Immunology
Abstract
BACKGROUND. Susceptibility to human immunodeficiency virus type 1 (HIV-1) infection varies between individuals, but the biological determinants of acquisition risk remain poorly defined. METHODS. We conducted a case-control study nested within a high-risk cohort in Kenya. We compared the plasma extracellular RNA collected before HIV-1 acquisition with matched uninfected controls to identify immunological processes linked to infection risk. RESULTS. Individuals who later acquired HIV-1 exhibited upregulation of immune processes that facilitate viral infection, including T cell suppression, type II interferon and Th2 immune responses. In contrast, processes associated with antiviral defence and tissue repair, such as neutrophil and natural killer cell responses, type I interferon responses, wound healing, and angiogenesis, were downregulated. CONCLUSION. These findings highlight dampened antiviral immunity prior to exposure as a correlate of increased risk for subsequent HIV-1 acquisition. TRIAL NUMBERS. Not applicable. FUNDING. This work was supported by a Wellcome Trust Award (209289/Z/17/Z) and the Sub-Saharan African Network for TB/HIV Research Excellence (SANTHE) through the DELTAS Africa programme [Del-22-007], supported by the Science for Africa Foundation, Wellcome Trust, the UK Foreign, Commonwealth & Development Office, and the European Union. Additional support was provided by the Bill & Melinda Gates Foundation, Gilead Sciences Inc., Aidsfonds, and the Ragon Institute of Mass General, MIT, and Harvard. The cohort study was supported by PEPFAR through USAID. The views expressed are those of the authors.
Authors
Mwikali Kioko, Shaban Mwangi, Lynn Fwambah, Amin S. Hassan, Jason T. Blackard, Philip Bejon, Eduard J. Sanders, Thumbi Ndung'u, Eunice W. Nduati, Abdirahman I. Abdi
Abstract
Authors
Bingyu Yan, Jinwoo Lee, Suhas Srinivasan, Pedro Ambriz, Quanming Shi, Diana R. Dou, Srijana Davuluri, Swarna Nandyala, Adrianne Woods, Gwendolyn Leatherman, Yanding Zhao, Roman E. Reggiardo, Manasi Sawant, Hawa Racine Thiam, Ami A. Shah, David F. Fiorentino, Lorinda S. Chung, Howard Y. Chang
Abstract
Authors
Xinyu Wang, Yung-An Huang, Anshika Sethi, Christopher Yue, Sydney Brack, Aiswarya Chattuparambil Binoy, Lauren Crowther, Carol H. Yan, Adam Deconde, Anton Kushnaryov, Andrew M. Vahabzadeh-Hagh, Jacob Husseman, Maia Little, Allyssa Strohm, Lily Jih, Jonathan J. Lyons, David H. Broide, Taylor A. Doherty
Abstract
BACKGROUND. Infection by Trypanosoma cruzi, the agent of Chagas disease, is endemic to the Americas and can irreparably damage the cardiac and gastrointestinal systems during decades of parasite persistence. Diagnosis of chronic infection requires confirmation by multiple serological assays due to the imperfect performance of existing tests. Current serology tests were developed using small specimen sets predominantly from South America, and lower performance has been observed in patients who acquired infection in Central America and Mexico. METHODS. To improve Chagas disease serology, we evaluated antibody responses against the entire T. cruzi proteome with phage display immunoprecipitation sequencing and further evaluated high prevalence antigens by immunoassay. We utilized specimen sets representing Mexico, Central America and South America and varying cardiac disease presentations, from 185 cases and 143 controls. RESULTS. We identified over 1,300 antigenic T. cruzi peptides. A trans-sialidase antigen demonstrated high seroprevalence across all regions and has not previously been described as a diagnostic target. Orthogonal validation of this peptide demonstrated increased antibody reactivity for infections originating from Central America. CONCLUSION. This study provides proteome-wide identification of seroreactive T. cruzi peptides across a range of endemic populations not previously represented in antigen discovery and identifies a trans-sialidase peptide antigen (TS23) with potential for translation into diagnostic serological assays. TRIAL REGISTRATION. Not Applicable.
Authors
Hannah M. Kortbawi, Ryan J. Marczak, Jayant V. Rajan, Nash L. Bulaong, John E. Pak, Wesley Wu, Grace Wang, Anthea Mitchell, Aditi Saxena, Aditi Maheshwari, Rachel Alfaro Leone, Charles J. Fleischmann, Emily A. Kelly, Evan Teal, Rebecca L. Townsend, Susan L. Stramer, Emi E. Okamoto, Jacqueline E. Sherbuk, Eva H. Clark, Robert H. Gilman, Rony Pedro Colanzi, Efstathios D. Gennatas, Caryn Bern, Joseph L. DeRisi, Jeffrey D. Whitman
Abstract
Mycobacterium tuberculosis (Mtb) remains a global health crisis, ranking among the deadliest infectious diseases worldwide. In response to the World Health Organization’s call for therapeutic vaccines to complement antibiotic regimens and reduce tuberculosis (TB) treatment duration, we developed an intranasal DNA vaccine fusing the Mtb stringent response gene relMtb with the gene encoding the dendritic cell-targeting chemokine Mip3a/CCL20. Administered alongside the first-line regimen, this vaccine accelerated stable cure in immunocompetent murine TB models, reducing lung inflammation and eliciting robust and sustained RelMtb-stimulated T-cell responses systemically and locally. The Mip3a/relMtb vaccine enhanced dendritic cell recruitment, activation, and spatial coordination with T cells, suggesting improved innate-adaptive immune synergy. Notably, it augmented the efficacy of a novel drug-resistant TB regimen as well. Critically, the vaccine induced analogous antigen-stimulated T-cell immunity in nonhuman primates, the gold standard for preclinical TB vaccine evaluation, with responses detected in blood and bronchoalveolar lavage mirroring those observed in the murine models. These findings underscore the potential of this strategy to advance therapeutic TB vaccine development targeting Mtb persisters while providing a framework to define correlates of vaccine-mediated protection.
Authors
Styliani Karanika, Tianyin Wang, Addis Yilma, Jennie Ruelas Castillo, James T. Gordy, Hannah Bailey, Darla Quijada, Kaitlyn Fessler, Rokeya Tasneen, Elisa M. Rouse Salcido, Farah Shamma, Harley T. Harris, Fengyixin Chen, Rowan E. Bates, Heemee Ton, Jacob Meza, Yangchen Li, Alannah D. Taylor, Jean J. Zheng, Jiaqi Zhang, Theodoros Karantanos, Amanda R. Maxwell, Eric L. Nuermberger, J. David Peske, Richard B. Markham, Petros C. Karakousis
Abstract
Programmed cell death 1 ligand 1–targeted (PD-L1–targeted) immune checkpoint inhibitors are revolutionizing cancer therapy. However, strategies to induce endogenous PD-L1 degradation represent an emerging therapeutic paradigm. Here, we identified proanthocyanidins (PC) as a potent inducer of PD-L1 degradation through an endoplasmic reticulum–associated degradation (ERAD) mechanism. Mechanistically, PC exerted dual effects: First, it targeted and stabilized LKB1 to activate AMPK in tumor cells, subsequently inducing the phosphorylation of PD-L1 at Ser195 — a disruption that in turn impaired glycosylation of PD-L1 and promoted its retention in the ER. Second, PC directly bound to the E3 ubiquitin ligase SYVN1 to increase its protein stability, which strengthened PD-L1–SYVN1 binding, thereby accelerating K48-linked ubiquitination and proteasomal degradation of ER-retained PD-L1. This cascade culminated in the activation of CD8+ T cell–dominated antitumor immune responses, accompanied by suppression of myeloid-derived suppressor cells and regulatory T cells. In preclinical models of lung and colorectal cancer, PC exhibited synergistic antitumor efficacy when combined with anti–cytotoxic T lymphocyte antigen 4 (anti–CTLA-4) antibodies. Notably, PC also potently inhibited the progression of azoxymethane/dextran sodium sulfate–induced orthotopic colorectal cancer in mice. Collectively, our findings unveil an antitumor mechanism of PC, establishing this small-molecule compound as an ERAD pathway–exploiting immune checkpoint modulator with promising translational potential for cancer therapy.
Authors
Mengting Xu, Xuwen Lin, Hanchi Xu, Hongmei Hu, Xinying Xue, Qing Zhang, Dianping Yu, Saisai Tian, Mei Xie, Linyang Li, Xiaoyu Tao, Xinru Li, Simeng Li, Shize Xie, Yating Tian, Xia Liu, Hanchen Xu, Qun Wang, Weidong Zhang, Sanhong Liu
Abstract
Traditional polysaccharide vaccines are constrained by streptococcus pneumoniae diversity. We propose a protein-based pneumococcal vaccine (PBPV) — formulated with conserved surface proteins P3296, P5668, PRx1, and pneumolysin (Ply) — that could potentially offer superior immune breadth independent of capsular polysaccharide serotypes. Here, we evaluated the multifunctional antibody responses induced by PBPV, including immunogenicity, Ply neutralization, opsonophagocytic activity (OPA), and such nonopsonic functions as NK cell activation (ADNKA), antibody-dependent cellular phagocytosis, and neutrophil phagocytosis (ADNP) in a cohort of 50- to 69-year-olds. While PBPV showed shorter-lasting immune responses, including reduced Ply-neutralizing capacity, it provided broader cross-serotype protection than 23-valent pneumococcal polysaccharide vaccine. Correlation analysis identified distinct PspA-specific IgG subclass roles: P3296-IgG1 correlated with OPA, and IgG3 correlated with ADNKA/ADNP; P5668-IgG2 correlated with ADNKA/ADNP, and IgG3 correlated with OPA; and PRx1-IgG2 correlated with OPA, and IgG3 correlated with ADNKA. Critically, while no efficacy data have yet confirmed the protective effect of PBPV, its targeting of conserved proteins rather than capsular polysaccharides enables simplified manufacturing and expanded coverage, positioning it as a promising alternative to traditional multipolysaccharide vaccines.
Authors
Kaiyi Li, Jinglu Yang, Xiaobing Zhai, Jinbo Gou, Xiuwen Sui, Bochao Wei, Yuan Wang, Xiaoling Su, Xiaoyun Yang, Shiqin Jin, Xuan Zhou, Yuxuan Zhang, Tao Zhu, Junxiang Wang, Zhongfang Wang
Abstract
Authors
Maiko Sezaki, Tian Li, Mingzhe Pan, Zhihong Wang, Jie Bai, Justin G. Horowitz, Julia Z. Xu, Gang Huang
Abstract
The regulation of the programmed cell death protein 1 (PD-1) gene, PDCD1, has been widely explored at transcription and posttranslational levels in T cell function and tumor immune evasion. However, the mechanism for PDCD1 dysregulation at the posttranscriptional level remains largely unknown. Here, we identify protein arginine methyltransferase 5 (PRMT5) as a RNA binding protein in a methyltransferase activity–independent manner, which promotes PDCD1 decay with WD repeat domain 77 protein (WDR77) and Argonaute2. Furthermore, the type-I IFN/STAT1 pathway transcriptionally activates PRMT5 and WDR77, thus enhancing PRMT5/WDR77 binding on a conserved AU-rich element of PDCD1 3′ UTR. Functionally, conditional knockout of either PRMT5 or WDR77 in T cells disrupts T cell effector function and sensitizes the tumors to anti–PD-1 therapy. Clinically, PRMT5 and WDR77 expression in tumor-infiltrating T cells are negatively correlated with PDCD1 expression and renders tumors resistant to PD-1–targeted immunotherapy. Moreover, fludarabine targeting STAT1 in combination with anti–PD-1 has a synergetic effect on suppressing tumor growth in mice. Overall, this study reveals that the RNA binding–dependent function of PRMT5 regulates PDCD1 and T cell effector function with WDR77 and identifies potential combinatorial therapeutic strategies for enhancing antitumor efficacy.
Authors
Yinmin Gu, Yongbo Pan, Chang Pan, Qiang Pang, Zhantong Tang, Yiwen Chen, Haojing Zang, Xiaodong Wang, Chang Huang, Qingqing Zhang, Facai Yang, Xiaofeng Zhu, Yibi Zhang, Xujie Zhao, Shan Gao
Abstract
MAP kinase kinase kinase kinase (MAP4K) family kinases are key kinases for T-cell-mediated immune responses; however, in vivo roles of MAP4K2 in immune regulation remain unclear. Using T-cell-specific Map4k2 conditional knockout (T-Map4k2 cKO) mice, single-cell RNA sequencing (scRNA-seq), and mass spectrometry analysis, we found that MAP4K2 interacted with DDX39B, induced forkhead box protein P3 (FOXP3) gene expression, and promoted Treg differentiation. Mechanistically, MAP4K2 directly phosphorylated the DEAD box protein DDX39B, leading to DDX39B nuclear translocation and subsequent Foxp3 RNA splicing. MAP4K2-induced FOXP3 mRNA levels were abolished in DDX39B knockout T cells. Furthermore, T-Map4k2 cKO mice displayed the reduction of Treg population and the sustained inflammation during remission phase of EAE autoimmune disease model. Remarkably, the anti-PD-1 immunotherapeutic effect on pancreatic cancer was significantly improved in T-Map4k2 cKO mice, Treg-specific Map4k2-deficient mice, adoptively transferred chimeric mice, or MAP4K2-inhibitor-treated mice. Consistently, scRNA-seq analysis of human pancreatic patients showed increased MAP4K2 levels in infiltrating Treg cells. Collectively, MAP4K2 promotes Treg differentiation by inducing DDX39B nuclear translocation, leading to the attenuation of antitumor immunity.
Authors
Huai-Chia Chuang, Chia-Wen Wang, Chia-Hsin Hsueh, Yu-Zhi Xiao, Ching-Yi Tsai, Pu-Ming Hsu, Evelyn L. Tan, Hsien-Yi Chiu, Tse-Hua Tan
Copyright © 2026 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)