A therapeutic HBV vaccine containing a checkpoint modifier enhances CD8+ T cell and antiviral responses

• Text
• PDF

Abstract

In patients who progress from acute hepatitis B virus (HBV) infection to a chronic HBV (CHB) infection, CD8+ T cells fail to eliminate the virus and become impaired. A functional cure of CHB likely requires new and highly functional CD8+ T cell responses different from those induced by the infection. Here we report preclinical immunogenicity and efficacy of an HBV therapeutic vaccine that includes herpes simplex virus (HSV) glycoprotein D (gD), a checkpoint modifier of early T cell activation, that enhances, broadens, and prolongs CD8+ T cell responses. We developed a therapeutic HBV vaccine based on a chimpanzee adenovirus serotype 6 (AdC6) vector, called AdC6-gDHBV2, that targets conserved and highly immunogenic regions of the viral polymerase (pol) and core antigens fused into HSV gD. The vaccine was tested with, and without gD, in mice for immunogenicity and in an adeno-associated virus (AAV)8-1.3HBV vector model for antiviral efficacy. The vaccine encoding the HBV antigens within gD stimulates potent and broad CD8+ T cell responses. In a surrogate model of HBV infection, a single intramuscular (i.m.) injection of AdC6-gDHBV2 achieved significant and sustained declines of circulating HBV DNA copies (cps) and HBV surface antigen (HBsAg); both inversely correlated with HBV specific CD8+ T cell frequencies in spleens and livers. AdC6-gDHBV2 is the first therapeutic vaccine to show significant reductions in levels of HBV genome copies and HBsAg when used alone, even when vaccination was delayed for months from infection.

Authors

Mohadeseh Hasanpourghadi, Mikhail Novikov, Robert Ambrose, Arezki Chekaoui, Dakota Newman, Zhiquan Xiang, Andrew D. Luber, Sue L. Currie, XiangYang Zhou, Hildegund C. Ertl

Glymphatic influx and clearance are perturbed in Huntington’s disease

• Text
• PDF

Abstract

The accumulation of mutant huntingtin protein aggregates in neurons is a pathological hallmark of Huntington’s disease (HD). The glymphatic system, a brain-wide perivascular network, facilitates the exchange of interstitial fluid (ISF) and cerebrospinal fluid (CSF), supporting interstitial solute clearance of brain wastes. In this study, we employed dynamic glucose-enhanced (DGE) MRI to measure D-glucose clearance from CSF as a tool to predict glymphatic function in a mouse model of HD. We found significantly diminished CSF clearance efficiency in HD mice prior to phenotypic onset. The impairment of CSF clearance efficiency worsened with disease progression. These DGE MRI findings in compromised glymphatic function were further confirmed with fluorescence-based imaging of CSF tracer influx, suggesting an impaired glymphatic function in premanifest HD. Moreover, expression of the astroglial water channel aquaporin-4 (AQP4) in the perivascular compartment, a key mediator of glymphatic function, was significantly diminished in both HD mouse brain and human HD brain. Our data, acquired using a clinically translatable MRI, indicate a perturbed glymphatic network in the HD brain. Further validation of these findings in clinical studies will provide insights into the potential of glymphatic clearance as a therapeutic target as well as an early biomarker in HD.

Authors

Hongshuai Liu, Lin Chen, Chuangchuang Zhang, Chang Liu, Yuguo Li, Liam Cheng, Yuxiao Ouyang, Catherine Rutledge, John Anderson, Zhiliang Wei, Ziqin Zhang, Hanzhang Lu, Peter C.M. Van Zijl, Jeffrey J. Iliff, Jiadi Xu, Wenzhen Duan

Deconvolution of the tumor-educated platelet transcriptome reveals activated platelet and inflammatory cell transcript signatures

• Text
• PDF

Abstract

Tumor-educated platelets (TEPs) are a potential method of liquid biopsy for the diagnosis and monitoring of cancer. However, the mechanism underlying tumor education of platelets is not known, and transcripts associated with TEPs are often not tumor-associated transcripts. We demonstrated that direct tumor transfer of transcripts to circulating platelets is an unlikely source of the TEP signal. We used CDSeq, a latent Dirichlet allocation algorithm, to deconvolute the TEP signal in blood samples from patients with glioblastoma. We demonstrated that a substantial proportion of transcripts in the platelet transcriptome are derived from non-platelet cells, and the use of this algorithm allows the removal of contaminant transcripts. Furthermore, we used the results of this algorithm to demonstrate that TEPs represent a subset of more activated platelets, which also contain transcripts normally associated with non-platelet inflammatory cells, suggesting that these inflammatory cells, possibly in the tumor microenvironment, transfer transcripts to platelets that are then found in circulation. Our analysis suggests a useful and efficient method of processing TEP transcriptomic data to enable the isolation of a unique TEP signal associated with specific tumors.

Authors

Jerome M. Karp, Aram S. Modrek, Ravesanker Ezhilarasan, Ze-Yan Zhang, Yingwen Ding, Melanie Graciani, Ali Sahimi, Michele Silvestro, Ting Chen, Shuai Li, Kwok-Kin Wong, Bhama Ramkhelawon, Krishna P.L. Bhat, Erik P. Sulman

Immune perturbation following SHIV infection is greater in newborn macaques than in infants

• Text
• PDF

Abstract

Transmission of HIV-1 to newborns and infants remains high, with 130,000 new infections in 2022 in resource poor settings. Half of HIV-infected newborns, if untreated, progress to disease and death within 2 years. While immunologic immaturity likely promotes pathogenesis and poor viral control, little is known about immune damage in newborns and infants. Here we examined pathologic, virologic, and immunologic outcomes in rhesus macaques exposed to pathogenic SHIV at 1-2 weeks, defined as newborns, or at 4 months of age, considered infants. Kinetics of plasma viremia and lymph node seeding DNA were indistinguishable in newborns and infants, but levels of viral DNA in gut and lymphoid tissues 6-10 weeks post-infection were significantly higher in newborns versus either infant or adult macques. Two of six newborns with the highest viral seeding required euthanasia at 25 days. We observed age-dependent alterations in leukocyte subsets and gene expression. Compared with infants, newborns had stronger skewing of monocytes and CD8+ T cells toward differentiated subsets and little evidence of type I interferon responses by transcriptomic analyses. Thus, SHIV infection reveals distinct immunological alterations in newborn and infant macaques. These studies lay the groundwork for understanding how immune maturation affects pathogenesis in pediatric HIV-1 infection.

Authors

Mariya B. Shapiro, Tracy Ordonez, Shilpi Pandey, Eisa Mahyari, Kosiso Onwuzu, Jason Reed, Heather Sidener, Jeremy Smedley, Lois M. Colgin, Amanda Johnson, Anne D. Lewis, Benjamin Bimber, Jonah B. Sacha, Ann J. Hessell, Nancy L. Haigwood

miR-33 deletion in hepatocytes attenuates NAFLD-NASH-HCC progression

• Text
• PDF

Abstract

The complexity of the mechanisms underlying non-alcoholic fatty liver disease (NAFLD) progression remains a significant challenge for the development of effective therapeutics. miRNAs have shown great promise as regulators of biological processes and as therapeutic targets for complex diseases. Here, we study the role of hepatic miR-33, an important regulator of lipid metabolism, during the progression of NAFLD and the development of hepatocellular carcinoma (HCC). We report that miR-33 is elevated in the livers of humans and mice with NAFLD and that its deletion in hepatocytes (miR-33 HKO) improves multiple aspects of the disease, including steatosis and inflammation, limiting the progression to non-alcoholic steatohepatitis (NASH), fibrosis and HCC. Mechanistically, hepatic miR-33 deletion reduces lipid synthesis and promotes mitochondrial fatty acid oxidation, reducing lipid burden. Additionally, absence of miR-33 alters the expression of several known miR-33 target genes involved in metabolism and results in improved mitochondrial function and reduced oxidative stress. The reduction in lipid accumulation and liver injury resulted in decreased YAP/TAZ pathway activation, which may be involved in the reduced HCC progression in HKO livers. Together, these results suggest suppressing hepatic miR-33 may be an effective therapeutic approach to temper the development of NAFLD, NASH, and HCC in obesity

Authors

Pablo Fernández-Tussy, Magdalena P. Cardelo, Hanming Zhang, Jonathan Sun, Nathan L. Price, Nabil E. Boutagy, Leigh Goedeke, Martí Cadena-Sandoval, Chrysovalantou E. Xirouchaki, Wendy A. Brown, Xiaoyong Yang, Oscar Pastor-Rojo, Rebecca A. Haeusler, Anton M. Bennett, Tony Tiganis, Yajaira Suárez, Carlos Fernández-Hernando

CXCL9, CXCL10, and CCL19 synergistically recruit T-lymphocytes to skin in lichen planus

• Text
• PDF

Abstract

Lichen planus (LP) is a chronic, debilitating, inflammatory disease of the skin and mucous membranes that affects 1% to 2% of Americans. Its molecular pathogenesis remains poorly understood, and there are no FDA-approved treatments. We performed single cell RNA sequencing on paired blood and skin samples (lesional and non-lesional tissue) from 7 LP patients. We discovered that LP keratinocytes and fibroblasts specifically secrete a combination of CXCL9, CXCL10, and CCL19 cytokines. Using an in vitro migration assay with primary human T cells, we demonstrated that CCL19 in combination with either cytokine synergistically enhanced recruitment of CD8 T cells, more than the sum of individual cytokines. Moreover, exhausted T cells in lesional LP skin secreted CXCL13, which along with CCL19 also enhanced recruitment of T cells, suggesting a feed-forward loop in LP. Finally, LP blood revealed decreased circulating naïve CD8 T cells compared to healthy volunteers, consistent with recruitment to skin. Molecular analysis of LP skin and blood samples increased our understanding of disease pathogenesis and identified CCL19 as a new therapeutic target for treatment.

Authors

Anna E. Kersh, Satish Sati, Jianhe Huang, Christina Murphy, Olivia C. Ahart, Thomas H. Leung

Hidden hearing loss in a Charcot-Marie-Tooth type 1A mouse model

• Text
• PDF

Abstract

Hidden hearing loss (HHL), a recently described auditory neuropathy characterized by normal audiometric thresholds but reduced sound-evoked cochlear compound action potentials, has been proposed to contribute to hearing difficulty in noisy environments in people with normal hearing thresholds, a widespread complaint. While most studies on HHL pathogenesis have focused on inner hair cell (IHC) synaptopathy, we recently showed that transient auditory nerve (AN) demyelination also causes HHL in mice. To test the impact of myelinopathy on hearing in a clinically relevant model, we studied a mouse model of Charcot-Marie-Tooth type 1A (CMT1A), the most prevalent hereditary peripheral neuropathy in humans. CMT1A mice exhibit the functional hallmarks of HHL together with disorganization of AN heminodes near the IHCs with minor loss of AN fibers. These results support the hypothesis that mild disruptions of AN myelination can cause HHL, and that heminodal defects contribute to the alterations in the sound-evoked cochlear compound action potentials seen in this mouse model. Also, these findings suggest that patients with CMT1A or other mild peripheral neuropathies are likely to suffer from HHL. Furthermore, these results suggest that studies of hearing in CMT1A patients might help develop robust clinical tests for HHL, which are currently lacking.

Authors

Luis R. Cassinotti, Lingchao Ji, M. Caroline Yuk, Aditi S. Desai, Nathan D. Cass, Zahara A. Amir, Gabriel Corfas

MerTK-dependent efferocytosis by monocytic-MDSCs mediates resolution of post-lung transplant ischemia-reperfusion injury

• Text
• PDF

Abstract

Lung transplantation (LTx) outcomes are impeded by ischemia-reperfusion injury (IRI) and subsequent chronic lung allograft dysfunction (CLAD). We examined the undefined role of MerTK (receptor Mer tyrosine kinase) on monocytic myeloid-derived suppressor cells (M-MDSCs) in efferocytosis to facilitate resolution of lung IRI. Single-cell RNA sequencing of lung tissue and bronchoalveolar lavage (BAL) from post-LTx patients were analyzed. Murine lung hilar ligation and allogeneic orthotopic LTx models of IRI were used with Balb/c (WT), Cebpb-/- (MDSC-deficient), Mertk-/- or MerTK-CR (cleavage resistant) mice. A significant downregulation in MerTK-related efferocytosis genes in M-MDSC populations of CLAD patients was observed compared to healthy subjects. In the murine IRI model, significant increase in M-MDSCs, MerTK expression, efferocytosis and attenuation of lung dysfunction was observed in WT mice during injury resolution that was absent in Cebpb-/- and Mertk-/- mice. Adoptive transfer of M-MDSCs in Cebpb-/- mice significantly attenuated lung dysfunction and inflammation. Additionally, in a murine orthotopic LTx model, increases in M-MDSCs were associated with resolution of lung IRI in the transplant recipients. In vitro studies demonstrated the ability of M-MDSCs to efferocytose apoptotic neutrophils in a MerTK-dependent manner. Our results suggest that MerTK-dependent efferocytosis by M-MDSCs can substantially contribute to the resolution of post-LTx IRI.

Authors

Victoria Leroy, Denny Joseph Manual Kollareth, Zhenxiao Tu, Jeff Arni C. Valisno, Makena Woolet-Stockton, Biplab K. Saha, Amir M. Emtiazjoo, Mindaugas Rackauskas, Lyle L. Moldawer, Philip A. Efron, Guoshuai Cai, Carl Atkinson, Gilbert R. Upchurch, Jr., Ashish K. Sharma

Hypoxia-induced complement component 3 promotes aggressive tumor growth in the glioblastoma microenvironment

• Text
• PDF

Abstract

Glioblastoma (GBM) is the most aggressive form of glioma with a high rate of relapse despite intensive treatment. Tumor recurrence is tightly linked to radio-resistance, which in turn is associated with hypoxia. Here, we discovered a strong link between hypoxia and local complement signaling using publicly available bulk, single cell, and spatially resolved transcriptomic data from human GBM patients. Complement component 3 (C3) and the receptor C3AR1 were both associated with aggressive disease and shorter survival in human glioma. In a genetically engineered mouse model of GBM, we found C3 specifically in hypoxic tumor areas. In vitro, we found an oxygen level-dependent increase in C3 and C3AR1 expression in response to hypoxia in several GBM and stromal cell types. C3a induced M2 polarization of cultured microglia and macrophages in a C3aR-dependent fashion. Targeting C3aR using the antagonist SB290157 prolonged survival of glioma bearing mice both alone and in combination with radiotherapy while reducing the number of M2-polarized macrophages. Our findings establish a strong link between hypoxia and complement pathways in GBM, and support a role of hypoxia-induced C3a-C3aR signaling as a contributor to glioma aggressiveness by regulating macrophage polarization.

Authors

Rebecca Rosberg, Karolina I. Smolag, Jonas Sjölund, Elinn Johansson, Christina Bergelin, Julia Wahldén, Vasiliki Pantazopoulou, Crister Ceberg, Kristian Pietras, Anna M. Blom, Alexander Pietras

dldh^cri3 zebrafish exhibited altered mitochondrial ultrastructure, morphology and dysfunction partially rescued by probucol or thiamine

• Text
• PDF

Abstract

Dihydrolipoamide dehydrogenase (DLD) deficiency is a recessive mitochondrial disease caused by variants in DLD, the E3 subunit of mitochondrial α-keto acid dehydrogenase complexes. DLD disease symptoms are multi-systemic, variably manifesting as Leigh syndrome, neurodevelopmental disability, seizures, cardiomyopathy, liver disease, fatigue and lactic acidemia. While most DLD disease symptoms are attributed to dysfunction of the pyruvate dehydrogenase complex, understanding the effects of other α-keto acid dehydrogenase deficiencies remain unclear. Current therapies for DLD deficiency are ineffective, with no vertebrate animal model available for preclinical study. We created a viable Danio rerio (zebrafish) KO model of DLD deficiency, dldhcri3. Detailed phenotypic characterization revealed shortened larval survival, uninflated swim bladder, hepatomegaly and fatty liver, and reduced swim activity. These animals displayed increased pyruvate and lactate levels, with severe disruption of branched-chain amino acid catabolism manifest as increased valine, leucine, isoleucine, α-ketoisovalerate, and α-ketoglutarate levels. Evaluation of mitochondrial ultrastructure revealed gross enlargement, severe cristae disruption and reduction in matrix electron density in liver, intestines, and muscle. Therapeutic modeling of candidate therapies demonstrated probucol or thiamine improved larval swim activity. Overall, this vertebrate model demonstrated characteristic phenotypic and metabolic alterations of DLD disease, offering a robust platform to screen and characterize candidate therapies.

Authors

Manuela Lavorato, Donna Iadarola, Cristina Remes, Prabhjot Kaur, Chynna Broxton, Neal D. Mathew, Rui Xiao, Christoph Seiler, Eiko Nakamaru-Ogiso, Vernon E. Anderson, Marni J. Falk