Glucagon-like peptide-1 (GLP-1) and glucose-induced insulinotropic polypeptide (GIP) receptor agonists have revolutionized obesity therapy but causes for obesity-associated dysregulation of endogenous incretin production remain incompletely understood. Here we show that intestinal transmembrane serine protease 2 (TMPRSS2) plays a pivotal role in deregulating anti-diabetic GLP-1 production in obesity. TMPRSS2 is widely co-expressed in intestinal epithelial cells (IEC) along with its signaling target protease activated receptor 2 (PAR2). In addition to its role in regulating coagulation protease-mediated adipose tissue inflammation, PAR2 signaling in the gut controls postprandial GIP secretion. TMPRSS2, but not the epithelial-expressed proteases FXa or matriptase, activates PAR2 and thereby promotes postprandial GIP release. Accordingly, a PAR2 mutant mouse resistant to TMPRSS2 cleavage is protected from GIP upregulation and diet induced obesity. In the context of obesity, TMPRSS2 also attenuates bioavailability of ghrelin pathway and thereby suppresses GLP-1-mediated control of glucose homeostasis. Pharmacological inhibition or genetic deletion of TMPRSS2 restores ghrelin signaling dependent GLP-1 secretion and GLP-1’s anti-diabetic effects on nutritional glucose homeostasis. Thus, epithelial cell-expressed TMPRSS2, which critically contributes to the lung pathology in SARS-CoV-2 infection, emerges as an intestinal incretin regulator and a potential link between infection and chronic cardiometabolic diseases.
Dilraj Kaur, Sagarika Chakrabarty, Claudius Witzler, Hongjie Wang, Mengwen Wang, Romina Wolz, Petra Wilgenbus, Jens J.N. Posma, P. Sivaramakrishna Rachakonda, Federico Marini, Valeriya V. Zinina, Sabine Reyda, Rajinikanth Gogiraju, Claudine Graf, Fahumiya Samad, Katrin Schäfer, Christoph Reinhardt, Natalia Soshnikova, Wolfram Ruf, Thati Madhusudhan
Dengue virus (DENV) vaccines should be designed to induce balanced protective immunity against all four dengue serotype to mitigate the risk of vaccine-mediated enhanced dengue disease. The first tetravalent vaccine (Dengvaxia) tested in humans was efficacious in children who were partially immune to DENV at baseline. In DENV-naive children, the vaccine was not efficacious and placed some naïve children at risk of experiencing more severe wild-type DENV breakthrough infections. To define dengue vaccine responses at the individual subject level and their relationship to mild and severe dengue infections, we prospectively studied a cohort of DENV-naive children who received one dose of Dengvaxia. The vaccine stimulated variable responses that neutralized 0, 1 (monotypic), or 2+ (multitypic) serotypes in individual children. We used a logistic regression model to evaluate whether vaccine status and serotype-specific NAb status at the end of study period 1 influenced the probability of experiencing a virologically confirmed dengue disease (VCD) case thereafter (months 20 - 60). Vaccinated children with NAb response to only one serotype were at greater risk of being a case compared to the DENV-naïve control group (Odds Ratio 5.07). This risk was not observed in vaccinated children with no NAb or NAb to 2 or more serotypes. We propose that individuals with durable NAb to one serotype have an abundance of serotype cross-reactive, non-neutralizing Abs implicated in the enhanced replication of heterologous serotypes. We discuss the implications of our findings for flagging vaccine candidates that are likely to pose a special risk to seronegative subjects.
Laura J. White, Lindsay D. Hein, Maria Abad Fernandez, Cameron Adams, Elizabeth Adams, Emily Freeman, Ruby Shah, Lakshmanane Premkumar, Kristal An Agrupis, Maria Vinna Crisostomo, Jedas Veronica Daag, Michelle Ylade, Jacqueline Deen, Ana Lena Lopez, Leah Katzelnick, Aravinda M. de Silva
Allogeneic islet transplantation is an effective treatment for type 1 diabetes, but its clinical use is limited by rejection involving innate and adaptive immune responses, requiring life-long immunosuppression. We herein engineered islets by transiently display two immunomodulators chimeric with streptavidin (SA), thrombomodulin (SA-TM) and CD47 (SA-CD47) for localized modulation of both innate and adaptive immune responses. The engineering process did not impact islet viability, glucose responsiveness, and metabolic activity. Intraportal transplantation into allogeneic recipients achieved sustained survival, with 8/11 grafts surviving 120-330 days without immunosuppression. In contrast, non-engineered islets were acutely rejected [median survival time (MST) = 12 days], while islets engineered with SA-TM showed delayed rejection [Median survival time (MST) = 13.5 days], and those with SA-CD47 exhibited prolonged survival (MST = 24 days). Double-engineered islets generated a localized tolerogenic immune environment characterized by low frequencies of inflammatory innate immune cells and increased frequencies of M2 macrophages, myeloid-derived suppressor cells, and CD4+FoxP3+ T regulatory cells. The transcriptomic analysis showed downregulation of proinflammatory and upregulation of immune regulatory pathways. Our results demonstrate that transient co-display of immunomodulatory molecules on the islet surface is a versatile platform with significant translational potential for islet transplantation.
Shadab Kazmi, Mohammad Tarique, Darshan Badal, Vahap Ulker, Ali Turan, Kathleen M. Yee-Flores, Abdalmonam Jadou Nejma, Esma S. Yolcu, Haval Shirwan
BACKGROUND In chronic alcohol consumers, immune cells may drive the progression from mild liver injury to more severe alcohol-associated liver diseases (ALD), including alcohol-associated hepatitis (AAH) and cancer. Liver macrophages, both resident and infiltrating, express Allograft Inflammatory Factor 1 (AIF1), which is upregulated during inflammation and enhances immune activation. METHODS Using serum and urine samples from 868 individuals classified as having alcohol use disorder or not based on DSM-IV/V criteria, along with serum and liver biopsy tissue from a second cohort of 27 patients diagnosed with AAH, we evaluated the impact of the AIF1 promoter single nucleotide polymorphism (SNP) (rs3132451; C/C, C/G, G/G) on liver function markers and immune cell profiles. RESULTS AIF1 transcript levels were genotype-dependent: C/C homozygotes expressed 5.2% of the levels observed in G/G individuals, while C/G heterozygotes expressed 46%. Unlike most SNPs associated with harmful effects, the G/G genotype is highly prevalent, present in ~70% of patients. Among chronic alcohol users, G/G individuals exhibited elevated markers of liver injury and a more than threefold increase in hepatic immune cells, including infiltrating AIF1⁺ macrophages and neutrophils. Despite similar durations of alcohol misuse, G/G individuals had higher Model for End-Stage Liver Disease scores compared to C/G individuals, indicating a significantly greater 90-day mortality risk. Notably, some immune abnormalities, such as elevated neutrophils, persisted in G/G males even after alcohol abstinence. CONCLUSION These findings suggest that functional genetic variation in AIF1 may contribute to the severity and persistence of ALD. TRIAL REGISTRATION ClinicalTrials.gov NCT02231840. FUNDING Research support was provided from the National Institute on Alcohol Abuse and Alcoholism (NIAAA) of the National Institutes of Health (NIH) under grant 1ZIAAA000440-02 and R24AA025017.
Priscila C. Antonello, Colin A. Hodgkinson, Dechun Feng, Cheryl Marietta, Baskar Mohana Krishnan, Maria A. Parra, Zhaoli Sun, Bin Gao, David Goldman, Michelle W. Antoine
Introduction: BK polyomavirus (BKV) infection is associated with injury and subsequent graft loss due to the extent of injury or rejection. However, the molecular mechanisms driving injury and subsequent adverse outcomes remain poorly understood. Methods: In a cross-sectional study, single-cell RNA sequencing from kidney allograft biopsies was used to assess cell type-specific responses between uninfected controls and two distinct phases of BKV infection: peaking (increasing viral blood titers) and resolving (decreasing viral titers following immunosuppression reduction). Results: Genes upregulated in BK viral nephropathy (BKVN) were enriched for polyomavirus infection hallmarks, including ribosome biogenesis, translation, and energy restructuring. Additionally enriched pathways included wound healing, cellular stress, antigen presentation and immune signaling. Even without BKVN (peaking BK viremia alone), epithelial cells expressed signatures for wound healing, cellular stress, and extracellular matrix remodeling. In vivo tubular cell responses at single-cell resolution were validated against single cell transcriptomic data of BKV infected cells in a cell culture model. Despite similarities, in vivo tubular cells underwent metabolic adaptation favoring fatty acid oxidation and proinflammatory responses not observed in culture models likely due to an absent innate and adaptive immune system. Despite lymphopenia and immunosuppressive therapies, the proportion of recipient derived intrarenal adaptive immune cells was increased in biopsies associated with peaking viremia alongside activation of innate immune responses. Adaptive immune cells exhibited persistent inflammatory signaling and remodeling of energy metabolism during the resolving phase of infection. Conclusion: These not previously reported insights into BKV-associated injury may have implications for clinical management and improved allograft outcomes.
Tess Marvin, Rachel Sealfon, Phillip J. McCown, Fadhl AlAkwaa, Evan A. Farkash, Edgar A. Otto, Felix Eichinger, Ping An, Rajasree Menon, Celine C. Berthier, Tavis J. Reed, Paula Arrowsmith, Lalita Subramanian, Kelly J. Shaffer, Silas P. Norman, Ramnika Gumber, Michael J. Imperiale, James M. Pipas, Olga G. Troyanskaya, Matthias Kretzler, Chandra L. Theesfeld, Abhijit S. Naik
Adipocytes exist along a functional spectrum: white adipocytes are energy storing while brown adipocytes have thermogenic capacity such that activation may counteract obesity-related disease. In between are UCP1-expressing beige adipocytes, which can transition between these two energetic states. We previously showed that bone morphogenetic protein 7 (BMP7), a member of the transforming growth factor-β (TGFβ) superfamily, enables differentiation of brown preadipocytes to mature thermogenic cells. To see if immortalized, clonal human white and brown preadipocytes (hWA and hBA, respectively) would become more thermogenic in response to BMP exposure, we treated them with BMP7 or BMP4 for the first 7d of a 30d differentiation protocol. In hBA, absence of either BMP7 or BMP4 led to lower expression of brown-specific markers and oxygen consumption relative to 7d with either BMP. hWA treated for 7d with either BMP did not increase expression of thermogenic protein UCP1 nor induce a brown-like transcription profile. However, BMP-treated hWA produced adipocytes that had higher basal and drug-induced maximal oxygen consumption, which was UCP1-independent and due substantially to the futile creatine cycle (FCC). Our results demonstrate that energetically quiescent human white preadipocytes can be pushed into an energy expending phenotype without transdifferentiation into beige adipocytes, providing a new approach to treat obesity-related metabolic disease.
Kelly T. Long, Cheryl Cero, Sahara L. Ali, Nhuquynh Nguyen, Adrienne R. Guarnieri, Ju Hee Kim, Young Jae Bahn, Jurgen Heymann, Jonathan M. Dreyfuss, Sushil G. Rane, Yu-Hua Tseng, Aaron M. Cypess
BACKGROUND. Transplanting kidneys from donors with HIV to recipients with HIV has become standard clinical practice. However, donors with HIV may have higher prevalence of viral and bacterial infections and autoimmunity that could increase allograft rejection in recipients. METHODS. We included deceased kidney donors (60 with HIV and 41 without HIV) who participated in a multicenter prospective study of HIV kidney transplantation between April 2018-September 2021. Using Phage ImmunoPrecipitation Sequencing, we compared the human antibody repertoire (allergens, autoantibodies, viruses and bacterial toxins) between donors with and without HIV, and evaluated their association with recipient allograft rejection. Moderated t-tests were used to assess reactivity and a multivariate logistic regression model adjusted for donor sex and KDPI assessed the association between donor adenovirus reactivity and recipient allograft rejection. RESULTS. Compared to donors without HIV, donors with HIV had lower BMI and were more likely to be African American. The median number of positive autoantibodies was marginally higher among donors with HIV (499 [IQR = 357, 579]) compared to donors without HIV (395 [IQR = 256, 538] (P = 0.058). Donors with HIV additionally had significantly higher antibody reactivity to Epstein-Barr virus and cytomegalovirus (q < 0.05). Among all donors with and without HIV, antibodies to adenovirus were significantly associated with increased rejection among recipients, including after adjusting for false discovery (q < 0.05) and also adjusting for demographic factors using multivariable logistic regression (odds ratio = 4.97, 95% CI = 1.89–13.61). CONCLUSION. The presence of antibodies to adenovirus infection in kidney donors with HIV may be associated with allograft rejection. TRIAL REGISTRATION. ClinicalTrials.gov NCT03500315. FUNDING. US National Institute of Health
Xianming Zhu, William R. Morgenlander, Diane M. Brown, Yolanda Eby, Megan Morsheimer, Jonah Odim, Serena M. Bagnasco, Meenakshi M. Rana, Sander S. Florman, Rachel J. Friedman-Moraco, Peter G. Stock, Alexander J. Gilbert, Shikha Mehta, Valentina Stosor, Sapna A. Mehta, Marcus R. Pereira, Catherine B. Small, Michele I. Morris, Jonathan Hand, Saima Aslam, Ghady Haidar, Maricar Malinis, Carlos A.Q. Santos, Joanna Schaenman, David Wojciechowski, Karthik M. Ranganna, Emily Blumberg, Nahel Elias, Josa A. Castillo-Lugo, Emmanouil Giorgakis, Senu Apewokin, M. Kate Grabowski, Dorry L. Segev, Andrew D. Redd, Christine M. Durand, H. Benjamin Larman, Aaron A.R. Tobian
The molecular mechanisms responsible for the “atopic march” of allergic skin disease to allergic airway disease are incompletely understood. Secreted phospholipase A2 group X (sPLA2-X) is implicated in human asthma and modulates airway hyperresponsiveness (AHR) and inflammation in murine models of allergic asthma. We developed a complete proteolytic allergen model of dermal sensitization followed by airway challenge to mimic the “atopic march” and examined the role of sPLA2-X in regulating peripheral allergen sensitization, AHR, and airway inflammation. Pla2g10-/- mice receiving both house dust mite (HDM) peripheral sensitization and airway challenge had attenuated AHR relative to WT mice and lower airway eosinophils. Transgenic C57BL/6 PLA2G10 mice (only expressing the human sPLA2-X gene) receiving treatment with a small molecule inhibitor of sPLA2-X (ROC0929) during the dermal sensitization phase demonstrated attenuated AHR and a reduction in lung tissue dust mite-specific tissue resident memory CD4+ T cells. Thus, sPLA2-X acts as an endogenous adjuvant to facilitate allergic sensitization in the periphery, which leads to AHR and airway inflammation following inhalation of the allergen. These results provide proof of concept that inhibition of sensitization in the periphery with a sPLA2-X inhibitor modulates subsequent allergen-induced airway dysfunction.
Ryan C. Murphy, Ying Lai, Yu-Hua Chow, Matt Liu, Brian D. Hondowicz, Dowon An, Marion Pepper, William A. Altemeier, Teal S. Hallstrand
Background: The molecular landscape of lung adenocarcinoma (LUAD) is often illustrated as a driver-oncogene “pie chart,” but identical mutations exhibit heterogeneous signaling shaped by co-mutations, transcriptional programs, and lineage context. We propose a lineage-integrated signaling framework using an EGFR mutation signature (mSig). Methods: We defined EGFR mSig using differentially expressed genes in EGFR-mutant (mt) LUADs. Semi-supervised clustering and machine learning models were used to test reproducibility in different combinations of datasets. We analyzed molecular subtypes, lineage markers, co-occurring mutations and EGFR copy number alterations in EGFR mSig-defined subtypes of LUAD. Results: EGFR mSig showed robust classification performance (AUROC = 0.83-0.95; mean NPV = 96.3%). Validated gene expression subtypes and lung lineage markers were closely aligned with EGFR mSig status. Most EGFR mSig(+) tumors, including many without EGFR mutations belonged to Bronchioid subtype. A subset of canonical RAS mutations were mSig(+) and mirrored the EGFR mutation pattern. EGFR wild-type (WT)/mSig(-) tumors were enriched for non-Bronchioid subtypes and had co-mutations in TP53 or RAS/RAF/RTKs. We highlighted a parsimonious collection of coordinated mutations identified including RAS, KEAP1, STK11, TP53, and CDKN2A, supportive of prior reports. Conclusions: A novel EGFR mSig that captures the transcriptional footprint of EGFR activation revealed a subset of EGFR WT LUADs with “mt-like” features. mSig refines LUAD taxonomy beyond mutation-only pie-chart models by incorporating lineage and co-mutation context. Lineage-directed stratification with co-alteration identifies clinically relevant groups across EGFR and RAS states and highlights new treatment opportunities for patients currently considered “oncogene-negative.” Funding: NCI U01CA272541, R01CA262296, U24CA264021, UG1CA233333, R01CA211939.
Minjeong Kim, Wisut Lamlertthon, Heejoon Jo, Yan Cui, Miyeon Yeon, Hyo Young Choi, Katherine A. Hoadley, Matthew P. Smeltzer, Michele C. Hayward, Matthew D. Wilkerson, Liza Makowski, D. Neil Hayes
Macrophages (MΦ), endowed with remarkable phenotypic plasticity are essential for orchestrating injury responses and regulating iron homeostasis. Given the central role of ferritin heavy chain (FtH) as a molecular rheostat linking iron sequestration to redox-dependent signaling, we examined how myeloid FtH governs renal iron trafficking and ensuing oxidative-stress pathways during acute kidney injury (AKI). Transcriptome analysis revealed coupling of FtH deficiency in monocytes and MΦ with ferroptosis activation, a regulated cell death associated with iron accumulation. Moreover, myeloid FtH deletion worsened AKI, increasing leukocyte infiltration and iron deposition, together with ferroptosis‐associated gene induction, oxidative stress, and lipid peroxidation. Notably, ⍺-synuclein (SNCA), an iron-binding protein and the main pathological driver of Parkinson’s disease, was robustly induced by both FtH deficiency and following AKI. Mechanistic studies showed that monomeric SNCA exhibits ferrireductase activity, amplifying redox cycling and promoting ferroptotic cell death. Furthermore, SNCA expression was elevated in kidney pathologies characterized by leukocyte expansion in both mouse models and human cohorts, suggesting that inflammatory microenvironments promote SNCA accumulation and redox imbalance. These findings define a MΦ FtH-SNCA regulatory axis as a key driver of ferroptosis in AKI, implicating SNCA as a pathological nexus between iron dyshomeostasis and inflammatory kidney injury.
Tanima Chatterjee, Sarah Machado, Kellen Cowen, Mary E. Miller, Bronte Johnson, Yanfeng Zhang, Laura A. Volpicelli-Daley, Lauren A. Fielding, Rudradip Pattanayak, Frida Rosenblum, László Potor, György Balla, Jozsef Balla, Christian Faul, Abolfazl Zarjou
Moderate hyperoxia (30–60% O₂) in premature infants promotes bronchial airway hyperresponsiveness (AHR) via airway smooth muscle (ASM), a key regulator of bronchoconstriction, bronchodilation, and remodeling. Understanding how O2 exposure drives long-term bronchial changes in prematurity is critical for developing therapies for airway disease across the lifespan. Premature lungs have immature antioxidant defenses, potentially due to disrupted mitochondrial dynamics, increasing susceptibility to O2-induced oxidative stress. Thus, mitochondrial homeostasis is highly relevant to ASM dysfunction and airway disease. We propose that hyperoxia in prematurity promotes mitochondrial dysfunction, and that the gasotransmitter hydrogen sulfide (H₂S) mitigates O2-induced mitochondrial damage in developing ASM. Human fetal ASM (fASM) were exposed to moderate hyperoxia to investigate the effects of exogenous H₂S donors (GYY4137, AP39) and stabilization of cystathionine β-synthase (CBS), an H₂S biosynthetic enzyme, on mitochondrial structure and function. Hyperoxia impaired fASM mitochondrial integrity, while H₂S donors in particular, or CBS stabilization attenuated adverse O2 effects on mitochondrial morphology, reactive oxygen species, respiration, calcium regulation, and contractility. These findings highlight the therapeutic potential of H₂S in the premature lung exposed to moderate hyperoxia.
Colleen M. Bartman, Michael Thompson, Samantha K. Hamrick, Niyati A. Borkar, Daniel Pfeffer-Kleemann, Preetham Ravi, Marta Schiliro, Yak Nak, Christian Vivar Ramon, Li Drake, Y. S. Prakash, Christina Pabelick
Heterogeneity in disease severity and treatment response in inflammatory bowel disease (IBD) likely evolve from individual differences in host-microbiota-immune interactions. Histological evaluation of intestinal biopsies is central to diagnosis, but histological parameters that define underlying immune mechanisms are limited. We investigated histological features that distinguish individual patient immune profiles in therapy-naive paediatric IBD patients (age 6‒18-years-old) using biopsy immunohistochemistry and transcriptomics and plasma proteomics across two cohorts. High colonic epithelial expression of Secretory Leukocyte Protease Inhibitor (SLPI), a microbiota-induced regulator of epithelial function, occurred in IBD patients with high clinical disease activity and more severe endoscopic and microscopic disease activity. SLPI expression related to increased neutrophil infiltration, transcriptomic signatures of activation and genes known to associate with therapeutic resistance. High SLPI co-localized with high densities of IL-17-secreting cells and was associated with high plasma concentrations of Th17-related immune proteins. Additionally, patients with high intestinal SLPI had an intrinsically different immunotype, in which circulating neutrophils exhibited altered transcription of genes involved in neutrophil granule formation, phagocytosis, oxidative phosphorylation, and interferon signalling. Thus, high colonic SLPI expression at diagnosis associates with severe IBD, increased IL-17A-neutrophil pathway responses and altered transcriptomic wiring of circulating neutrophils.
Sandrine Nugteren, Beatriz Calado, Ytje Simons-Oosterhuis, Daniëlle H. Hulleman-van Haaften, Willem K. Smits, Renz C.W. Klomberg, Bastiaan Tuk, Mohammed Charrout, Dicky J. Lindenbergh-Kortleve, Michail Doukas, Mathijs A. Sanders, Gregory van Beek, Johanna C. Escher, Lissy de Ridder, Maria Fernanda Pascutti, Janneke N. Samsom
Viral lower respiratory tract infections are common early in life and are associated with long-term development of asthma, a chronic condition defined by reversible airflow obstruction secondary to inflammation. Understanding the immunologic mechanism connecting these two pathologies observed early in life becomes imperative to guide therapeutic measures. To investigate this connection, neonatal (day of life 4-6) or adult mice were infected with human metapneumovirus (HMPV) followed by a secondary HMPV infection 6 weeks later. Mice initially infected as neonates demonstrate increased mucus production, eosinophil recruitment, airway hyperresponsiveness, and Th2 T-cell differentiation following re-challenge compared to adult mice rechallenged with HMPV. Neonatal HMPV infection led to formation of Th2 clonally expanded tissue resident memory (TRM) T cells that were absent after adult HMPV. FTY720-mediated disruption of lymphocyte circulation demonstrated TRMs contribute to pathology. Local depletion of lung CD4+ T cells and JAK2-inhibition mitigated pathology. These findings suggest TRMs uniquely generated after early life viral infection can contribute to Th2-driven asthma pathology.
Emma E. Brown, Jie Lan, Olivia B. Parks, Li Fan, Dequan Lou, Alysia McCray, Lisa Mathews, Alexander J. Wardropper, Anna Shull, Michelle L. Manni, Hēth R. Turnquist, Kong Chen, Taylor Eddens
Metabolic dysfunction-associated steatotic liver disease (MASLD) is a global health concern with limited interventions. While the role of gut bacteria in MASLD has been extensively studied, the contribution of gut fungi remains largely unexplored. This study investigates the impact of fungal dysbiosis and the role of CARD9, a key adaptor protein in fungal sensing on gut-liver axis dysfunction in MASLD. Patients with advanced liver fibrosis exhibited distinct mycobiota profiles. Using a CARD9-deficient mouse model subjected to high-fat high-glucose/fructose feeding, we observed exacerbated liver injury and fibrosis accompanied by fungal dysbiosis, paralleling our findings in human patients. Beyond its established expression in myeloid cells, CARD9 was also detected in intestinal enterocytes where its expression was diminished under metabolic stress. Intestinal organoids with CARD9 inhibition had reduced expression of antimicrobial Reg3g, the tight junction protein ZO-1, and the antifungal enteroendocrine hormone PYY. These findings suggest that CARD9 maintains gut barrier integrity, preventing microbial translocation and subsequent liver injury and fibrosis. Our results provide new insights into the interplay between fungal dysbiosis, gut barrier dysfunction, and MASLD, and identify CARD9 as a key protein within this axis.
Vijay Pandyarajan, So Yeon Kim, Takashi Tsuchiya, Selena Liu, Sadam H. Bhat, Jieun Kim, David M. Underhill, Mazen Noureddin, Shelly C. Lu, Ekihiro Seki
BACKGROUND. High-dose influenza vaccine, containing four times more antigen than standard-dose, is recommended for people aged ≥ 65 years, but there is a knowledge gap surrounding its effect in people with HIV (PWH), who remain more vulnerable to serious influenza infections than people without HIV (PWoH) despite virological suppression. The primary goal of this study was to assess whether high-dose improves antibody responses in PWH, with a particular focus on older PWH. METHODS. We conducted a study to assess antibody responses to sequential high- versus standard-dose influenza vaccination in PWH. Young (18-40 years) PWoH (n=55) and PWH (n=37); and older (≥ 60 years) PWoH (n=72) and PWH (n=67) received standard-dose during the 2020-2024 seasons and 123 participants, including 41 older PWH, received high-dose the consecutive season. All PWH were virologically suppressed on ART. Hemagglutination inhibition (HAI) titer and HA-specific IgG were analyzed at 0- to 180-days post-vaccination (dpv); T cell activation-induced responses were assessed by flow cytometry. RESULTS. All groups mounted significant HAI and IgG responses to all vaccine antigens at 28 dpv, after standard- and high-dose vaccination. Responses to A/H1N1 were lower in magnitude and durability in older PWH compared to young PWoH following standard-dose and were not boosted with high-dose, whereas high-dose enhanced A/H3N2 and B/Victoria IgG, and CD4+ T cell responses to all antigens, in older PWH. CONCLUSION. Our data demonstrate partial efficacy of high-dose in augmenting antibody responses of older PWH while highlighting limitations in boosting A/H1N1-specific responses. TRIAL REGISTRATION. ClinicalTrials.gov NCT04487041. FUNDING. NIH grant (5R01AG068110).
Jonah Kupritz, Sheldon Davis, TianHao Liu, Prabhsimran Singh, Daniel Andrés Díaz–Pachón, Allan Rodriguez, Scott D. Boyd, Rajendra Pahwa, Suresh Pallikkuth, Savita G. Pahwa
Aberrant neutrophil (PMN) accumulation in the tissue induces chronic vascular diseases. Endothelial cells (ECs) regulate the access of PMNs into the tissue from the blood. However, the mechanisms that prevent PMNs from being activated and accumulating in the tissue, a hallmark of acute lung injury (ALI), remain elusive. We demonstrate that conditional deletion of Erg in ECs spontaneously alters the PMN transcriptome, which is enriched with genes that induce PMN recruitment, adhesion, activation, and 'do not eat me' signals due to impaired synthesis of the deubiquitinase, A20. Decreased A20 levels, in turn, activated the transcription factor NFκB and the secretion of MIP2α (human homolog of IL8) in ECs. EC-secreted MIP2α/IL8 engaged the CXCR2 cascade on PMNs, leading to their activation and inflammatory injury. These findings were recapitulated in the lungs and blood of PMNs from patients dying of ALI. Overexpression of the A20 gene in EC or pharmacological inhibition of CXCR2 on PMNs in iEC-Erg–/– mice rescued EC control of PMNs and tissue homeostasis, and enhanced mouse survival after pneumonia. Thus, the EC-Erg-A20 axis regulates PMN accumulation and hyperactivation in the lungs by inhibiting EC-mediated IL-8 activation of PMN-CXCR2, thereby providing a potential target for neutrophilic inflammatory vascular diseases.
Vigneshwaran Vellingiri, Vijay Avin Balaji Ragunathrao, Jagdish Chandra Joshi, Md Zahid Akhter, Mumtaz Anwar, Somenath Banerjee, Sayanti Datta, Viktor Pinneker, Steven M. Dudek, Yoshikazu Tsukasaki, Sandra Pinho, Dolly Mehta
Immune checkpoint inhibitors (ICIs) can cause immune-related adverse events (irAEs), with acute interstitial nephritis (ICI-AIN) being the most common irAE. While the exact mechanism remains unclear, upregulation of interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) pathways has been implicated. This study used a humanized chimeric PD-1/PD-L1 mouse model to assess renal effects of ICIs, alone or combined with pro-inflammatory cytokines, and to test if selective TNF-α blockade could prevent ICI-AIN. Mice were randomly divided into four experimental groups: Control, ICI-Only, ICI-Cytokines (ICI-Cyt), and ICI-Block (ICI-TNF-α blockade). Renal function and cytokine profiles were assessed, while kidney tissue was analyzed using microscopy and single-cell RNA sequencing. Histology revealed increased renal infiltration of CD4⁺/CD8⁺ T cells in ICI-treated groups and decreased TNF-α expression following TNF-α blockade. Additionally, kidney tissue ELISA demonstrated reduced IFN-γ levels following TNF-α blockade. Plasma IL-6, MCP-1, and TNF-α were lower in ICI-Block mice. Single-cell RNA sequencing revealed shifts in immune cell populations and genes of interest including: Bcl2a1, Icos, Il18r1, Ccr2, and Jaml. This humanized model replicates ICI-AIN key features, revealing a synergistic role of ICIs and pro-inflammatory cytokines. TNF-α blockade demonstrated protective effects, supporting its potential role in mitigating the risk of ICI-AIN.
Victor D. Cuenca Narvaez, Coraima Nava Chavez, Omar Al Refai, Johanna E. J. Jacobs, Luis E. Gutierrez, Song Zhang, Xiaoyan Li, Jacob B. Hirdler, Michael F. Romero, Joerg Herrmann, Xiaogang Li, Haidong Dong, Alfonso Eirin, Sandra M. Herrmann
This study provides a comprehensive evaluation of the cutaneous adipose tissue (CAT) transcriptome in psoriasis patients and investigates the effects of IL-17 blockade on CAT inflammation through a randomized placebo-controlled trial using secukinumab (ObePso-S study, NCT03055494). RNA sequencing analysis of CAT biopsies from 82 psoriasis patients revealed 2132 differentially expressed transcripts compared to healthy controls. Notably, significant gene dysregulation was observed in both lesional skin (LS)- and non-lesional (NL)-CAT, including activation of IL-17-driven pathways, antimicrobial peptide-related, and neutrophil degranulation signatures. Stratification by obesity demonstrated that obese psoriatic CAT exhibited more than 2-fold higher number of differentially expressed genes than non-obese counterparts, suggesting a synergistic interaction between psoriasis and obesity in driving CAT inflammation. Treatment with secukinumab markedly improved inflammatory signatures in psoriatic CAT, with greater improvements observed in obese patients. These findings reveal a pronounced and partially dependent on IL-17-dependent inflammatory phenotype in psoriatic CAT, challenge the conventional concept of psoriasis as a solely superficial skin disease, and highlight CAT as an important contributor to systemic inflammation in psoriasis.
Naomi Shishido-Takahashi, Sandra Garcet, Inna Cueto, Hong Beom Hur, Elisa F. Muscianisi, Jennifer Steadman, Andrew Blauvelt, James G. Krueger
GLP-1 receptor (GLP-1R) agonists decrease blood glucose and body weight and reduce rates of cardiovascular and renal disease. Although GLP-1R activation lowers blood pressure (BP), the underlying mechanisms remain incompletely understood and have been attributed to weight loss and endothelial cell GLP-1R signaling. Here, we show that GLP-1Rs in vascular smooth muscle cells (VSMCs) are essential for semaglutide-mediated BP reduction in mice. In contrast, GLP-1Rs in Tie2+ endothelial or immune cells are not required for semaglutide to lower BP. The VSMC GLP-1R is dispensable for the effects of semaglutide on food intake, body weight, and blood glucose, but is required for its actions to increase glomerular filtration rate and promote natriuresis. Systemic semaglutide administration resulted in proteomic changes in the renal artery and kidney in pathways related to platelet aggregation, fibrin clot formation, lipid metabolism, and pro-apoptotic signaling that are abolished in mice lacking VSMC GLP-1R expression. Moreover, semaglutide directly induced vasorelaxation in pre-constricted mesenteric arteries ex vivo. Together, these findings identify VSMCs as a key cellular target linking GLP-1R activation to BP regulation, renal electrolyte excretion, and proteomic changes in renal artery and kidney.
Kyle D. Medak, Jacqueline A. Koehler, Laurie L. Baggio, Maria J. Gonzalez-Rellan, Chi Kin Wong, Xiemin Cao, Vivikta Rao, Sean Kao, Yu Cui, Jiayi Fu, Easton Liaw, M. Golam Kabir, Jie Zhang, Jin Wei, Daniel J. Drucker
Insulin and glucagon are described to have opposing actions on hepatic glycogen metabolism. However, here we showed that their coordinated action promoted glycogen turnover and meal glucose storage. In mice, pharmacological doses of insulin or glucagon failed to alter hepatic glycogen, but the combination produced a robust decrease in glycogen content. Additivity between insulin and glucagon was also seen with the activation of hepatic insulin signaling intermediates. This signaling pathway drove glycogen synthesis, suggesting concurrent actions on glycogen breakdown and repletion. A mixed nutrient meal, which stimulates an increase in both insulin and glucagon, enhanced the incorporation of dietary glucose into hepatic glycogen. This was much more pronounced than the effects of glucose alone, which only stimulated insulin secretion. These findings revealed that glucagon is required for efficient hepatic glucose storage when acting in concert with insulin. Coordinated insulin-glucagon signaling thus emerged as a critical mechanism for hepatic glycogen cycling, challenging the classical paradigm that these hormones work in opposition.
Nidhi Kejriwal, David Bouslov, Cheyenne R. Castle, Riya S. Karve, Galina A. Arkharova, Ashot Sargsyan, Daniel J. Drucker, Guo-Fang Zhang, David A. D'Alessio, Jonathan E. Campbell, Megan E. Capozzi