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SunAh Kang, Andrew J. Monteith, Liubov Arbeeva, Karissa Grier, Shruti Saxena Beem, Anthony C. Trujillo, Xinyun Bi, Kai Sun, Rebecca E. Sadun, Mithu Maheswaranathan, Megan E.B. Clowse, Saira Z. Sheikh, Jennifer L. Rogers, Barbara J. Vilen, SunAh Kang, Andrew J. Monteith, Liubov Arbeeva, Karissa Grier, Shruti Saxena Beem, Anthony C. Trujillo, Xinyun Bi, Kai Sun, Rebecca E. Sadun, Mithu Maheswaranathan, Megan E.B. Clowse, Saira Z. Sheikh, Jennifer L. Rogers, Barbara J. Vilen
Degradation of cellular waste from phagocytosis, endocytosis, and autophagy occurs through hydrolases that become activated during acidification of late endosomes and lysosomes (LELs). In our cross-sectional study, we showed diminished LEL acidification and the accumulation of surface-bound nucleosome on monocytes, dendritic cells, B cells, neutrophils, and T cells from patients with systemic lupus erythematosus (SLE). Diminished acidification and exocytosis of undegraded IgG-immune complexes were evident in active, but not inactive, disease. This was supported by our murine study in which LEL acidification was diminished, promoting exocytosis and the accumulation of cell surface IgG-immune complexes. Mechanistically, LEL dysfunction was induced by chronic PI3K activation in lupus-prone MRL/lpr mice. We also showed that on a non-autoimmune C57BL/6 background, deficiency in SHP-1 and inhibition of SHIP-1 activity were sufficient to recapitulate LEL dysfunction found in MRL/lpr mice. Non-acidic LELs were evident in the majority of patients and associated with SLEDAI arthritis, rash, and nephritis. The high frequency of LEL dysfunction in SLE suggests that it could serve as a biomarker identifying a specific disease endotype.
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Brendan T. Mann, Marta Sanz, Alisha Chitrakar, Kayley Langlands, Marc Siegel, Natalia Soriano-Sarabia, Brendan T. Mann, Marta Sanz, Alisha Chitrakar, Kayley Langlands, Marc Siegel, Natalia Soriano-Sarabia
Latently infected cells persist in people living with HIV (PWH) despite suppressive antiretroviral therapy (ART) and evade immune clearance. “Shock and Kill” cure strategies are hampered by insufficient enhancement of targeted immune responses following latency reversal. We previously demonstrated that autologous Vδ2 T cells from PWH retain anti-HIV activity and can reduce CD4+ T cell reservoirs, although their use in cure approaches is limited due to their dual role as a viral reservoir. However, promising clinical data in oncology shows that their unique MHC-unrestricted antigen recognition affords potent on-target cytotoxicity in the absence of graft-versus-host disease when used as an allogeneic adoptive cell therapy modality. Here, we found expanded allogeneic Vδ2 T cells specifically eliminated HIV-infected CD4+ T cells and monocyte-derived macrophages (MDM), overcoming inherent resistance to killing by other cell types such as NK and CD8+ T cells. Notably, we demonstrated that allogeneic Vδ2 T cells recognized and eliminated the HIV-latent CD4+ T cell reservoir following latency reversal. Our study provides evidence for developing an allogeneic γδ T cell therapy for HIV cure and warrants preclinical investigation in combination approaches.
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Bibhuti Ballav Saikia, Saleena Alikunju, Yemin A. Poovanthodi, Zayan Kassim, P.M. Abdul Muneer, Bibhuti Ballav Saikia, Saleena Alikunju, Yemin A. Poovanthodi, Zayan Kassim, P.M. Abdul Muneer
Oxidative signaling is a central mechanism in alcohol-induced injury and has strong implications for blood-brain barrier (BBB) dysregulation and neuroinflammation. Here, by targeting oxidative signaling, we hypothesized an innovative approach to develop a clinically relevant therapeutic strategy for alleviating alcohol-mediated neurovascular damage. To accomplish this, we enhanced the endogenous activity of nuclear factor E2–related factor 2 (Nrf2) by treatment with a Nrf2 activator III TAT peptide (Nrf2 peptide [NP]) and investigated the neuroprotective role of Nrf2 in promoting antioxidant defense properties and reducing BBB damage and transmigration of leukocytes to the brain following alcohol ingestion. We administered the NP subcutaneously to alcohol-ingested mice and evaluated its therapeutic potential in alleviating alcohol-associated neurovascular impairments. We compared the results with those seen in animals treated with control peptide (random sequence with TAT). The studies showed that the NP treatment preserved the oxidant-antioxidant balance, downregulated ICAM-1 and its receptors, and mitigated BBB damage and leukocyte infiltration into the brain. We validated the effect of the NP in Nrf2-knockout (Nrf2−/−) mice. Thus, this study demonstrates that NP exerts neurovascular protective effects by regulating the oxidant-antioxidant balance, reducing oxidative stress–induced BBB disruption, and limiting transmigration of immune cells to the brain in a mouse model of alcohol ingestion.
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Julia Chini, Nicole DeMarco, Dana V. Mitchell, Sam J. McCright, Kaitlyn M. Shen, Divyansi Pandey, Rachel L. Clement, Jessica Miller, Rajan Jain, Deanne M. Taylor, Mitchell A. Lazar, David A. Hill, Julia Chini, Nicole DeMarco, Dana V. Mitchell, Sam J. McCright, Kaitlyn M. Shen, Divyansi Pandey, Rachel L. Clement, Jessica Miller, Rajan Jain, Deanne M. Taylor, Mitchell A. Lazar, David A. Hill
Dysfunctional white adipose tissue contributes to the development of obesity-related morbidities, including insulin resistance, dyslipidemia, and other metabolic disorders. Adipose tissue macrophages (ATMs) accumulate in obesity and play both beneficial and harmful roles in the maintenance of adipose tissue homeostasis and function. Despite their importance, the molecules and mechanisms that regulate these diverse functions are not well understood. Lipid-associated macrophages (LAMs), the dominant subset of obesity-associated ATMs, accumulate in crown-like structures and are characterized by a metabolically activated and proinflammatory phenotype. We previously identified CD9 as a surface marker of LAMs. However, the contribution of CD9 to the activation and function of LAMs during obesity is unknown. Using a myeloid-specific CD9-KO model, we show that CD9 supports ATM-adipocyte adhesion and crown-like structure formation. Furthermore, CD9 promotes the expression of profibrotic and extracellular matrix remodeling genes. Loss of myeloid CD9 reduces adipose tissue fibrosis, increases visceral adipose tissue accumulation, and improves global metabolic outcomes during diet-induced obesity. These results identify CD9 as a causal regulator of pathogenic LAM functions, highlighting CD9 as a potential therapeutic target for treating obesity-associated metabolic disease.
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Min Zhang, Bin Wang, Ding Sun, Xizhao Chen, Yena Zhou, Jin Yao, Liwen Du, Zehao Zhang, Hao Li, Zeyu Qu, Lu Chen, Qing Luo, Jie Zhang, Xinye Jin, Xiaowei Cheng, Jingxue Niu, Qinrui Xing, Xuezeng Tan, Tao Wang, Jie Liu, Lei Li, Qing Song, Xiangmei Chen, Yizhi Chen, Min Zhang, Bin Wang, Ding Sun, Xizhao Chen, Yena Zhou, Jin Yao, Liwen Du, Zehao Zhang, Hao Li, Zeyu Qu, Lu Chen, Qing Luo, Jie Zhang, Xinye Jin, Xiaowei Cheng, Jingxue Niu, Qinrui Xing, Xuezeng Tan, Tao Wang, Jie Liu, Lei Li, Qing Song, Xiangmei Chen, Yizhi Chen
Heat stroke (HS) is the most severe heat-related emergency, and its pathophysiology remains largely unknown, especially for exertional HS (EHS), which affects younger populations, athletes, and manual workers. Herein, we performed single-cell-transcriptomics, T cell receptor sequencing, and flow cytometry of PBMCs from 9 healthy control participants, 9 patients with heat exhaustion, and 9 patients with EHS to explore complex immunological responses associated with HS pathobiology. We showcased that granzyme-positive T cells and CD56dim NK cells with high cytotoxicity features and IL-1B+NLRP3+ monocytes with high inflammation and pyroptosis scores were enriched in HS, while the CD161+ T cells with innate immune-like, low cytotoxicity, and clonal expansion features were reduced in HS. Importantly, elevated granzyme-positive T and NK cells might interact with monocytes to induce pyroptosis of hepatic and renal cells and target organ injuries, and blocking the NLRP3 inflammasome pathway prior to the induction could alleviate organ injury in HS. This study offers deeper insights into the pathogenesis of HS, supporting the development of optimal treatment strategies.
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Taiki Seki, Jun-Dal Kim, Yasuhito Yahara, Hitoshi Uchida, Keisuke Yaku, Mariam Karim, Teruhiko Makino, Tadamichi Shimizu, Takashi Nakagawa, Taiki Seki, Jun-Dal Kim, Yasuhito Yahara, Hitoshi Uchida, Keisuke Yaku, Mariam Karim, Teruhiko Makino, Tadamichi Shimizu, Takashi Nakagawa
Nicotinamide adenine dinucleotide (NAD+) is essential for cellular metabolism, DNA repair, and stress responses. NAD+ is synthesized from nicotinamide, nicotinic acid (collectively termed niacin), and tryptophan. In humans, deficiencies in these nutrients result in pellagra, marked by dermatitis, diarrhea, and dementia. The dermatitis associated with pellagra typically manifests as photodermatosis in sun-exposed areas. This study examined the effects of NAD+ deficiency on skin homeostasis using epidermis-specific Nampt–conditional KO (Nampt-cKO) mice. These mice displayed substantial NAD+ depletion, reduced poly(ADP-ribose) polymerase (PARP) activity, and increased DNA damage. Consequently, Nampt-cKO mice developed spontaneous skin inflammation and epidermal hyperplasia. RNA-seq and IHC analyses demonstrated increased IL-36 cytokine expression, suggesting that DNA repair–related genomic stress triggers keratinocyte-driven IL-36 production, which promotes inflammation. Furthermore, reduced COL17A1 expression and elevated thymic stromal lymphopoietin (TSLP) levels were observed. NAD+ repletion by transdermal supplementation of nicotinamide mononucleotide (NMN) suppressed the rise of IL-36 levels and skin inflammation. These findings underscore the importance of Nampt-mediated NAD+ metabolism for epidermal stability and indicate that NAD+ depletion may contribute to IL-36–mediated skin inflammation, offering insights for therapeutic strategies in inflammatory skin disorders.
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Hyejin Park, Jung-Eun Park, Bridger H. Freeman, Bosco Seong Kyu Yang, Shun-Ming Ting, Alexander K. Suh, Jude P.J. Savarraj, Shuning Huang, Jakob Körbelin, Huimahn Alex Choi, Sean P. Marrelli, Jaroslaw Aronowski, Peng Roc Chen, Eunhee Kim, Eun S. Park, Hyejin Park, Jung-Eun Park, Bridger H. Freeman, Bosco Seong Kyu Yang, Shun-Ming Ting, Alexander K. Suh, Jude P.J. Savarraj, Shuning Huang, Jakob Körbelin, Huimahn Alex Choi, Sean P. Marrelli, Jaroslaw Aronowski, Peng Roc Chen, Eunhee Kim, Eun S. Park
Mutation of KRAS in endothelial cells (KRAS-ECs) leads to intracerebral hemorrhage (ICH) in brain arteriovenous malformation (bAVM), resulting in severe disabilities or even death. However, it is unclear what causes this hemorrhagic conversion of bAVMs. Here, using a locally established, clinically relevant sporadic bAVM mouse model, created by overexpressing mutant KRAS (KRASG12V) in brain ECs, we demonstrate that KRAS-ECs act as trigger for activation of microglia (MG) and infiltration of macrophages (Mϕ). Using a 3-dimensional immunostaining approach with cleared human and mouse bAVM tissues, we demonstrate an abundance of MG/Mϕ around the bAVM nidus. The presence of MG/Mϕ was correlated to the blood-brain barrier leakage in bAVM areas. Time-lapsed intravital imaging in Cx3cr1-gfp;Ccr2-rfp reporter mice demonstrated the dynamic activation of MG and infiltration of Mϕ toward mutant KRASG12V–modified dysplastic vessels. Importantly, a time-course analysis showed that these activated MG and infiltrated Mϕ are present around the bAVMs prior to hemorrhagic conversion, and controlled depletion of MG/Mϕ reduced ICH incidence in bAVMs. Inhibition of MG/Mϕ with long-term minocycline treatment attenuated the incidence of ICHs around bAVMs. Our study indicates that MG/Mϕ are involved in destabilization of KRASG12V-induced bAVM, leading to hemorrhagic conversion/ICH. Thus, modulation of MG/Mϕ may reduce ICH risk in patients with bAVM.
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Charmi Dedhia, Valentina Villani, Xiaogang Hou, Paolo Neviani, Geremy Clair, Mohammadreza Kasravi, Cristina Grange, Paolo Cravedi, Paola Aguiari, Velia Alcala, Giuseppe Orlando, Xue-Ying Song, Jonathan E. Zuckerman, Roger E. De Filippo, Stefano Da Sacco, Sargis Sedrakyan, Benedetta Bussolati, Laura Perin, Charmi Dedhia, Valentina Villani, Xiaogang Hou, Paolo Neviani, Geremy Clair, Mohammadreza Kasravi, Cristina Grange, Paolo Cravedi, Paola Aguiari, Velia Alcala, Giuseppe Orlando, Xue-Ying Song, Jonathan E. Zuckerman, Roger E. De Filippo, Stefano Da Sacco, Sargis Sedrakyan, Benedetta Bussolati, Laura Perin
Modulation of miRNA expression in glomerular cells is associated with renal disease. Here, we investigated the role of miR-93-5p in mitigating glomerular damage in Alport syndrome and whether the disease-modifying activity of extracellular vesicles from human amniotic fluid stem cells (hAFSC-EVs) is mediated by their miR-93-5p cargo. We identified downregulation of miR-93-5p specifically in glomerular endothelial cells in Alport syndrome along disease progression. Silencing of miR-93-5p in hAFSC-EVs changed the transcriptomic and proteomic profile, regulating EV disease-modifying activity. Compared with naive hAFSC-EVs, silenced hAFSC-EVs did not rescue glomerular endothelial function in vitro and did not restore kidney function in vivo. We established that hAFSC-EVs regulate VEGFR1 and VEGFR2 signaling by miR-93-5p cargo transfer, highlighting that miR-93-5p can restore glomerular endothelial cell biology. Spatial transcriptomics analysis of hAFSC-EV–injected kidneys showed that these EVs can reverse pathways altered during disease progression by stimulating proregenerative processes, specifically in the glomerulus, by regulating miR-93-5p targets. Alteration of glomerular endothelial cell transcriptomics and miR-93-5p targets was also confirmed in biopsies of patients with Alport syndrome using spatial molecular imaging. We demonstrated the critical role of miR-93-5p in glomerular endothelial cells and the capability of hAFSC-EVs to regulate miR-93-5p and its targets in Alport syndrome.
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Fiona Mason, Hui Xiong, Ali Mobeen, Md Saddam Hossain, Sara Mahmudlu, Rosanne Trevail, Mikyal Mobeen, Li Chen, Sunny Lee, Tuncay Delibasi, Jyoti Misra Sen, Mobin Karimi, Fiona Mason, Hui Xiong, Ali Mobeen, Md Saddam Hossain, Sara Mahmudlu, Rosanne Trevail, Mikyal Mobeen, Li Chen, Sunny Lee, Tuncay Delibasi, Jyoti Misra Sen, Mobin Karimi
Alveolar hemorrhage (AH) is a life-threatening condition with high mortality, yet the immunological mechanisms governing disease severity remain poorly defined. Here, we demonstrate a protective role for T cell–intrinsic β-catenin stabilization in AH using a transgenic mouse model (CAT-Tg) in which β-catenin is stabilized under the Lck promoter. We found β-catenin stabilization induced a distinct T cell phenotype marked by expansion of central effector memory cells (CD44+CD122+Eomes+T-bet+) and suppression of proinflammatory signaling, including reduced phosphorylation of STAT1, STAT3, and JAK1. Pristane-induced AH was attenuated in CAT-Tg mice, which exhibited reduced lung injury, decreased proteinuria, and diminished pulmonary proinflammatory cytokine production compared with WT controls. Protection was associated with a marked expansion of FOXP3+ Tregs. Mechanistically, β-catenin stabilization enhanced lung expression of amphiregulin and BATF, mediators of Treg stability and tissue repair. Adoptive transfer of CAT-Tg–derived Tregs into WT mice conferred superior protection against AH, reducing lung inflammation and proteinuria. Transcriptomic analyses revealed enrichment of tissue repair and immune homeostasis pathways, including PI3K-Akt, angiogenesis, and STAT5 signaling. Collectively, these findings identify β-catenin as a regulator of a protective amphiregulin/BATF/Treg axis, highlighting an immunomodulatory pathway with therapeutic potential for AH and inflammatory lung disease.