Research
Abstract
Toll-like receptors (TLRs) are being explored to enhance immunity in HIV cure strategies. The TLR7 agonist GS-9620 promotes immune activation, reactivates latent HIV, and delays viral rebound in some people with HIV. Previous work has shown that biological sex influences TLR7 signaling. This study examined the interplay between biological sex, age, and the sex hormones 17β-estradiol, progesterone, and testosterone on GS-9620’s ability to promote cytokine secretion and activate CD4, CD8, and NK cells ex vivo. Interestingly, sex hormones had no effect on GS-9620-mediated immune activation or cytokine induction. However, we found that GS-9620 activity was influenced by age only in female donors. Further, we found that GS-9620-mediated CD4 T cell activation was positively correlated with the induction of IFN-γ and IL-12, while CD4 T cell activation and IL-12 production were negatively correlated with age. Additionally, CD8 T cell activation was positively correlated with IFN-γ production. Mechanistically, IFN-γ was sufficient to promote higher immune activation of both CD4 and CD8 T cells in female versus male donors. In conclusion, biological sex and age, but not sex hormones, influence GS-9620-mediated immune activation. Understanding these factors will help design and evaluate future clinical trials using GS-9620 for an HIV cure.
Authors
Carissa S. Holmberg, Callie Levinger, Adam R. Ward, Alberto Bosque
Abstract
Non-small cell lung cancer (NSCLC) largely consists of lung squamous (LUSC) and lung adenocarcinoma (LUAD). Alterations in the TRP53 and PTEN tumor suppressors are common in both subtypes, but their relationship with SOX2 is poorly understood. We deleted Trp53 or Pten in a C57BL/6J-Sox2hi;Nkx2-1-/-;Lkb1-/- (SNL) genetic background and generated a highly metastatic LUSC cell line (LN2A; derived from a Sox2hi mouse model, followed by Trp53, Pten, and Cdkn2a deletion). Histologic and single-cell RNAseq analyses corroborated that SNL mice developed mixed tumors with both LUAD and LUSC histopathology while SNL-Trp53 and SNL-Pten mice developed LUAD and LN2A tumors retained LUSC morphology. Compared with SNL mice, additional loss of Trp53 or Pten resulted in significantly reduced survival, increased tumor burden and altered tumor mucin composition. We identified a sub-cluster of CD38+ tumor-associated inflammatory monocytes in the LN2A model that significantly enriched for activation of the classical and alternative complement pathways. Complement Factor B (CFB) is associated with poor survival in LUSC patients, and we observed the LN2A model had significantly improved survival on a Cfb-/- background. Our findings demonstrate a cooperative role of Trp53 and Pten tumor suppressors in Sox2-mediated NSCLC tumor progression, mucin production, and remodeling of the immune tumor microenvironment.
Authors
Nisitha Sengottuvel, Kristina M. Whately, Jennifer L Modliszewski, Rani S. Sellers, William D. Green, Weida Gong, Allison T. Woods, Eric W. Livingston, Katerina D. Fagan-Solis, Gabrielle Cannon, Lincy Edatt, Hong Yuan, Aaron C. Chack, Yazmin Sanchez, Katherine Zhou, Alyaa Dawoud, Jarred M. Green, Virginia Godfrey, J Justin Milner, Gaorav P. Gupta, Chad V. Pecot
Abstract
Estrogen receptor alpha (ER) is a critical driver of tumorigenesis and tumor progression in most breast cancers. Endocrine therapies (ET) targeting ER are central to treating hormone receptor-positive breast cancer (BC), but resistance poses a clinical challenge. Some resistance mechanisms, particularly those involving estrogen-independent activity such as the ESR1 mutations, rely on ER signaling, supporting the need for next-generation ET. We investigated the preclinical efficacy of imlunestrant, an oral selective ER degrader, in ER-positive BC pre-clinical models, including models harboring the Y537S ESR1 mutation, an activating mutation. Imlunestrant demonstrated antagonistic activity and effective degradation of both wild-type and mutant ER, resulting in cell growth suppression. In vivo, imlunestrant outperformed fulvestrant leading to tumor regression in a patient derived xenograft harboring the Y537S ESR1 mutation. Cyclic mutiplexed immunofluorescence and transcriptomic analysis revealed enhanced cell cycle arrest and downregulation of estrogen-responsive genes with imlunestrant treatment. Additionally, a genome wide CRISPR knock-out screen identified several vulnerabilities that were either persistent or gained after imlunestrant treatment, providing a rationale for future studies of combination treatments with imlunestrant. Collectively, these results highlight the on-target and selective activity of imlunestrant, which can circumvent resistance engendered by the Y537S ESR1 mutation.
Authors
Shira Sherman, Zachary M. Sandusky, Douglas Russo, David Zak, Agostina Nardone, Delia Friel, Francisco Hermida-Prado, Capucine Heraud, Genevra Kuziel, Ana Verma, Giorgio Gaglia, Sheheryar Kabraji, Quang-De Nguyen, Sandro Santagata, Sean W. Fanning, Rinath Jeselsohn
Abstract
Measles remains one of the most important causes of worldwide morbidity and mortality in children. Measles virus (MeV) replicates extensively in lymphoid tissue and most deaths are due to other infectious diseases associated with MeV-induced loss of circulating antibodies to other pathogens. To determine whether remdesivir, a broad-spectrum direct-acting antiviral, affects MeV-induced loss of antibody to other pathogens, we expanded the VirScan technology to detect antibody to both human and macaque pathogens. We measured the antibody reactivity to MeV and non-MeV viral peptides using plasma from MeV-infected macaques that received remdesivir either as post-exposure prophylaxis (d3-14, PEP) or as late treatment (d11-22, LT) in comparison with macaques that were not treated. Remdesivir PEP, but not LT, limited the loss of antibody to non-MeV pathogens. Remdesivir PEP also limited the antibody response to MeV with a decrease in both the magnitude and breadth of the epitopes recognized. LT had little effect on the magnitude of the MeV-specific antibody response but affected the breadth of the response. Therefore, early, but not late, treatment of measles with the direct-acting antiviral remdesivir prevents the loss of antibody to other pathogens but decreases the response to MeV.
Authors
Andy Kwan Pui Chan, Liting Liu, William R. Morgenlander, Manjusha Thakar, Nadine A. Peart Akindele, Jacqueline Brockhurst, Shristi Ghimire, Maggie L. Bartlett, Kelly A. Metcalf Pate, Victor C. Chu, Meghan S. Vermillion, Danielle P. Porter, Tomas Cihlar, Michael J. Mina, H. Benjamin Larman, Diane E. Griffin
Abstract
Human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM) is a rare neurodegenerative disease with largely elusive molecular mechanisms, impeding targeted therapeutic advancements. This study aimed to identify the critical molecule responsible for neuronal damage in HAM, its source, and the regulatory mechanisms controlling its expression. Utilizing patient-derived cells and established cell lines, we discovered that HTLV-1 Tax, in conjunction with Specificity Protein 1 (Sp1), enhanced the expression of repulsive guidance molecule A (RGMa), a molecule known to contribute to neuronal damage. RGMa expression was specifically upregulated in HTLV-1-infected cells from HAM patients, particularly in those expressing HTLV-1 Tax. Furthermore, in CD4+ cells from HAM patients, the level of H3K27me3 methylation upstream of the RGMA gene locus was reduced, making RGMA more prone to constitutive expression. We demonstrated that HTLV-1-infected cells in HAM inflict neuronal damage via RGMa. Crucially, the neutralizing antibody against RGMa, unasnemab/MT-3921, effectively mitigated this damage in a dose-responsive manner, highlighting RGMa's pivotal role in neuronal damage and its potential as a therapeutic target for alleviating neuronal damage in HAM.
Authors
Natsumi Araya, Makoto Yamagishi, Makoto Nakashima, Naomi Asahara, Kazuhiro Kiyohara, Satoko Aratani, Naoko Yagishita, Erika Horibe, Izumi Ishizaki, Toshiki Watanabe, Tomoo Sato, Kaoru Uchimaru, Yoshihisa Yamano
Abstract
Overall survival (OS) in multiple myeloma (MM) varies between a couple of months to more than 20 years, influenced by tumor characteristics, the tumor microenvironment (TME), and patient factors such as age and frailty. We analyzed sequential BM samples from 45 MM patients with OS < 3 years versus > 8 years using mass cytometry and bulk TCRβ sequencing. Patients with long OS demonstrated stability in the TME and T cell environments, while those with short OS had significant changes at relapse, including fewer T cells, increased Treg cells, and more activated and exhausted CD8 T cells. Notably, higher PD-1 expression in CD8 T cells at diagnosis correlated with short OS. Additionally, short-OS patients exhibited a more monoclonal T cell environment at relapse, with abundance of hyperexpanded clones. These findings reveal distinct immune cell differences between patients with short and long OS.
Authors
Alenka Djarmila Behsen, Esten Nymoen Vandsemb, Tobias Schmidt Slørdahl, Karen Dybkær, Maja Zimmer Jakobsen, Muhammad Kashif, Johan Lund, Vincent Luong, Astrid Marta Olsnes, Anders Waage, Anne Marit Sponaas, Kristine Misund
Abstract
In the bullous autoimmune disease pemphigus vulgaris (PV), autoantibodies directed mainly against desmoglein (Dsg)1 and Dsg3 cause loss of desmosomal adhesion. We recently showed that intracellular cAMP increase by the phosphodiesterase 4 inhibitor apremilast was protective in different PV-models. Thus, we here analyzed the involvement of the cAMP effector exchange factor directly activated by cAMP (Epac)1. In Epac1-deficient mice pemphigus antibody-induced blistering was ameliorated in vivo while apremilast had no additional effect. Interestingly, augmented protein levels of Dsg1 and Dsg3 as well as increased Dsg1 mRNA levels and higher numbers of Dsg1- and Dsg3-dependent single molecule interactions were detected in keratinocytes derived from Epac1-deficient mice. This was paralleled by stronger intercellular adhesion under baseline conditions and prevention of pemphigus autoantibody-induced loss of intercellular adhesion. However, the protective effect of apremilast against loss of intercellular adhesion in response to the pathogenic Dsg3 antibody AK23 was attenuated in Epac1-deficient keratinocytes. Similarly, the Epac1 inhibitor Esi09 protected keratinocytes from pemphigus antibody-induced loss of adhesion. Mechanistically, Epac1 deficiency resulted in lack of apremilast-induced Rap1 activation and phosphorylation of Pg at S665. Taken together, these data indicate that Epac1 is involved in the regulation of baseline and cAMP-mediated stabilization of keratinocyte adhesion.
Authors
Anna M. Sigmund, Franziska C. Bayerbach, Daniela Kugelmann, Elisabeth Butz, Sina Moztarzadeh, Margarethe E.C. Schikora, Anja K.E. Horn, Mariya Y. Radeva, Sophia Engelmayer, Desalegn T. Egu, Matthias Goebeler, Enno Schmidt, Jens Waschke, Franziska Vielmuth
Abstract
Insulin secretion from pancreatic β-cells is initiated by membrane potential depolarization followed by activation of voltage-gated Ca2+ channels to trigger Ca2+-mediated insulin vesicle fusion with the β-cell plasma membrane. Here, we show that β-cell swelling associated with glucose metabolism is sensed by LRRC8 channel complexes and contributes to insulin secretion. Hypertonic perfusate (360–380 mOsm) dose-dependently impairs glucose-stimulated insulin secretion by counteracting β-cell swelling. Hypotonic perfusate alone, independent of glucose stimulation or KATP channel closure, is sufficient to increase β-cell intracellular Ca2+ and trigger insulin secretion. Inhibition of sodium-potassium-chloride cotransporter-1 with bumetanide, which diminishes the intracellular Cl– concentration in β-cells and consequently reduces Cl– efflux via LRRC8 channel complexes, also significantly reduces hypotonic-stimulated insulin secretion. Finally, stimulation of insulin secretion by the glucokinase activator GKA50, which is known to induce β-cell swelling, is entirely suppressed in β-cell-targeted Lrrc8a KO islets. These data support a model wherein the LRRC8 channel complex senses β-cell swelling triggered by glucose metabolism and regulates β-cell insulin secretion through activation of LRRC8-mediated Cl– efflux.
Authors
Tarek Mohamed Abd El-Aziz, Chen Kang, Litao Xie, John D. Tranter, Sumit Patel, Rahul Chadda, Maria S. Remedi, Rajan Sah
Abstract
While cytotoxic CD4+ tumor-infiltrating lymphocytes have anti-cancer activity in patients, whether these can be non-invasively monitored and how these are regulated remains obscure. By matching single cells with T cell receptors (TCR) in tumor and blood of bladder cancer patients, we identified distinct pools of tumor-matching cytotoxic CD4+ T cells in the periphery directly reflecting the predominant antigenic specificities of intratumoral CD4+ TILs. On one hand, the granzyme B (GZMB)-expressing cytotoxic CD4+ subset proliferated in blood in response to PD-1 blockade, but was separately regulated by the killer cell lectin-like receptor G1 (KLRG1) which inhibited their killing by interacting with E-cadherin. Conversely, a clonally related, granzyme K (GZMK)-expressing circulating CD4+ population demonstrated basal proliferation and a memory phenotype that may result from activation of GZMB+ cells, but was not directly mobilized by PD-1 blockade. As KLRG1 marked the majority of circulating tumor TCR-matched cytotoxic CD4+ T cells, this work nominates KLRG1 as a means to isolate them from blood and provide a window into intratumoral CD4+ recognition, as well as a putative regulatory receptor to mobilize the cytolytic GZMB+ subset for therapeutic benefit. Our findings also underscore ontogenic relationships of GZMB- and GZMK-expressing populations and the distinct cues that regulate their activity.
Authors
Serena S. Kwek, Hai Yang, Tony Li, Arielle Ilano, Eric D. Chow, Li Zhang, Hewitt Chang, Diamond Luong, Averey Lea, Matthew Clark, Alec Starzinski, Yimin Shi, Elizabeth McCarthy, Sima Porten, Maxwell V. Meng, Chun Jimmie Ye, Lawrence Fong, David Y. Oh
Abstract
Mutation studies of plasminogen activator inhibitor-1 (PAI-1) have previously implied that PAI-1 promotes lung fibrosis via a vitronectin (VTN) dependent mechanism. In the present study, employing two distinct murine fibrosis models and VTN deficient mice, we find that VTN is not required for PAI-1 to drive lung scarring. This result suggested the existence of a profibrotic interaction involving the VTN-binding site on PAI-1 with an unidentified ligand. Using an unbiased proteomic approach, we identified sortilin related receptor 1 (SorLA) as the most highly enriched PAI-1 binding partner in the fibrosing lung. Investigating the role of SorLA in pulmonary fibrosis demonstrated that deficiency of this protein protected against lung scarring in a murine model. We further found that SorLA is required for PAI-1 to promote scarring in mice, that both SorLA and PAI-1 protein levels are increased in human IPF explants, and that these proteins are associated in IPF tissue. Finally, confocal microscopy shows that expression of SorLA in CHO cells increases cell uptake of PAI-1, and these proteins colocalize in the cytoplasm. Together, these data elucidate a mechanism by which the potent profibrotic mediator PAI-1 drives lung fibrosis and implicate SorLA as a potential therapeutic target in IPF treatment.
Authors
Thomas H. Sisson, John J. Osterholzer, Lisa Leung, Venkatesha Basrur, Alexey I. Nesvizhskii, Natalya Subbotina, Mark Warnock, Daniel Torrente, Ammara Q. Virk, Sergey S. Gutor, Jeffrey C. Horowitz, Mary Migliorini, Dudley K. Strickland, Kevin K. Kim, Steven K. Huang, Daniel A. Lawrence
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