensity and influencing factors in the randomized clinical trials of irritable bowel syndrome: A systematic review and meta-analysis.

Objective: To estimate the magnitude of the nocebo response and explore its influencing factors in irritable bowel syndrome (IBS). Methods: The PubMed, Embase, and Cochrane Library databases were searched up to March 2021. We performed a random effects meta-analysis of the proportion of adverse events (AEs) in placebo-treated patients with IBS who are involved in parallel-designed, randomized, placebo-controlled trials investigating pharmacological interventions and evaluated the effect of trial characteristics on the magnitude of the nocebo response rate. Results: A total of 6,107 studies were identified from the databases. After evaluation, 53 met the eligibility criteria and were included. The overall pooled nocebo response rate was 32% (95% CI: 26-38%). The most commonly reported AEs were headache (9%), nasopharyngitis (7%), abdominal pain (4%), and nausea (4%). The nocebo response rate was low compared with that in the treatment group applying probiotics, antispasmodics, and Traditional Chinese medicine, but high compared with that in antibiotic treatment group. The nocebo rate in patients using diaries to record AEs was lower than the average, and was higher in patients recording through checkup. Discussion: Patients with IBS have significant nocebo response intensity in clinical trials. Based on findings in this study, we recommend the researchers pay attention to the common AEs and carefully analyze the relation to the intervention.