Immunology
Abstract
HIV/SIV-specific CD8+ T cell responses are typically unable to control viral rebound following antiretroviral therapy (ART) interruption (ATI). To investigate whether enhancing the magnitude and activation of SIV-specific CD8+ T cells at the time of ATI can improve the immune interception of reactivating SIV infections we vaccinated SIVmac239-infected rhesus macaques (RMs) on ART, boosting immediately prior to ATI, with a nucleoside-unmodified mRNA vaccine expressing SIVmac239 Gag (mRNA/SIVgag) alone or in combination with Nef (mRNA/SIVnef) and Pol (mRNA/SIVpol). The mRNA/SIVgag vaccine was effective in boosting Gag-specific CD8+ T cells in blood and lymphoid tissues. Following ATI, the mRNA/SIV-Gag vaccine group showed a significant delay in time to measurable viral rebound compared to controls, and manifested lower plasma viral loads (PVL) for up to 6 weeks after rebound. Similarly, RMs that received mRNA/SIVgag, mRNA/SIVnef, and mRNA/SIVpol also manifested a delay in SIV rebound compared to controls, suggesting that boosting SIV-specific CD8+ T cells during ATI can enhance early immune targeting of reactivating SIV infections. However, viral control was not sustained long-term as PVLs were similar across vaccinees and controls by 24 weeks post-rebound, highlighting the need for adjunctive therapies to improve the durability of virologic control elicited by CD8+ T cell-targeting vaccines.
Authors
Were R. Omange, Benjamin D. Varco-Merth, Omo Fadeyi, Alejandra Marenco, Hiroshi Takata, Derick M. Duell, William D. Goodwin, Paula Armitage, Christine M. Fennessey, Emek Kose, Taina T. Immonen, Ewelina Kosmider, William J. Bosche, Randy Fast, Chris Homick, Kelli Oswald, Rebecca Shoemaker, Rachele Bochart, Rhonda MacAllister, Caralyn S. Labriola, Jeremy V. Smedley, Michael K. Axthelm, Paul T. Edlefsen, Brandon F. Keele, Jeffrey D. Lifson, Janina Gergen, Benjamin Petsch, Susanne Rauch, Louis J. Picker, Afam A. Okoye
Abstract
The PIM kinase family is critically involved in tumorigenesis, yet its role in primary T cells is understudied. We reported that PIM2, distinct from the other two isoforms, inhibits T-cell responses to alloantigen. Here, we further established PIM2 as a key negative regulator in anti-tumor immunity. Pim2 deficiency in tumor antigen-specific or polyclonal T cells enhanced their ability to control tumor growth in murine breast cancer, melanoma and leukemia models. Pim2 deficiency enhanced cytokine production and metabolic activities in tumor-infiltrating CD8 T cells. Pim2 deficiency increased TCF1 expression and memory-like phenotype in CD8 T cells from lymphoid organs. Mechanistically, PIM2 facilitated LC3 lipidation, P62 degradation and autophagic flux in T cells, leading to impaired glycolysis and effector cytokine production. Furthermore, through modulating VPRBP kinase phosphorylation, PIM2 inhibited histone methyltransferase activity of EZH2 in CD8 T cells, causing disrupted memory-like phenotype. Notably, the PIM2 inhibitor JP11646 markedly enhanced antitumor T-cell response. The immunosuppressive role of PIM2 was validated in human T cells, where inhibition of PIM2 enhanced antitumor responses in engineered human T cells including melanoma-specific TCR-T cells and CD19CAR-T cells. Collectively, PIM2 represents a promising target for improving cancer immunotherapy through enhancing effector differentiation and persistence of CD8 T cells.
Authors
Yongxia Wu, Linlu Tian, Allison Pugel, Reza Alimohammadi, Qiao Cheng, Weiguo Cui, Michael I. Nishimura, Lauren E. Ball, Chien-Wei Lin, Shikhar Mehrotra, Andrew S. Kraft, Xue-Zhong Yu
Abstract
Glioblastoma (GBM) is a highly lethal brain tumor with limited treatment options and resistance to immune checkpoint inhibitors due to its immunosuppressive tumor microenvironment (TME). Here, we identify OLIG2 as a key regulator of immune evasion in GBM stem-like cells, inhibiting CD8+ T cell-dependent antitumor immunity, while promoting pro-tumor macrophages polarization. Mechanistically, OLIG2 recruits HDAC7 to repress CXCL10 transcription, inducing STAT3 activation in tumor-associated macrophages (TAMs) and decreasing CD8+ T cell infiltration and activation. Genetic deletion of OLIG2 significantly increases CXCL10 secretion, shifting TAMs toward an anti-tumor phenotype and enhancing CD8+ T cell activities. Furthermore, upregulated OLIG2 expression is correlated to resistance to immune checkpoint inhibitors (ICIs) in GBM patients. OLIG2 inhibition by either genetic deficiency or pharmacological targeting with CT-179 sensitizes GBM tumors to anti-PD-L1 therapy, enhancing antitumor immune responses and prolonging survival. Our findings reveal OLIG2+ glioma stem-like cells as critical mediators of immune evasion and identify the OLIG2/HDAC7/CXCL10 axis as a potential therapeutic target to enhance immune checkpoint inhibitors efficacy and to improve immunotherapy outcomes in aggressive GBM.
Authors
Xinchun Zhang, Jinjiang Xue, Cunyan Zhao, Chenqiuyue Zeng, Jiacheng Zhong, Gangfeng Yu, Xi Yang, Yao Ling, Dazhen Li, Jiaxiao Yang, Yun Xiu, Hongda Li, Shiyuan Hong, Liangjun Qiao, Song Chen, Q. Richard Lu, Yaqi Deng, Zhaohua Tang, Fanghui Lu
PARP inhibitors restore NK cell function via secretory crosstalk with tumor cells in prostate cancer
Abstract
Prostate cancer (PCa) is one of the most frequently diagnosed malignancies and the main cause of cancer-related death in men worldwide. Poly (ADP-ribose) polymerase (PARP) inhibitors have been approved for the treatment of PCa harboring BRCA1/2 mutations. While the survival benefits conferred by PARP inhibitors (PARPi) may extend beyond this specific patient population based on evidence from recent clinical trials, the underlying mechanisms remain unexplored. Here, we demonstrate that PARPi substantially restore natural killer (NK) cell functions by promoting cyclophilin A (CypA) secretion from PCa cells, which correlates with improved prognosis in PCa patients from our and public cohorts. Mechanistically, tumor-derived CypA specifically from PCa cells binds to ANXA6 and activates the downstream FPR1 signaling pathway, leading to increased mitochondrial oxidative phosphorylation and NK cell activation. Pharmacological inhibition of CypA blocks the FPR1-AKT signaling and diminishes the cytotoxic effects of NK cells, thereby compromising the therapeutic efficacy of PARPi against PCa. Conversely, combining NK cell adoptive transfer therapy with PARPi markedly prolongs survival in mice bearing PCa. Collectively, we reveal a unique secretory crosstalk between PCa cells and NK cells induced by PARPi and propose a promising strategy for treating PCa.
Authors
Zheng Chao, Le Li, Xiaodong Hao, Hao Peng, Yanan Wang, Chunyu Zhang, Xiangdong Guo, Peikun Liu, Sheng Ma, Junbiao Zhang, Guanyu Qu, Yuzheng Peng, Zhengping Wei, Jing Luo, Bo Liu, Peixiang Lan, Zhihua Wang
Abstract
Atopic dermatitis (AD) is a chronic inflammatory skin condition characterized by a type 2 immune response that is not fully understood. Single-cell RNA sequencing (scRNA-seq) of human AD skin and murine models of type 2 inflammation identified transcriptionally distinct fibroblast clusters, revealing unique, IL-4Rɑ-dependent populations of immune-acting fibroblasts. These unbiased findings prompted further investigation into the role of dermal fibroblasts during allergic inflammation. These studies demonstrated that, in an inflammatory environment including TNFɑ, IL-1β and IL-17A, IL-4 and IL-13 stimulate both mouse and human fibroblasts to produce multiple chemokines, including Ccl8, which activates Ccr3 to attract T-cells. In the skin, fibroblasts are the primary source of many of these chemokines, and targeted deletion of IL--4rɑ in mouse fibroblasts reduces T-cell infiltration in a mouse model of AD. Additionally, pharmacologic inhibition of Ccr3, the receptor shared by many chemokines produced by fibroblasts, decreases T-cell infiltration and skin inflammation in AD mouse models. These findings demonstrate that dermal fibroblasts are more than passive structural cells; they actively participate in the type 2 immune response and contribute to AD by producing chemokines that increase inflammation. Targeting the functions of immune-acting fibroblasts could offer an alternative therapeutic approach for AD.
Authors
Tomofumi Numata, Michael Shia, Yoshiyuki Nakamura, Fengwu Li, Hung Chan, Teruaki Nakatsuji, Kellen J. Cavagnero, Jared Simmons, Henry Li, Aaroh Anand Joshi, Marta Palomo-Irigoyen, Richard L. Gallo
Abstract
Immunotherapy has been effective in many cancer types but has failed in multiple clinical trials in prostate cancers, with the underlying mechanisms remaining largely unclear. Here, we demonstrate that androgen receptor pathway inhibitor (ARPI) plus irradiation (IR) triggered robust anticancer immunity in prostate cancers in both patients and mice. We show that androgen-activated AR suppressed innate immune signaling by inducing inhibitor of nuclear factor kappa-B kinase subunit epsilon (IKBKE) gene repression through HDAC2 interaction with an IKBKE enhancer RNA (IKBKE eRNA, or IKBKE-e). ARPI treatment caused IKBKE derepression and enhanced an IR-induced innate immune response via action of RIG-I and MDA5 dsRNA sensors. IKBKE-e ablation largely enhanced innate immunity in prostate cancer cells in culture and anticancer immunity in mice. Our results revealed AR, HDAC2, and IKBKE eRNA as critical intrinsic immune suppressors in prostate cancer cells, suggesting that rejuvenating inhibitor of nuclear factor kappa-B kinase subunit epsilon (IKKε) signaling by targeting IKBKE-e is an actionable strategy to elicit synthetic anticancer immunity in immunologically “cold” cancers such as prostate cancer.
Authors
Xiang Li, Rui Sun, Hao Li, Jacob J. Orme, Xu Zhang, Yu Hou, Sean S. Park, Yu Zhang, Yi He, Liguo Wang, Veronica Rodriguez-Bravo, Josep Domingo-Domenech, Shancheng Ren, Dan Xia, Guanghou Fu, Zhankui Jia, Haojie Huang
Abstract
Despite overexpression of N-acetyltransferase 10 (NAT10) in colorectal cancer (CRC), its immunomodulatory role in the tumor microenvironment remains elusive. Here, we reveal that NAT10 promotes immune evasion through N4-acetylcytosine–dependent (ac4C-dependent) mRNA stabilization. Using syngeneic mouse models (MC38/CT-26), intestinal epithelial-cell specific Nat10 conditional KO (Nat10cKO) mice, patient-derived organoids, and clinical specimens, we show that Nat10 ablation enhanced CD8+ T cell–mediated antitumor immunity. Single-cell RNA-seq revealed increased cytotoxic CD8+ T cell infiltration in Nat10cKO tumors, which was corroborated by the inverse correlation of tumoral NAT10 expression and CD8+ T cell number in clinical specimens. Multi-omics integration analysis identified DKK2 as the predominant NAT10-regulated transcript. NAT10 stabilized DKK2 mRNA via ac4C modification, leading to high expression of the DKK2 protein. Secreted DKK2 engaged LRP6 receptors to activate AKT-mTOR signaling, inducing cholesterol accumulation in CD8+ T cells and impairing their cytotoxicity. Pharmacological NAT10 inhibition (Remodelin treatment) or DKK2 neutralization restored CD8+ T cell function and synergized with anti–PD-1 therapy. Our findings establish the NAT10/DKK2/LRP6/AKT-mTOR/cholesterol axis as a critical regulator of CD8+ T cell dysfunction in CRC, positioning NAT10/DKK2 as a potential target to enhance immunotherapy efficacy.
Authors
Mengmeng Li, Xiaoya Zhao, Jun Wu, Shimeng Zhou, Yao Fu, Chen Chen, Zhuang Ma, Jiawen Xu, Yun Qian, Zhangding Wang, Bo Wang, Qiang Wang, Qingqing Ding, Changyu Chen, Honggang Wang, Xiaozhong Yang, Weijie Dai, Wenjie Zhang, Shouyu Wang
Abstract
Mutation-associated neoantigens (MANAs) are highly cancer-specific targets for immunotherapy where peptides derived from intracellular mutant proteins are presented on the cell surface via HLA molecules. T cell–engaging bispecific antibodies and CAR T cells can target MANAs to eliminate cancer cells via T cell activation. However, the low antigen density of MANAs on the cell surface can limit therapeutic efficacy. Here, we investigated whether increasing the affinity of the H2 single-chain variable fragment (scFv) targeting the p53 R175H MANA (HMTEVVRHC presented on HLA-A*02:01) improves its therapeutic effect. We identified higher-affinity H2 variants via phage biopanning and a thiocyanate elution method. Increasing bispecific antibody affinity to the low nanomolar range increased cancer cell killing and tumor control in mouse xenograft models without sacrificing antigen specificity. We next asked how increasing scFv affinity impacts CAR T cell function — a matter of debate. We appended each variant scFv to a CD28z CAR, CD3γ, or the T cell receptor. In striking contrast to the bispecific antibody results, increasing CAR affinity decreased function in each CAR format due to lower T cell activation upon interaction with target cancer cells. These results have important implications for the design of future immunotherapeutic approaches targeting low-density antigens.
Authors
Sarah R. DiNapoli, Katharine M. Wright, Brian J. Mog, Alexander H. Pearlman, Tushar D. Nichakawade, Nikita Marcou, Emily Han-Chung Hsiue, Michael S. Hwang, Jacqueline Douglass, Qiang Liu, Evangeline Watson, Marco Dal Molin, Joshua D. Cohen, Maria Popoli, Suman Paul, Maximilian F. Konig, Nicolas Wyhs, P. Aitana Azurmendi, Stephanie Glavaris, Jiaxin Ge, Tolulope O. Awosika, Jin Liu, Kathleen L. Gabrielson, Sandra B. Gabelli, Drew M. Pardoll, Chetan Bettegowda, Nickolas Papadopoulos, Kenneth W. Kinzler, Shibin Zhou, Bert Vogelstein
Abstract
Epidermal growth factor receptor (EGFR)-activating mutations are established biomarkers of resistance to immune checkpoint blockade (ICB) in lung cancer, yet the precise molecular mechanism and effective therapeutic strategies remain elusive. In this study, we show that EGFR overexpression and amplification recapitulate the negative impact of EGFR driver mutations to ICB response, indicating a proactive involvement of EGFR signaling in antagonizing antitumor immune response. Functional studies unveil that EGFR activation suppresses cellular response to interferon-gamma (IFN-γ) following ICB treatment across multiple cancer models. This impairment in IFN-γ responsiveness further limits the upregulation of T cell-recruiting chemokines and antigen presentation, resulting in reduced T cell infiltration and activation, ultimately undermining antitumor immunity. Mechanistically, EGFR promotes SHP2 activation to accelerate STAT1 dephosphorylation, leading to premature termination of the IFN-γ response. SHP2 inhibition restored ICB sensitivity in EGFR-activated tumors, significantly reducing tumor burden while maintaining a favorable safety profile. Our findings suggest that EGFR/SHP2 axis functions as a molecular brake to disrupt the initiation and amplification of IFN-γ mediated anti-tumor response during immunotherapy. This discovery unveils a potential avenue to overcome immunotherapy resistance in EGFR-driven tumors, particularly lung cancer, through SHP2-targeted combination strategies.
Authors
Wei-Tao Zhuang, Lan-Lan Pang, Li-Yang Hu, Jun Liao, Jian-Hua Zhan, Ting Li, Ri-Xin Chen, Jia-Ni Zheng, An-Lin Li, Wen-Yan Yu, Tian-Qin Mao, Liang Chen, Yu-Jian Huang, Shao-Dong Hong, Jing Li, Jun-Han Wu, Yi-Ming Zeng, Meng-Juan Yang, Hai-Qing Zeng, Ya-Xiong Zhang, Li Zhang, Wen-Feng Fang
Abstract
Short-lived, clade-specific immune responses with limited mucosal priming are limitations faced by current COVID-19 mRNA vaccines. We have developed a nasal booster vaccine candidate that induced robust, sustained, cross-clade, systemic and mucosal protective immunity. Two recombinant Clec9A-specific monoclonal antibodies fused to the Receptor Binding Domain (RBD) from Omicron XBB.1.5 and SARS-CoV-1, respectively were generated. In Comirnaty mRNA-vaccinated mice, boosting with both constructs combined (Clec9AOMNI) induced cross-clade neutralizing antibodies (nAbs) and T-cell responses that were greater in magnitude and more sustained compared to bivalent Comirnaty (BC) mRNA vaccine booster. Persistence of RBD-specific follicular helper CD4+ T cells, germinal centre B cells, and long-lived plasma cells that facilitated affinity maturation, correlated with detection of triple cross-reactive B cells binding the RBDs of SARS-CoV-2 ancestral, XBB.1.5, and SARS-CoV-1. Remarkably, intranasal boosting with Clec9AOMNI elicited robust and durable immunity across the upper and lower airways while concurrently boosting the systemic immunity to levels matching or exceeding those from systemic boosting. Correspondingly, Clec9AOMNI nasal booster conferred superior protection against SARS-CoV-2 challenge compared to BC mRNA booster, with undetectable viral titers in the respiratory tract. Hence, Clec9AOMNI is a promising nasal booster vaccine candidate that has the potential to mitigate pandemic threats from emerging sarbecoviruses.
Authors
You Zhi Nicholas CHEANG, Wee Chee Yap, Kirsteen M. TULLETT, Xinlei QIAN, Peck S. TAN, Kiren PURUSHOTORMAN, Wan Yi TAN, Yun Yan MAH, Paul MACARY, Chee Wah TAN, Mireille H. LAHOUD, Sylvie ALONSO
Copyright © 2026 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)