Infectious disease
Abstract
Neonatal herpes simplex virus (HSV) infection is a devastating disease with substantial morbidity and mortality. The genetic basis of susceptibility to HSV in neonates remains undefined. We investigated a male infant with neonatal skin/eye/mouth (SEM) HSV1 disease who had complete recovery after acyclovir but developed HSV1 encephalitis at 1 year of age. Immune work up showed an anergic peripheral blood monocyte cytokine (PBMC) response to TLR3 stimulation but no other TLRs. Exome sequencing identified rare missense variants in IRF7 and UNC93B1. PBMC single cell RNA sequencing done during childhood revealed decreased expression of several innate immune genes and a repressed TLR3 pathway signature at baseline in several immune cell populations, including CD14 monocytes. Functional studies in fibroblasts and THP-1 showed that both variants individually suppressed TLR3-driven IRF3 promoter activity and type I interferon response in vitro. Furthermore, fibroblasts expressing the IRF7 and UNC93B1 variants had higher intracellular viral titers with blunting of the type I interferon response upon HSV1 challenge. This study reports an infant with recurrent HSV1 disease complicated by encephalitis associated with deleterious variants in IRF7 and UNC93B1 genes. Our results suggest that TLR3 pathway mutations may predispose neonates to recurrent severe HSV.
Authors
Megan H. Tucker, Wei Yu, Heather L. Menden, Sheng Xia, Carl F. Schreck, Margaret I. Gibson, Daniel A. Louiselle, Tomi Pastinen, Nikita Raje, Venkatesh Sampath
Abstract
Ferritin, a key regulator of iron homeostasis in macrophages, has been reported to confer host defenses against Mycobacterium tuberculosis (Mtb) infection. Nuclear receptor coactivator 4 (NCOA4) was recently identified as a cargo receptor in ferritin degradation. Here, we show that Mtb infection enhanced NCOA4-mediated ferritin degradation in macrophages, which in turn increased the bioavailability of iron to intracellular Mtb and therefore promoted bacterial growth. Of clinical relevance, the upregulation of FTH1 in macrophages was associated with tuberculosis (TB) disease progression in humans. Mechanistically, Mtb infection enhanced NCOA4-mediated ferritin degradation through p38/AKT1- and TRIM21-mediated proteasomal degradation of HERC2, an E3 ligase of NCOA4. Finally, we confirmed that NCOA4 deficiency in myeloid cells expedites the clearance of Mtb infection in a murine model. Together, our findings revealed a strategy by which Mtb hijacks host ferritin metabolism for its own intracellular survival. Therefore, this represents a potential target for host-directed therapy against tuberculosis.
Authors
Youchao Dai, Chuanzhi Zhu, Wei Xiao, Kaisong Huang, Xin Wang, Chenyan Shi, Dachuan Lin, Huihua Zhang, Xiaoqian Liu, Bin Peng, Yi Gao, Cui Hua Liu, Baoxue Ge, Stefan H.E. Kaufmann, Carl G. Feng, Xinchun Chen, Yi Cai
Abstract
BACKGROUND Lower respiratory tract infection (LRTI) is a leading cause of death in children worldwide. LRTI diagnosis is challenging because noninfectious respiratory illnesses appear clinically similar and because existing microbiologic tests are often falsely negative or detect incidentally carried microbes, resulting in antimicrobial overuse and adverse outcomes. Lower airway metagenomics has the potential to detect host and microbial signatures of LRTI. Whether it can be applied at scale and in a pediatric population to enable improved diagnosis and treatment remains unclear.METHODS We used tracheal aspirate RNA-Seq to profile host gene expression and respiratory microbiota in 261 children with acute respiratory failure. We developed a gene expression classifier for LRTI by training on patients with an established diagnosis of LRTI (n = 117) or of noninfectious respiratory failure (n = 50). We then developed a classifier that integrates the host LRTI probability, abundance of respiratory viruses, and dominance in the lung microbiome of bacteria/fungi considered pathogenic by a rules-based algorithm.RESULTS The host classifier achieved a median AUC of 0.967 by cross-validation, driven by activation markers of T cells, alveolar macrophages, and the interferon response. The integrated classifier achieved a median AUC of 0.986 and increased the confidence of patient classifications. When applied to patients with an uncertain diagnosis (n = 94), the integrated classifier indicated LRTI in 52% of cases and nominated likely causal pathogens in 98% of those.CONCLUSION Lower airway metagenomics enables accurate LRTI diagnosis and pathogen identification in a heterogeneous cohort of critically ill children through integration of host, pathogen, and microbiome features.FUNDING Support for this study was provided by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the National Heart, Lung, and Blood Institute (UG1HD083171, 1R01HL124103, UG1HD049983, UG01HD049934, UG1HD083170, UG1HD050096, UG1HD63108, UG1HD083116, UG1HD083166, UG1HD049981, K23HL138461, and 5R01HL155418) as well as by the Chan Zuckerberg Biohub.
Authors
Eran Mick, Alexandra Tsitsiklis, Jack Kamm, Katrina L. Kalantar, Saharai Caldera, Amy Lyden, Michelle Tan, Angela M. Detweiler, Norma Neff, Christina M. Osborne, Kayla M. Williamson, Victoria Soesanto, Matthew Leroue, Aline B. Maddux, Eric A.F. Simões, Todd C. Carpenter, Brandie D. Wagner, Joseph L. DeRisi, Lilliam Ambroggio, Peter M. Mourani, Charles R. Langelier
Abstract
BACKGROUND. Refractory CMV viremia and disease are associated with significant morbidity and mortality in recipients of hematopoietic stem cell transplant (HCT). METHODS. In Phase I/II trials, we treated 67 subjects for CMV viremia or disease arising after allogeneic hematopoietic cell transplant with adoptive transfer of banked off-the-shelf, 3rd party, CMVpp65-sensitized T cells (CMVpp65-VSTs). All were evaluable for toxicity and 59 for response. Evaluable subjects had CMV disease or persisting viremia that had failed at least two weeks of induction therapy with a median of 3 antiviral drugs; 84.7% had >3/11 high risk features. CMVpp65-VSTs were specific for 1-3 CMVpp65 epitopes, presented by a limited set of HLA class I or II alleles, and were selected based on high resolution HLA matching at 2/10 HLA alleles and matching for subject and subject’s HCT donor for ≥1 allele through which the CMVpp65-VSTs were restricted. RESULTS. T-cell infusions were well tolerated. Of 59 subjects evaluable for response, 38 (64%) achieved complete or durable partial responses. CONCLUSIONS. Recipients responding to CMVpp65VSTs experienced an improved overall survival. Of the risk factors evaluated, transplant type, recipient CD4+ and CD8+ T-cell levels prior to adoptive therapy, and the HLA-restriction of CMVpp65-VSTs infused each significantly affected responses. In addition, CMVpp65-specific T cells of HCT donor or recipient origin contribute to the durability of both complete and partial responses. TRIAL REGISTRATION. The trials describe were registered with the NIH as follows: NCT00674648, NCT01646645 and NCT02136797. They were single center investigator-initiated trials and were not industry sponsored. FUNDING. This study was supported by funding from the National Institute of Health (P01 CA23766, R21 CA162002 and P30 CA008748), the Aubrey Fund, Claire Tow Foundation, Major Family Foundation, “Rick” Eisemann Pediatric Research Fund, Banbury Foundation, Edith Robertson Foundation, and Larry Smead Foundation.
Authors
Susan E. Prockop, Aisha N. Hasan, Ekaterina Doubrovina, Parastoo B. Dahi, M. Irene Rodriguez-Sanchez, Michael Curry, Audrey Mauguen, Genovefa A. Papanicolaou, Yiqi Su, JinJuan Yao, Maria E. Arcila, Farid Boulad, Hugo Castro-Malaspina, Christina Cho, Kevin J. Curran, Sergio Giralt, Nancy A Kernan, Guenther Koehne, Ann Jakubowski, Esperanza Papadopoulos, Miguel-Angel Perales, Ioannis Politikos, Keith J. Price, Annamalai Selvakumar, Craig S. Sauter, Roni Tamari, Teresa Vizconde, James W. Young, Richard J. O'Reilly
Abstract
Mucosal infections pose a significant global health burden. Antigen-specific tissue resident T cells are critical to maintaining barrier immunity. Previous studies in the context of systemic infection suggest that memory CD8 T cells may also provide innate-like protection against antigenically unrelated pathogens independent of TCR engagement. Whether "bystander T cell activation" is also an important defense mechanism in the mucosa is poorly understood. Here, we investigated if innate-like memory CD8 T cells could protect against a model mucosal virus infection, herpes simplex virus 2 (HSV-2). We found that immunization with an irrelevant antigen delayed disease progression from lethal HSV-2 challenge, suggesting that memory CD8 T cells may mediate protection despite the lack of antigen-specificity. Upon HSV-2 infection, we observed an early infiltration, rather than substantial local proliferation, of antigen-non-specific CD8 T cells, which became bystander-activated only within the infected mucosal tissue. Critically, we show that bystander-activated CD8 T cells are sufficient to reduce early viral burden after HSV-2 infection. Finally, local cytokine cues within the tissue microenvironment after infection were sufficient for bystander activation of mucosal tissue memory CD8 T cells from mice and humans. Altogether, our findings suggest that local bystander-activation of CD8 memory T cells contribute a fast and effective innate-like response to infection in mucosal tissue.
Authors
Tanvi Arkatkar, Veronica A. Davé, Irene Cruz Talavera, Jessica B. Graham, Jessica L. Swarts, Sean M. Hughes, Timothy A. Bell, Pablo Hock, Joe Farrington, Ginger D. Shaw, Anna C. Kirby, Michael Fialkow, Meei-Li Huang, Keith R. Jerome, Martin T. Ferris, Florian Hladik, Joshua T. Schiffer, Martin Prlic, Jennifer M. Lund
Abstract
Induction of lipid-laden foamy macrophages is a cellular hallmark of tuberculosis (TB) disease, which involves transformation of infected phagolysomes from a site of killing into a nutrient-rich replicative niche. Here we show that a terpenyl nucleoside shed from Mycobacterium tuberculosis (Mtb), 1-tuberculosinyladenosine (1-TbAd), causes lysosomal maturation arrest and autophagy blockade, leading to lipid storage in M1 macrophages. Pure 1-TbAd, or infection with terpenyl nucleoside-producing Mtb, caused intralysosomal and peribacillary lipid storage patterns that match both the molecules and subcellular locations known in foamy macrophages. Lipidomics showed that 1-TbAd induced storage of triacylglycerides and cholesterylesters, and 1-TbAd increased Mtb growth under conditions of restricted lipid access in macrophages. Further, lipidomics dentified 1-TbAd induced lipid substrates that define Gaucher's disease, Wolman's disease and other inborn lysosomal storage diseases. These data identify genetic and molecular causes of Mtb-induced lysosomal failure, leading to successful testing of an gonist of TRPML1 calcium channels that reverses lipid storage in cells. These data establish the host-directed cellular functions of an orphan effector molecule that promotes survival in macrophages, providing both an upstream cause and detailed picture of lysosome failure in foamy macrophages.
Authors
Melissa Bedard, Sanne van der Niet, Elliott M. Bernard, Gregory H. Babunovic, Tan-Yun Cheng, Beren Aylan, Anita E. Grootemaat, Sahadevan Raman, Laure Botella, Eri Ishikawa, Mary P. O'Sullivan, Seonadh O'Leary, Jacob A. Mayfield, Jeffrey Buter, Adriaan J. Minnaard, Sarah M. Fortune, Leon O. Murphy, Daniel S. Ory, Joseph Keane, Sho Yamasaki, Maximiliano Gabriel Gutierrez, Nicole van der Wel, D. Branch Moody
Abstract
Uncontrolled inflammation occurred in sepsis results in multiple organ injuries and shock, which contributes to the death of sepsis patients. However, the regulatory mechanisms that restrict excessive inflammation are still elusive. Here we identified an immunoglobulin-like receptor called Signaling Lymphocyte Activation Molecular Family-7 (SLAMF7), as a key suppressor of inflammation during sepsis. We found that the expression of SLAMF7 on monocytes/ macrophages was significantly elevated in patients with sepsis and septic mice. SLAMF7 attenuated TLR-dependent MAPK and NF-κB signaling activation in macrophages by co-operating with Src homology 2-containing inositol ‑5'‑ phosphatase1 (SHIP1). Furthermore, SLAMF7 interacted with SHIP1 and TNF receptor associated factor 6 (TRAF6) to inhibit K63 ubiquitination of TRAF6. In addition, we found that tyrosine phosphorylation sites within the intracellular domain of SLAMF7 and the phosphatase domain of SHIP1 were indispensable for the interaction of SLAMF7/SHIP1/TRAF6 and SLAMF7-mediated modulation of cytokine production. Finally, we demonstrated that SLAMF7 protected against lethal sepsis and endotoxemia by down-regulating macrophage pro-inflammatory cytokines and suppressing inflammation-induced organ damage. Taken together, our findings reveal a negatively regulatory role of SLAMF7 in polymicrobial sepsis, which provides sights into the treatment of sepsis.
Authors
Yongjian Wu, Qiaohua Wang, Miao Li, Juanfeng Lao, Huishu Tang, Siqi Ming, Minhao Wu, Sitang Gong, Linhai Li, Lei Liu, Xi Huang
Abstract
The alternative sigma factor RpoS in Borrelia burgdorferi (Bb), the Lyme disease pathogen, is responsible for programmatic positive and negative gene regulation essential for the spirochete’s dual-host enzootic cycle. RpoS is expressed during tick-to-mammal transmission and throughout mammalian infection. Although the mammalian-phase RpoS regulon is well described, its counterpart during the transmission blood meal is unknown. Here, we used Bb-specific transcript enrichment by TBDCapSeq to compare the transcriptomes of wild-type and ΔrpoS Bb in engorged nymphs and following mammalian host-adaptation within dialysis membrane chambers. TBDCapSeq revealed dramatic changes in the contours of the RpoS regulon within ticks and mammals and further confirmed that RpoS-mediated repression is specific to the mammalian-phase of Bb’s enzootic cycle. We also provide evidence that RpoS-dependent gene regulation, including repression of tick-phase genes, is required for persistence in mice. Comparative transcriptomics of engineered Bb strains revealed that BosR, a non-canonical Fur family regulator, and the c-di-GMP effector PlzA reciprocally regulate RpoS function. BosR is required for RpoS-mediated transcription activation and repression in addition to its well-defined role promoting RpoN-dependent transcription of rpoS. During transmission, liganded-PlzA antagonizes RpoS-mediated repression, presumably acting through BosR.
Authors
André A. Grassmann, Rafal Tokarz, Caroline Golino, Melissa A. McLain, Ashley M. Groshong, Justin D. Radolf, Melissa J. Caimano
Abstract
BACKGROUND. To date, only limited data is available on the mechanisms of protection against colonization with Bordetella pertussis in humans. METHODS. In this study, the cellular responses to Bordetella pertussis challenge were monitored longitudinally using high-dimensional EuroFlow-based flow cytometry, allowing quantitative detection of >250 different immune cell subsets in the blood of 15 healthy donors. RESULTS. Participants who were protected against colonization showed different early cellular responses compared to colonized participants. Especially prominent for colonization-protected participants were the early expansion of (CD36-) non classical monocytes at day 1 (d1), Natural Killer cells (d3), follicular T helper cells (d1-d3) and plasma cells (d3). Plasma cell expansion at d3 correlated negatively with the CFU load at d7 and d9 post-challenge. Increased plasma cell maturation at d11-14 was found in participants with seroconversion. CONCLUSION. These early cellular immune responses following experimental infection can now be further characterized and potentially linked to an efficient mucosal immune response, preventing colonization. Ultimately, their presence may be used to evaluate whether new Bordetella pertussis vaccine candidates are protective against Bordetella pertussis colonization, e.g., by bacterial challenge post-vaccination. TRIAL REGISTRATION. NCT03751514. FUNDING. This study is part of the PERISCOPE Project, which has received funding from the Innovative Medicines Initiative 2 Joint Undertaking under grant agreement No 115910. The flow cytometric studies were supported by the EuroFlow Consortium.
Authors
Annieck M. Diks, Hans de Graaf, Cristina Teodosio, Rick J. Groenland, Bas de Mooij, Muktar Ibrahim, Alison R. Hill, Robert C. Read, Jacques J.M. van Dongen, Magdalena A. Berkowska
Abstract
Control of intracellular parasites responsible for malaria requires host IFN-γ+T-bet+CD4+ T cells (Th1 cells) with IL-10 produced by Th1 cells to mitigate the pathology induced by this inflammatory response. However, these IL-10–producing Th1 (induced type I regulatory [Tr1]) cells can also promote parasite persistence or impair immunity to reinfection or vaccination. Here, we identified molecular and phenotypic signatures that distinguished IL-10–Th1 cells from IL-10+Tr1 cells in Plasmodium falciparum–infected people who participated in controlled human malaria infection studies, as well as C57BL/6 mice with experimental malaria caused by P. berghei ANKA. We also identified a conserved Tr1 cell molecular signature shared between patients with malaria, dengue, and graft-versus-host disease. Genetic manipulation of primary human CD4+ T cells showed that the transcription factor cMAF played an important role in the induction of IL-10, while BLIMP-1 promoted the development of human CD4+ T cells expressing multiple coinhibitory receptors. We also describe heterogeneity of Tr1 cell coinhibitory receptor expression that has implications for targeting these molecules for clinical advantage during infection. Overall, this work provides insights into CD4+ T cell development during malaria that offer opportunities for creation of strategies to modulate CD4+ T cell functions and improve antiparasitic immunity.
Authors
Chelsea L. Edwards, Susanna S. Ng, Fabian de Labastida Rivera, Dillon Corvino, Jessica A. Engel, Marcela Montes de Oca, Luzia Bukali, Teija C.M. Frame, Patrick T. Bunn, Shashi Bhushan Chauhan, Siddharth Sankar Singh, Yulin Wang, Jinrui Na, Fiona H. Amante, Jessica R. Loughland, Megan S.F. Soon, Nicola Waddell, Pamela Mukhopadhay, Lambros T. Koufariotis, Rebecca L. Johnston, Jason S. Lee, Rachel Kuns, Ping Zhang, Michelle J. Boyle, Geoffrey R. Hill, James S. McCarthy, Rajiv Kumar, Christian R. Engwerda
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ISSN: 0021-9738 (print), 1558-8238 (online)