Immunology
Abstract
BACKGROUND. Bacterial vaginosis (BV) causes genital inflammation and increases HIV risk, while a vaginal microbiota dominated by Lactobacillus species is associated with immune quiescence and relative HIV protection. BV treatment reduces genital inflammation, but it is unclear whether this is driven by a decrease in BV-associated bacteria or an increase in Lactobacillus. METHODS. To evaluate the short-term impact of standard BV treatment on genital immunology and the vaginal microbiota, vaginal swabs were collected immediately before and after metronidazole treatment for BV and analyzed with multiplex ELISA, metagenomic sequencing, and quantitative polymerase chain reaction. RESULTS. Topical metronidazole treatment rapidly reduced vaginal levels of proinflammatory cytokines, chemokines, and soluble immune markers of epithelial barrier disruption. Although the vaginal microbiota shifted to dominance by L. iners or L. jensenii, this proportional shift was primarily driven by a 2-4 log10 fold reduction in BV-associated bacteria absolute abundance; BV treatment induced no change in the absolute abundance of L. crispatus or L. iners, and only minor (<1 log10 fold) increases in L. gasseri and L. jensenii that were not independently associated with reduced inflammation in multivariable models. CONCLUSION. The genital immune benefits that are associated with Lactobacillus dominance following BV treatment were not directly attributable to an absolute increase in lactobacilli, but rather to the loss of BV-associated bacteria. TRAIL REGISTRATION. Participants were recruited as part of a randomized controlled trial (NCT02766023) from 2016 to 2020. FUNDING. Canadian Institutes of Health Research (PJT-156123) and the National Institute of Allergy and Infectious Diseases (HHSN2722013000141 and HHSN27200007).
Authors
Eric Armstrong, Anke Hemmerling, Steve Miller, Kerianne E. Burke, Sara J. Newmann, Sheldon R. Morris, Hilary Reno, Sanja Huibner, Maria Kulikova, Rachel Liu, Emily D. Crawford, Gloria R. Castañeda, Nico Nagelkerke, Bryan Coburn, Craig R. Cohen, Rupert Kaul
Abstract
PD-1 signaling on T cells is the major pathway that limits T cell immunity, but the efficacy of anti–PD-1 therapy has been limited to a small proportion of patients with advanced cancers. We fortuitously observed that anti–PD-1 therapy depends on IL-2 signaling, which raises the possibility that a lack of IL-2 limits anti–PD-1–induced effector T cell expansion. To selectively deliver IL-2 to PD-1+CD8+ tumor-infiltrating lymphocytes (TILs), we engineered a low-affinity IL-2 paired with anti–PD-1 (PD-1–laIL-2), which reduced affinity to peripheral Treg cells but enhanced avidity to PD-1+CD8+ TILs. PD-1–laIL-2 exerted better tumor control and lower toxicity than single or mixed treatments. Mechanistically, PD-1–laIL-2 could effectively expand dysfunctional and tumor-specific CD8+ T cells. Furthermore, we discovered that presumably dysfunctional PD-1+TIM3+ TILs are the dominant tumor-specific T cells responding to PD-1–laIL-2. Collectively, these results highlight that PD-1–laIL-2 can target and reactivate tumor-specific TILs for tumor regression as a unique strategy with stronger efficacy and lower toxicity.
Authors
Zhenhua Ren, Anli Zhang, Zhichen Sun, Yong Liang, Jianfeng Ye, Jian Qiao, Bo Li, Yang-Xin Fu
Abstract
Anti-TNF antibodies are effective for treating patients with inflammatory bowel disease (IBD), but many patients fail to respond to anti-TNF therapy, highlighting the importance of TNF-independent disease. We previously demonstrated that acute deletion of two IBD susceptibility genes, A20 (Tnfaip3) and Abin-1 (Tnip1), in intestinal epithelial cells (IECs) sensitized mice to both TNF-dependent and TNF-independent death. Here we show that TNF-independent IEC death after A20 and Abin-1 deletion was rescued by germ-free derivation or deletion of MyD88, while deletion of Trif provided only partial protection. Combined deletion of Ripk3 and Casp8, which inhibits both apoptotic and necroptotic death, completely protected against death after acute deletion of A20 and Abin-1 in IECs. A20 and Abin-1-deficient IECs were sensitized to TNF-independent, TNFR-1-mediated death in response to lymphotoxin alpha (LT⍺) homotrimers. Blockade of LT⍺ in vivo reduced weight loss and improved survival when combined with partial deletion of MyD88. Biopsies of inflamed colon mucosa from patients with IBD exhibited increased LTA and IL1B expression, including a subset of patients with active colitis on anti-TNF therapy. These data show that microbial signals, MyD88, and LT⍺ all contribute to TNF-independent intestinal injury.
Authors
Iulia Rusu, Elvira Mennillo, Jared L. Bain, Zhongmei Li, Xiaofei Sun, Kimberly M. Ly, Yenny Y. Rosli, Mohammad Naser, Zunqiu Wang, Rommel Advincula, Philip Achacoso, Ling Shao, Bahram Razani, Ophir D. Klein, Alexander Marson, Jessie A. Turnbaugh, Peter J. Turnbaugh, Barbara A. Malynn, Averil Ma, Michael G. Kattah
Abstract
T cell polyfunctionality is a hallmark of protective immunity against pathogens and cancer, yet the molecular mechanism governing it remains mostly elusive. We found that canonical Wnt agonists inhibited human memory CD8+ T cell differentiation while simultaneously promoting the generation of highly polyfunctional cells. Downstream effects of Wnt activation persisted after removal of the drug, and T cells remained polyfunctional following subsequent cell division, indicating the effect is epigenetically regulated. Wnt activation induced a gene expression pattern that is enriched with stem cell–specific gene signatures and upregulation of protein arginine methyltransferase 1 (PRMT1), a known epigenetic regulator. PRMT1+CD8+ T cells are associated with enhanced polyfunctionality, especially the ability to produce IL-2. In contrast, inhibition of PRMT1 ameliorated the effects of Wnt on polyfunctionality. Chromatin immunoprecipitation revealed that H4R3me2a, a permissive transcription marker mediated by PRMT1, increased at the IL-2 promoter loci following Wnt activation. In vivo, Wnt-treated T cells exhibited superior polyfunctionality and persistence. When applied to cytomegalovirus (CMV) donor–seropositive, recipient-seronegative patients (D+/R–) lung transplant patient samples, Wnt activation enhanced CMV-specific T cell polyfunctionality, which is important in controlling CMV diseases. These findings reveal a molecular mechanism governing T cell polyfunctionality and identify PRMT1 as a potential target for T cell immunotherapy.
Authors
Bo-Yi Sung, Yi-Hsin Lin, Qiongman Kong, Pali D. Shah, Joan Glick Bieler, Scott Palmer, Kent J. Weinhold, Hong-Ru Chang, Hailiang Huang, Robin K. Avery, Jonathan Schneck, Yen-Ling Chiu
Abstract
BACKGROUND The temporal clustering of a cancer diagnosis with dermatomyositis (DM) onset is strikingly associated with autoantibodies against transcriptional intermediary factor 1-γ (TIF1-γ). Nevertheless, many patients with anti–TIF1-γ antibodies never develop cancer. We investigated whether additional autoantibodies are found in anti–TIF1-γ–positive patients without cancer.METHODS Using a proteomic approach, we defined 10 previously undescribed autoantibody specificities in 5 index anti–TIF1-γ–positive DM patients without cancer. These were subsequently examined in discovery (n = 110) and validation (n = 142) cohorts of DM patients with anti–TIF1-γ autoantibodies.RESULTS We identified 10 potentially novel autoantibodies in anti–TIF1-γ–positive DM patients, 6 with frequencies ranging from 3% to 32% in 2 independent DM cohorts. Autoantibodies recognizing cell division cycle and apoptosis regulator protein 1 (CCAR1) were the most frequent, and were significantly negatively associated with contemporaneous cancer (discovery cohort OR 0.27 [95% CI 0.7–1.00], P = 0.050; validation cohort OR 0.13 [95% CI 0.03–0.59], P = 0.008). When cancer did emerge, it occurred significantly later in anti-CCAR1–positive compared with anti-CCAR1–negative patients (median time from DM onset 4.3 vs. 0.85 years, respectively; P = 0.006). Cancers that emerged were more likely to be localized (89% of anti-CCAR1–positive cancers presenting at stage 0 or 1 compared with 42% of patients without anti-CCAR1 antibodies, P = 0.02). As the number of additional autoantibody specificities increased in anti–TIF1-γ–positive DM patients, the frequency of cancer decreased (P < 0.001).CONCLUSION As the diversity of immune responses in anti–TIF1-γ DM patients increases, the likelihood of cancer emerging decreases. Our findings have important relevance for cancer risk stratification in DM patients and for understanding natural immune regulation of cancer in humans.TRIAL REGISTRATION Not applicable.FUNDING SOURCES The NIH, the Donald B. and Dorothy L. Stabler Foundation, and the Huayi and Siuling Zhang Discovery Fund.
Authors
David F. Fiorentino, Christopher A. Mecoli, Matthew C. Rosen, Lorinda S. Chung, Lisa Christopher-Stine, Antony Rosen, Livia Casciola-Rosen
Abstract
We investigated the interplay between genetics and oral peanut protein exposure in the determination of the immunological response to peanut using the targeted intervention in the LEAP clinical trial. We identified an association between peanut-specific IgG4 and HLA-DQA1*01:02 that was only observed in the presence of sustained oral peanut protein exposure. The association between IgG4 and HLA-DQA1*01:02 was driven by IgG4 specific for the Ara h 2 component. Once peanut consumption ceased, the association between IgG4-specific Ara h 2 and HLA-DQA1*01:02 was attenuated. The association was validated by observing expanded IgG4-specific epitopes in people who carried HLA-DQA1*01:02. Notably, we confirmed the previously reported associations with HLA-DQA1*01:02 and peanut allergy risk in the absence of oral peanut protein exposure. Interaction between HLA and presence or absence of exposure to peanut in an allergen- and epitope-specific manner implicates a mechanism of antigen recognition that is fundamental to driving immune responses related to allergy risk or protection.
Authors
Kanika Kanchan, Stepan Grinek, Henry T. Bahnson, Ingo Ruczinski, Gautam Shankar, David Larson, George Du Toit, Kathleen C. Barnes, Hugh A. Sampson, Mayte Suarez-Farinas, Gideon Lack, Gerald T. Nepom, Karen Cerosaletti, Rasika A. Mathias
Abstract
BACKGROUND MEK inhibitors have limited activity in biliary tract cancers (BTCs) as monotherapy but are hypothesized to enhance responses to programmed death ligand 1 (PD-L1) inhibition.METHODS This open-label phase II study randomized patients with BTC to atezolizumab (anti–PD-L1) as monotherapy or in combination with cobimetinib (MEK inhibitor). Eligible patients had unresectable BTC with 1 to 2 lines of prior therapy in the metastatic setting, measurable disease, and Eastern Cooperative Oncology Group (ECOG) performance status less than or equal to 1. The primary endpoint was progression-free survival (PFS).RESULTS Seventy-seven patients were randomized and received study therapy. The trial met its primary endpoint, with a median PFS of 3.65 months in the combination arm versus 1.87 months in the monotherapy arm (HR 0.58, 90% CI 0.35–0.93, 1-tail P = 0.027). One patient in the combination arm (3.3%) and 1 patient in the monotherapy arm (2.8%) had a partial response. Combination therapy was associated with more rash, gastrointestinal events, CPK elevations, and thrombocytopenia. Exploratory analysis of tumor biopsies revealed enhanced expression of antigen processing and presentation genes and an increase in CD8/FoxP3 ratios with combination treatment. Patients with higher baseline or lower fold changes in expression of certain inhibitory ligands (LAG3, BTLA, VISTA) on circulating T cells had evidence of greater clinical benefit from the combination.CONCLUSION The combination of atezolizumab plus cobimetinib prolonged PFS as compared with atezolizumab monotherapy, but the low response rate in both arms highlights the immune-resistant nature of BTCs.TRIAL REGISTRATION ClinicalTrials.gov NCT03201458.FUNDING National Cancer Institute (NCI) Experimental Therapeutics Clinical Trials Network (ETCTN); F. Hoffmann-La Roche, Ltd.; NCI, NIH (R01 CA228414-01 and UM1CA186691); NCI’s Specialized Program of Research Excellence (SPORE) in Gastrointestinal Cancers (P50 CA062924); NIH Center Core Grant (P30 CA006973); and the Passano Foundation.
Authors
Mark Yarchoan, Leslie Cope, Amanda N. Ruggieri, Robert A. Anders, Anne M. Noonan, Laura W. Goff, Lipika Goyal, Jill Lacy, Daneng Li, Anuj K. Patel, Aiwu R. He, Ghassan K. Abou-Alfa, Kristen Spencer, Edward J. Kim, S. Lindsey Davis, Autumn J. McRee, Paul R. Kunk, Subir Goyal, Yuan Liu, Lauren Dennison, Stephanie Xavier, Aditya A. Mohan, Qingfeng Zhu, Andrea Wang-Gillam, Andrew Poklepovic, Helen X. Chen, Elad Sharon, Gregory B. Lesinski, Nilofer S. Azad
Abstract
Authors
Rory D. de Vries, Marieke van der Heiden, Daryl Geers, Celine Imhof, Debbie van Baarle, RECOVAC-IR Collaborators
Abstract
It has been revealed that 2’3’-cyclic-GMP-AMP (cGAMP), a second messenger that activates the antiviral stimulator of interferon genes (STING), elicits an antitumoral immune response. Since cGAMP cannot cross the cell membrane, it is not clear how intracellular STING has been activated by extracellular cGAMP until SLC19A1 was identified as an importer to transport extracellular cGAMP into cytosol. However, SLC19A1 deficient cells also sense extracellular cGAMP, suggesting the presence of mechanisms other than the facilitating transporters for STING sensing extracellular cGAMP. Here, we identified an alternatively spliced STING isoform (plasmatic membrane STING, pmSTING) that localized in the plasma membrane with its C-terminus outside the cell, due to lack of one transmembrane domain in its N-terminus compared to canonical STING, by using immunoprecipitation, immunofluorescence and flow cytometry. Further studies showed that extracellular cGAMP not only promoted the dimerization of pmSTING and interaction of pmSTING with Tank-binding kinase 1 (TBK1) and interferon regulatory factor 3 (IRF3), but also enhanced the phosphorylation of TBK1 and IRF3 and production of interferon in pmSTING transfected cells. Additionally, we also identified similar pmSTING isoforms in other animal species including human. This study suggests a conserved role for pmSTING in sensing extracellular cGAMP and provides insight into cGAMP’s role as an immunotransmitter.
Authors
Xiaobo Li, Yuanyuan Zhu, Xiao Zhang, Xiang An, Mingjiao Weng, Jiaqi Shi, Song Wang, Caiqi Liu, Shengnan Luo, Tongsen Zheng
Abstract
Repair of the infarcted heart requires TGF-β/Smad3 signaling in cardiac myofibroblasts. However, TGF-β-driven myofibroblast activation needs to be tightly regulated in order to prevent excessive fibrosis and adverse remodeling that may precipitate heart failure. We hypothesized that induction of the inhibitory Smad, Smad7 may restrain infarct myofibroblast activation, and we examined the molecular mechanisms of Smad7 actions. In a mouse model of non-reperfused infarction, Smad3 activation triggered Smad7 synthesis in α-SMA+ infarct myofibroblasts, but not in α-SMA-/PDGFRα+ fibroblasts. Myofibroblast-specific Smad7 loss increased heart failure-related mortality, worsened dysfunction, and accentuated fibrosis in the infarct border zone and in the papillary muscles. Smad7 attenuated myofibroblast activation and reduced synthesis of structural and matricellular extracellular matrix proteins. Smad7 actions on TGF-β cascades involved de-activation of Smad2/3 and non-Smad pathways, without any effects on TGF-β receptor activity. Unbiased transcriptomic and proteomic analysis identified receptor tyrosine kinase signaling as a major target of Smad7. Smad7 interacted with Erbb2 in a TGF-independent manner and restrained Erbb1/Erbb2 activation, suppressing fibroblast expression of fibrogenic proteases, integrins and CD44. Smad7 induction in myofibroblasts serves as an endogenous TGF-β-induced negative feedback mechanism that inhibits post-infarction fibrosis by restraining Smad-dependent and Smad-independent TGF-β responses, and by suppressing TGF-independent fibrogenic actions of Erbb2.
Authors
Claudio Humeres, Arti V. Shinde, Anis Hanna, Linda Alex, Silvia C. Hernandez, Ruoshui Li, Bijun Chen, Simon J. Conway, Nikolaos G. Frangogiannis
Copyright © 2022 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)