The recently completed HIV prevention trials network study 052 is a landmark collaboration demonstrating that HIV transmission in discordant couples can be dramatically reduced by treating the infected individual with antiretroviral therapy (ART). However, the cellular and virological events that occur in the female reproductive tract (FRT) during ART that result in such a drastic decrease in transmission were not studied and remain unknown. Here, we implemented an in vivo model of ART in BM/liver/thymus (BLT) humanized mice in order to better understand the ability of ART to prevent secondary HIV transmission. We demonstrated that the entire FRT of BLT mice is reconstituted with human CD4+ cells that are shed into cervicovaginal secretions (CVS). A high percentage of the CD4+ T cells in the FRT and CVS expressed CCR5 and therefore are potential HIV target cells. Infection with HIV increased the numbers of CD4+ and CD8+ T cells in CVS of BLT mice. Furthermore, HIV was present in CVS during infection. Finally, we evaluated the effect of ART on HIV levels in the FRT and CVS and demonstrated that ART can efficiently suppress cell-free HIV-RNA in CVS, despite residual levels of HIV-RNA+ cells in both the FRT and CVS.
Rikke Olesen, Michael D. Swanson, Martina Kovarova, Tomonori Nochi, Morgan Chateau, Jenna B. Honeycutt, Julie M. Long, Paul W. Denton, Michael G. Hudgens, Amy Richardson, Martin Tolstrup, Lars Østergaard, Angela Wahl, J. Victor Garcia
Melanoma prognosis is dictated by tumor-infiltrating lymphocytes, the migratory and functional behavior of which is guided by chemokine or cytokine gradients. Here, we retrospectively analyzed the expression patterns of 9 homing receptors (CCR/CXCR) in naive and memory CD4+ and CD8+ T lymphocytes in 57 patients with metastatic melanoma (MMel) with various sites of metastases to evaluate whether T cell CCR/CXCR expression correlates with intratumoral accumulation, metastatic progression, and/or overall survival (OS). Homing receptor expression on lymphocytes strongly correlated with MMel dissemination. Loss of CCR6 or CXCR3, but not cutaneous lymphocyte antigen (CLA), on circulating T cell subsets was associated with skin or lymph node metastases, loss of CXCR4, CXCR5, and CCR9 corresponded with lung involvement, and a rise in CCR10 or CD103 was associated with widespread dissemination. High frequencies of CD8
Nicolas Jacquelot, David P. Enot, Caroline Flament, Nadège Vimond, Carolin Blattner, Jonathan M. Pitt, Takahiro Yamazaki, María Paula Roberti, Romain Daillère, Marie Vétizou, Vichnou Poirier-Colame, Michaëla Semeraro, Anne Caignard, Craig L. Slingluff Jr., Federica Sallusto, Sylvie Rusakiewicz, Benjamin Weide, Aurélien Marabelle, Holbrook Kohrt, Stéphane Dalle, Andréa Cavalcanti, Guido Kroemer, Anna Maria Di Giacomo, Michele Maio, Phillip Wong, Jianda Yuan, Jedd Wolchok, Viktor Umansky, Alexander Eggermont, Laurence Zitvogel
Raymond P. Najjar, Jamie M. Zeitzer
The ascending thoracic aorta is designed to withstand biomechanical forces from pulsatile blood. Thoracic aortic aneurysms and acute aortic dissections (TAADs) occur as a result of genetically triggered defects in aortic structure and a dysfunctional response to these forces. Here, we describe mutations in the forkhead transcription factor
Shao-Qing Kuang, Olga Medina-Martinez, Dong-chuan Guo, Limin Gong, Ellen S. Regalado, Corey L. Reynolds, Catherine Boileau, Guillaume Jondeau, Siddharth K. Prakash, Callie S. Kwartler, Lawrence Yang Zhu, Andrew M. Peters, Xue-Yan Duan, National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions (GenTAC) Investigators, National Heart, Lung, and Blood Institute (NHLBI) Grand Opportunity (GO) Exome Sequencing Project (ESP), Michael J. Bamshad, Jay Shendure, Debbie A. Nickerson, Regie L. Santos-Cortez, Xiurong Dong, Suzanne M. Leal, Mark W. Majesky, Eric C. Swindell, Milan Jamrich, Dianna M. Milewicz
T regulatory cells (Tregs) control immune homeostasis by preventing inappropriate responses to self and nonharmful foreign antigens. Tregs use multiple mechanisms to control immune responses, all of which require these cells to be near their targets of suppression; however, it is not known how Treg-to-target proximity is controlled. Here, we found that Tregs attract CD4+ and CD8+ T cells by producing chemokines. Specifically, Tregs produced both CCL3 and CCL4 in response to stimulation, and production of these chemokines was critical for migration of target T cells, as Tregs from
Scott J. Patterson, Anne M. Pesenacker, Adele Y. Wang, Jana Gillies, Majid Mojibian, Kim Morishita, Rusung Tan, Timothy J. Kieffer, C. Bruce Verchere, Constadina Panagiotopoulos, Megan K. Levings
Selenium is a trace element that is essential for human health and is incorporated into more than 25 human selenocysteine-containing (Sec-containing) proteins via unique Sec-insertion machinery that includes a specific, nuclear genome–encoded, transfer RNA (tRNA[Ser]Sec). Here, we have identified a human tRNA[Ser]Sec mutation in a proband who presented with a variety of symptoms, including abdominal pain, fatigue, muscle weakness, and low plasma levels of selenium. This mutation resulted in a marked reduction in expression of stress-related, but not housekeeping, selenoproteins. Evaluation of primary cells from the homozygous proband and a heterozygous parent indicated that the observed deficit in stress-related selenoprotein production is likely mediated by reduced expression and diminished 2′-O-methylribosylation at uridine 34 in mutant tRNA[Ser]Sec. Moreover, this methylribosylation defect was restored by cellular complementation with normal tRNA[Ser]Sec. This study identifies a tRNA mutation that selectively impairs synthesis of stress-related selenoproteins and demonstrates the importance of tRNA modification for normal selenoprotein synthesis.
Erik Schoenmakers, Bradley Carlson, Maura Agostini, Carla Moran, Odelia Rajanayagam, Elena Bochukova, Ryuta Tobe, Rachel Peat, Evelien Gevers, Francesco Muntoni, Pascale Guicheney, Nadia Schoenmakers, Sadaf Farooqi, Greta Lyons, Dolph Hatfield, Krishna Chatterjee
Abnormal fibroblast function underlies poor wound healing in patients with diabetes; however, the mechanisms that impair wound healing are poorly defined. Here, we evaluated fibroblasts from individuals who had type 1 diabetes (T1D) for 50 years or more (Medalists,
Mogher Khamaisi, Sayaka Katagiri, Hillary Keenan, Kyoungmin Park, Yasutaka Maeda, Qian Li, Weier Qi, Thomas Thomou, Danielle Eschuk, Ana Tellechea, Aris Veves, Chenyu Huang, Dennis Paul Orgill, Amy Wagers, George L. King
In successful cancer immunotherapy, T cell responses appear to be directed toward neoantigens created by somatic mutations; however, direct evidence that neoantigen-specific T cells cause regression of established cancer is lacking. Here, we generated T cells expressing a mutation-specific transgenic T cell receptor (TCR) to target different immunogenic mutations in cyclin-dependent kinase 4 (CDK4) that naturally occur in human melanoma. Two mutant CDK4 isoforms (R24C, R24L) similarly stimulated T cell responses in vitro and were analyzed as therapeutic targets for TCR gene therapy. In a syngeneic HLA-A2–transgenic mouse model of large established tumors, we found that both mutations differed dramatically as targets for TCR-modified T cells in vivo. While T cells expanded efficiently and produced IFN-γ in response to R24L, R24C failed to induce an effective antitumor response. Such differences in neoantigen quality might explain why cancer immunotherapy induces tumor regression in some individuals, while others do not respond, despite similar mutational load. We confirmed the validity of the in vivo model by showing that the melan-A–specific (MART-1–specific) TCR DMF5 induces rejection of tumors expressing analog, but not native, MART-1 epitopes. The described model allows identification of those neoantigens in human cancer that serve as suitable T cell targets and may help to predict clinical efficacy.
Matthias Leisegang, Thomas Kammertoens, Wolfgang Uckert, Thomas Blankenstein
Nonalcoholic steatohepatitis (NASH) is the most common liver disease in industrialized countries. NASH is a progressive disease that can lead to cirrhosis, cancer, and death, and there are currently no approved therapies. The development of NASH in animal models requires intact TLR9, but how the TLR9 pathway is activated in NASH is not clear. Our objectives in this study were to identify NASH-associated ligands for TLR9, establish the cellular requirement for TLR9, and evaluate the role of obesity-induced changes in TLR9 pathway activation. We demonstrated that plasma from mice and patients with NASH contains high levels of mitochondrial DNA (mtDNA) and intact mitochondria and has the ability to activate TLR9. Most of the plasma mtDNA was contained in microparticles (MPs) of hepatocyte origin, and removal of these MPs from plasma resulted in a substantial decrease in TLR9 activation capacity. In mice, NASH development in response to a high-fat diet required TLR9 on lysozyme-expressing cells, and a clinically applicable TLR9 antagonist blocked the development of NASH when given prophylactically and therapeutically. These data demonstrate that activation of the TLR9 pathway provides a link between the key metabolic and inflammatory phenotypes in NASH.
Irma Garcia-Martinez, Nicola Santoro, Yonglin Chen, Rafaz Hoque, Xinshou Ouyang, Sonia Caprio, Mark J. Shlomchik, Robert Lee Coffman, Albert Candia, Wajahat Zafar Mehal
The transcription factor GATA3 is essential for the genesis and maturation of the T cell lineage, and GATA3 dysregulation has pathological consequences. Previous studies have shown that GATA3 function in T cell development is regulated by multiple signaling pathways and that the Notch nuclear effector, RBP-J, binds specifically to the
Sakie Ohmura, Seiya Mizuno, Hisashi Oishi, Chia-Jui Ku, Mary Hermann, Tomonori Hosoya, Satoru Takahashi, James Douglas Engel
Cystic fibrosis (CF) disrupts respiratory host defenses, allowing bacterial infection, inflammation, and mucus accumulation to progressively destroy the lungs. Our previous studies revealed that mucus with abnormal behavior impaired mucociliary transport in newborn CF piglets prior to the onset of secondary manifestations. To further investigate mucus abnormalities, here we studied airway surface liquid (ASL) collected from newborn piglets and ASL on cultured airway epithelia. Fluorescence recovery after photobleaching revealed that the viscosity of CF ASL was increased relative to that of non-CF ASL. CF ASL had a reduced pH, which was necessary and sufficient for genotype-dependent viscosity differences. The increased viscosity of CF ASL was not explained by pH-independent changes in HCO3– concentration, altered glycosylation, additional pH-induced disulfide bond formation, increased percentage of nonvolatile material, or increased sulfation. Treating acidic ASL with hypertonic saline or heparin largely reversed the increased viscosity, suggesting that acidic pH influences mucin electrostatic interactions. These findings link loss of cystic fibrosis transmembrane conductance regulator–dependent alkalinization to abnormal CF ASL. In addition, we found that increasing Ca2+ concentrations elevated ASL viscosity, in part, independently of pH. The results suggest that increasing pH, reducing Ca2+ concentration, and/or altering electrostatic interactions in ASL might benefit early CF.
Xiao Xiao Tang, Lynda S. Ostedgaard, Mark J. Hoegger, Thomas O. Moninger, Philip H. Karp, James D. McMenimen, Biswa Choudhury, Ajit Varki, David A. Stoltz, Michael J. Welsh
The development of the hematopoietic system is a dynamic process that is controlled by the interplay between transcriptional and epigenetic networks to determine cellular identity. These networks are critical for lineage specification and are frequently dysregulated in leukemias. Here, we identified histone demethylase KDM2B as a critical regulator of definitive hematopoiesis and lineage commitment of murine hematopoietic stem and progenitor cells (HSPCs). RNA sequencing of
Jaclyn Andricovich, Yan Kai, Weiqun Peng, Adlen Foudi, Alexandros Tzatsos