The HIV-1 proviral landscape reveals Nef contributes to HIV-1 persistence in effector memory CD4+ T-cells

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Abstract

Despite long-term antiretroviral therapy (ART), HIV-1 persists within a reservoir of CD4+ T-cells that contribute to viral rebound if treatment is interrupted. Identifying the cellular populations that contribute to the HIV-1 reservoir and understanding the mechanisms of viral persistence are necessary to achieve an effective cure. In this regard, through Full-Length Individual Proviral Sequencing, we observed that the HIV-1 proviral landscape was different and changed with time on ART across naïve and memory CD4+ T-cell subsets isolated from 24 participants. We found that the proportion of genetically-intact HIV-1 proviruses was higher and persisted over time in effector memory CD4+ T-cells when compared with naïve, central, and transitional memory CD4+ T-cells. Interestingly, we found that escape mutations remained stable over time within effector memory T-cells during therapy. Finally, we provided evidence that Nef plays a role in the persistence of genetically-intact HIV-1. These findings posit effector memory T-cells as a key component of the HIV-1 reservoir and suggest Nef as an attractive therapeutic target.

Authors

Gabriel Duette, Bonnie Hiener, Hannah Morgan, Fernando G. Mazur, Vennila Mathivanan, Bethany A. Horsburgh, Katie Fisher, Orion Tong, Eunok Lee, Haelee Ahn, Ansari Shaik, Rémi Fromentin, Rebecca Hoh, Charline Bacchus-Souffan, Najla Nasr, Anthony Cunningham, Peter W. Hunt, Nicolas Chomont, Stuart G. Turville, Steven G. Deeks, Anthony D. Kelleher, Timothy E. Schlub, Sarah Palmer

An Asian-specific variant in human IgG1 represses colorectal tumorigenesis by shaping the tumor microenvironment

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Abstract

Emerging studies have focused on ways to treat cancers by modulating T cell activation. However, whether B cell receptor signaling in the tumor microenvironment (TME) can be harnessed for immunotherapy is unclear. Here we reported that an Asian-specific variant of human IgG1 containing a Gly396 to Arg396 substitution (hIgG1-G396R) conferred improved survival of colorectal cancer (CRC) patients. Murine functional homolog mIgG2c-G400R knock-in mice recapitulated the alleviated tumorigenesis and progression in murine colon carcinoma models. Immune profiling of the TME revealed broad mobilizations of IgG1+ plasma cells, CD8+ T cells, CD103+ DCs and active tertiary lymphoid structure formation, suggesting effective anti-tumor microenvironment in hIgG1-G396R CRC patients. Mechanistically, this variant potentiated tumor-associated antigen (TAA)-specific plasma cell differentiation and thus antibody production. These elevated TAA-specific IgG2c antibodies in turn efficiently boosted the antibody-dependent tumor cell phagocytosis and TAA presentation to effector CD8+ T cells. Notably, adoptive transfer of TAA-specific class-switched memory B cells harboring this variant exhibited therapeutic efficacy in murine tumor models, indicating the clinical potential. All these results prompted a prospective investigation of hIgG1-G396R in CRC patients as a biomarker for clinical prognosis and demonstrated that manipulating the functionality of IgG1+ memory B cells in tumors could improve immunotherapy outcomes.

Authors

Bing Yang, Zhen Zhang, Xiangjun Chen, Xu-Yan Wang, Shishang Qin, Liaoqi Du, Changjiang Yang, Liyu Zhu, Wenbo Sun, Yongjie Zhu, Qinwen Zheng, Shidong Zhao, Quan Wang, Long Zhao, Yilin Lin, Jinghe Huang, Fan Wu, Lu Lu, Fei Wang, Wenjie Zheng, Xiao-Hua Zhou, Xiaozhen Zhao, Ziye Wang, Xiaolin Sun, Yingjiang Ye, Shan Wang, Zhanguo Li, Hai Qi, Zemin Zhang, Dong-Ming Kuang, Lei Zhang, Zhanlong Shen, Wanli Liu

ADAR1-mediated RNA editing links ganglioside catabolism to glioblastoma stem cell maintenance

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Abstract

Glioblastoma (GBM) is the most common and lethal primary malignant brain tumor, containing GBM stem cells (GSCs) that contribute to therapeutic resistance and relapse. Exposing potential GSC vulnerabilities may provide therapeutic strategies against GBM. Here, we interrogated the role of Adenosine-to-Inosine (A-to-I) RNA editing mediated by ADAR1 (adenosine deaminase acting on RNA 1) in GSCs and found that both ADAR1 and global RNA editomes were elevated in GSCs compared to normal neural stem cells (NSCs). ADAR1 inactivation or blocking the upstream JAK/STAT pathway through TYK2 inhibition impaired GSC self-renewal and stemness. Downstream of ADAR1, RNA editing of the 3’UTR of GM2A, a key ganglioside catabolism activator, proved to be critical, as interfering with ganglioside catabolism showed similar functional impact on GSCs as ADAR1 disruption. These findings reveal RNA editing links ganglioside catabolism to GSC self-renewal and stemness, exposing a potential vulnerability of GBM for therapeutic intervention.

Authors

Li Jiang, Yajing Hao, Changwei Shao, Qiulian Wu, Briana C. Prager, Ryan C. Gimple, Gabriele Sulli, Leo J.K. Kim, Guoxin Zhang, Zhixin Qiu, Zhe Zhu, Xiang-Dong Fu, Jeremy N. Rich

Targeting transforming growth factor- β (TGF-β) for treatment of osteogenesis imperfecta

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Abstract

BACKGROUND. Currently, there is no disease-specific therapy for osteogenesis imperfecta (OI). Preclinical studies have shown that excessive TGF-β signaling is a driver of pathogenesis in OI. Here, we evaluated TGF-β signaling in children with OI and translated this discovery by conducting a phase 1 clinical trial of TGF-β inhibition in adults with OI. METHODS. Histology and RNASeq were performed on bones obtained from children affected (n=10) and unaffected (n=4) by OI. Gene Ontology (GO) enrichment assay, gene set enrichment analysis (GSEA), and Ingenuity Pathway Analysis (IPA) were used to identify key dysregulated pathways. Reverse-phase protein array (RPPA), Western blot (WB), and Immunohistochemistry (IHC) were performed to evaluate changes at the protein level. A phase 1 study with a single administration of fresolimumab, a pan-anti-TGF-β neutralizing antibody, was conducted in 8 adults with OI. Safety and effects of fresolimumab on bone remodeling markers and lumbar spine areal bone mineral density (LS aBMD) were assessed. RESULTS. OI bone demonstrated woven structure, increased osteocyte density, high turnover, and reduced bone maturation. SMAD phosphorylation was the most significantly up-regulated GO molecular event. GSEA identified TGF-β pathway as top activated signaling pathway in OI. IPA showed that TGF-β was the most significant activated upstream regulator mediating the global changes identified in OI bone. Treatment with fresolimumab was well-tolerated and associated with increase in LS aBMD in participants with OI type IV, while those with more severe OI type III and VIII had unchanged or decreased LS aBMD. CONCLUSIONS. Our data confirm that TGF-β signaling is a driver pathogenic mechanism in OI bone and that anti-TGF-β therapy could be a potential disease-specific therapy with dose-dependent effects on bone mass and turnover. TRIAL REGISTRATION. NCT03064074 FUNDING. This work was supported by the Brittle Bone Disorders Consortium (BBDC) (U54AR068069). The BBDC is a part of the National Center for Advancing Translational Science’s (NCATS’) RDCRN. The BBDC is funded through a collaboration between the Office of Rare Disease Research (ORDR) of NCATS, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institute of Dental and Craniofacial Research (NIDCR), National Institute of Mental Health (NIMH) and National Institute of Child Health and Human Development (NICHD). The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH. The BBDC was also supported by the OI Foundation. The work was supported by The Clinical Translational Core of BCM IDDRC (P50HD103555) from the Eunice Kennedy Shriver NICHD. Funding from the USDA/ARS under Cooperative Agreement No. 58-6250-6-001 also facilitated analysis for the study procedures. The contents of this publication do not necessarily reflect the views or policies of the USDA, nor does mention of trade names, commercial products, or organizations imply endorsement by the US Government. The study was supported by a research agreement with Sanofi Genzyme.

Authors

I-Wen Song, Sandesh C.S. Nagamani, Dianne Nguyen, Ingo Grafe, Vernon Reid Sutton, Francis H. Gannon, Elda Munivez, Ming-Ming Jiang, Alyssa Tran, Maegen Wallace, Paul Esposito, Salma Musaad, Elizabeth Strudthoff, Sharon McGuire, Michele Thornton, Vinitha Shenava, Scott Rosenfeld, Roman Shypailo, Eric Orwoll, Brendan Lee

Lysosomal exocytosis of HSP70 stimulates monocytic BMP6 expression in Sjögren’s syndrome

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Abstract

BMP6 is a central cytokine in the induction of Sjögren's syndrome (SS)-associated secretory hypofunction. However, the upstream initiation leading to the production of this cytokine in SS is unknown. In this study, RNA in situ hybridization on salivary gland sections taken from SS patients indicated monocytic lineage cells as a cellular source of BMP6. RNA sequencing data from human salivary glands suggested TLR4 signaling was an upstream regulator of BMP6, which was confirmed by in vitro cell assays and single-cell transcriptomics of human PBMCs. Further investigation showed HSP70 was an endogenous natural TLR4 ligand that stimulated BMP6 expression in SS. Release of HSP70 from epithelial cells could be triggered by overexpression of lysosome-associated membrane protein 3 (LAMP3), a protein also associated with SS in several transcriptome studies. In vitro studies supported HSP70 was released as a result of lysosomal exocytosis initiated by LAMP3 expression, and reverse transcription PCR on RNA from minor salivary glands of SS patients confirmed a positive correlation between BMP6 and LAMP3 expression. BMP6 expression could be experimentally induced in mice by overexpression of LAMP3, which developed an SS-like phenotype. The newly identified LAMP3/HSP70/BMP6 axis provided an etiological model for SS gland dysfunction and autoimmunity.

Authors

Ying-Qian Mo, Hiroyuki Nakamura, Tsutomu Tanaka, Toshio Odani, Paola Perez, Youngmi Ji, Benjamin N. French, Thomas J.F. Pranzatelli, Drew G. Michael, Hongen Yin, Susan S. Chow, Maryam Khalaj, Sandra A. Afione, Changyu Zheng, Fabiola Reis Oliveira, Ana Carolina F. Motta, Alfredo Ribeiro-Silva, Eduardo M. Rocha, Cuong Q. Nguyen, Masayuki Noguchi, Tatsuya Atsumi, Blake M. Warner, John A. Chiorini

Arginine deprivation alters microglia polarity and synergises with radiation to eradicate non arginine auxotrophic glioblastoma tumors

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Abstract

New approaches for the management of glioblastoma (GBM) are an urgent and unmet clinical need. Here, we illustrate that the efficacy of radiotherapy for GBM is strikingly potentiated by concomitant therapy with the arginine depleting agent ADI-PEG20 in a non-arginine auxotrophic cellular background (Arginine Succinate Synthetase 1 positive). Moreover, this combination led to durable and complete radiological and pathological response with extended disease-free survival in an orthotopic immune competent model of GBM with no significant toxicity. ADI-PEG20 not only enhances the cellular sensitivity of Arginine succinate synthetase 1 positive GBM to ionising radiation by elevated production of nitric oxide (NO) and hence generation of cytotoxic peroxynitrites, but also promotes glioma-associated macrophages/microglia infiltration into tumors and turns their classical anti-inflammatory (pro-tumor) phenotype into a pro-inflammatory (anti-tumor) phenotype. Our results provide an effective, well-tolerated and simple strategy to improve GBM treatment which merits consideration for early evaluation in clinical trials.

Authors

Nabil Hajji, Juan Garcia-Revilla, Manuel Sarmiento Soto, Richard Perryman, Jake J. Symington, Chad C. Quarles, Deborah R. Healey, Yijie Guo, Manuel Luis Orta-Vázquez, Santiago Mateos-Cordero, Khalid Shah, John Bomalaski, Giulio Anichini, Andreas G. Tzakos, Timothy Crook, Kevin O'Neill, Adrienne C. Scheck, Jose Luis Venero, Nelofer Syed

Sortilin restricts secretion of apolipoprotein B-100 by hepatocytes under stressed but not basal conditions

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Abstract

Genetic variants at the SORT1 locus in humans causing increased SORT1 expression in liver are significantly associated with reduced plasma levels of LDL cholesterol and apolipoprotein B (apoB). However, the role of hepatic sortilin remains controversial, as genetic deletion of sortilin in mice has yielded variable and conflicting effects on apoB secretion. Sort1 knockout mice on a chow diet and several Sort1-deficient hepatocyte lines displayed no difference in apoB secretion. When these models were challenged with high fat or ER stress, the loss of Sort1 expression resulted in a significant increase in apoB-100 secretion. Sort1 overexpression studies yielded reciprocal results. Importantly, diabetic carriers of SORT1 variant have larger decreases in plasma apoB, TG, and VLDL and LDL particle number as compared to non-diabetics with the same variants. We conclude that under basal non-stressed conditions, loss of sortilin has little effect on hepatocyte apoB secretion, but that in the setting of lipid-loading or ER stress, sortilin deficiency leads to increased apoB secretion. These results are consistent with the directionality of effect in human genetics studies and suggest that under stress conditions, hepatic sortilin directs apoB toward lysosomal degradation rather than secretion, potentially serving as a quality control step in the apoB secretion pathway in hepatocytes.

Authors

Donna M. Conlon, Carolin V. Schneider, Yi-An Ko, Amrith Rodrigues, Kathy Guo, Nicholas J. Hand, Daniel J. Rader

Metronidazole treatment rapidly reduces genital inflammation through effects on bacterial vaginosis-associated bacteria rather than lactobacilli

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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

Targeting NANOG/HDAC1 axis reverses resistance to PD-1 blockade by reinvigorating anti-tumor immunity cycle

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Abstract

Immune checkpoint blockade (ICB) therapy has shifted the paradigm for cancer treatment. However, the majority of patients lack effective responses due to the emergence of immune-refractory tumors that disrupt the amplification of anti-tumor immunity. Therefore, identifying clinically available targets that restrict anti-tumor immunity is required to develop potential combination strategies. Here, using the transcriptome data of cancer patients treated with programmed cell death protein-1 (PD-1) therapy, and newly-established mouse preclinical anti-PD-1 therapy-refractory models, we identified NANOG as a novel factor restricting the amplification of anti-tumor immunity cycle, thereby contributing to the immune-refractory feature of the tumor microenvironment (TME). Mechanistically, NANOG induced insufficient T cell infiltration and resistance to CTL-mediated killing via the HDAC1-dependent regulation of CXCL10 and MCL1, respectively. Importantly, HDAC1 inhibition using an actionable agent sensitized NANOGhigh immune-refractory tumors to PD-1 blockade by reinvigorating the anti-tumor immunity cycle. Thus, our findings implicate the NANOG/HDAC1 axis as a central molecular target for controlling immune-refractory tumors and provide a rationale for combining HDAC inhibitors to reverse the refractoriness of tumors to ICB therapy.

Authors

Se Jin Oh, Hyo-Jung Lee, Kwon-Ho Song, Suyeon Kim, Eunho Cho, Jaeyoon Lee, Marcus W. Bosenberg, Tae Woo Kim

Hepatic FoxOs link insulin signaling with plasma lipoprotein metabolism through an apolipoprotein M/sphingosine-1-phosphate pathway

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Abstract

Multiple beneficial cardiovascular effects of HDL are dependent on sphingosine-1-phosphate (S1P). S1P associates with HDL by binding to apolipoprotein M (ApoM). Insulin resistance is a major driver of dyslipidemia and cardiovascular risk. However, the mechanisms linking alterations in insulin signaling with plasma lipoprotein metabolism are incompletely understood. The insulin-repressible FoxO transcription factors play a key role in mediating the effects of hepatic insulin action on glucose and lipoprotein metabolism. This work aims to determine whether hepatic insulin signaling regulates HDL-S1P, and the underlying molecular mechanisms.We report that insulin resistant, nondiabetic human subjects in two independent cohorts have decreased HDL-S1P levels, but no change in total plasma S1P. This also occurs in the mouse model of insulin resistance, db/db mice, which have low ApoM and a specific reduction of S1P in the HDL fraction, with no change in total plasma S1P. Using mice with hepatocyte deletion of the three insulin-repressible FoxO transcription factors (L-FoxO1,3,4), we found that hepatic FoxOs are required for ApoM expression and S1P association with HDL, without affecting total plasma S1P. In L-FoxO1,3,4 mice, total plasma S1P levels are similar to controls, but S1P is nearly absent from HDL, and is instead increased in the lipoprotein depleted plasma fraction. This phenotype is restored to normal by rescuing ApoM in L-FoxO1,3,4 mice. Our findings show that insulin resistance in humans and mice is associated with decreased HDL-associated S1P. Hepatic FoxO transcription factors are novel regulators of the ApoM-S1P pathway.

Authors

María Concepción Izquierdo, Niroshan Shanmugarajah, Samuel X. Lee, Michael J. Kraakman, Marit Westerterp, Takumi Kitamoto, Michael Harris, Joshua R. Cook, Galina A. Gusarova, Kendra Zhong, Elijah Marbuary, InSug O-Sullivan, Nikolaus F. Rasmus, Stefania Camastra, Terry G. Unterman, Ele Ferrannini, Barry E. Hurwitz, Rebecca A. Haeusler