Therapeutics
Abstract
Ischemic stroke is a predominant cause of disability worldwide, with thrombolytic or mechanical removal of the occlusion being the only therapeutic option. Reperfusion bears the risk of an acute deleterious calcium-dependent breakdown of the blood-brain barrier. Its mechanism, however, is unknown. Here, we identified type 5 NADPH oxidase (NOX5), a calcium-activated, ROS-forming enzyme, as the missing link. Using a humanized knockin (KI) mouse model and in vitro organotypic cultures, we found that reoxygenation or calcium overload increased brain ROS levels in a NOX5-dependent manner. In vivo, postischemic ROS formation, infarct volume, and functional outcomes were worsened in NOX5-KI mice. Of clinical and therapeutic relevance, in a human blood-barrier model, pharmacological NOX inhibition also prevented acute reoxygenation-induced leakage. Our data support further evaluation of poststroke recanalization in the presence of NOX inhibition for limiting stroke-induced damage.
Authors
Ana I. Casas, Pamela W.M. Kleikers, Eva Geuss, Friederike Langhauser, Thure Adler, Dirk H. Busch, Valerie Gailus-Durner, Martin Hrabê de Angelis, Javier Egea, Manuela G. Lopez, Christoph Kleinschnitz, Harald H.H.W. Schmidt
Abstract
The cytoplasmic aggregation of TDP-43 is a hallmark of degenerating neurons in amyotrophic lateral sclerosis (ALS) and subsets of frontotemporal dementia (FTD). In order to reduce TDP-43 pathology, we have generated single chain (scFv) antibodies against the RNA recognition motif 1 (RRM1) of TDP-43 which is involved in abnormal protein self-aggregation and interaction with p65 nuclear factor kappa B (NFKB). Viral-mediated delivery into the nervous system of a scFv antibody, named VH7Vk9, reduced microgliosis in a mouse model of acute neuroinflammation and it mitigated cognitive impairment, motor defects, TDP-43 proteinopathy and neuroinflammation in transgenic mice expressing ALS-linked TDP-43 mutations. These results suggest that antibodies targeting the RRM1 domain of TDP-43 might provide new therapeutic avenues for treatment of ALS and FTD.
Authors
Silvia Pozzi, Sai Sampath Thammisetty, Philippe Codron, Reza Rahimian, Karine V. Plourde, Geneviève Soucy, Christine Bareil, Daniel Phaneuf, Jasna Kriz, Claude Gravel, Jean-Pierre Julien
Abstract
Allergen immunotherapy for patients with allergies begins with weekly escalating doses of allergen under medial supervision to monitor and treat IgE-mast cell mediated anaphylaxis. There is currently no treatment to safely desensitize mast cells to enable robust allergen immunotherapy with therapeutic levels of allergen. Here we demonstrated that liposomal nanoparticles bearing an allergen and a high-affinity glycan ligand of the inhibitory receptor CD33 profoundly suppressed IgE-mediated activation of mast cells, prevented anaphylaxis in transgenic mice with mast cells expressing human CD33, and desensitized mice from subsequent allergen challenge for several days. We showed that high levels of CD33 were consistently expressed on human skin mast cells, and that the antigenic-liposomes with CD33 ligand prevented IgE-mediated bronchoconstriction in slices of human lung. The results demonstrated the potential of exploiting CD33 to desensitize mast cells to provide a therapeutic window for administering allergen immunotherapy without triggering anaphylaxis.
Authors
Shiteng Duan, Cynthia J. Koziol-White, William F. Jester Jr., Corwin M. Nycholat, Matthew S. Macauley, Reynold A. Panettieri Jr., James C. Paulson
Abstract
BACKGROUND. Awake neurosurgery requires patients to converse and respond to visual or verbal prompts to identify and protect brain tissue supporting essential functions such as language, primary sensory modalities, and motor function. These procedures can be poorly tolerated due to patient anxiety, yet acute anxiolytic medications typically cause sedation and impair cortical function. METHODS. In this study, direct electrical stimulation of the left dorsal anterior cingulum bundle was discovered to reliably evoke positive affect and anxiolysis without sedation in an epilepsy patient undergoing research testing during standard, in-patient intracranial electrode monitoring. These effects were quantified using subjective and objective behavioral measures, and stimulation was found to evoke robust changes in local and distant neural activity. RESULTS. The index patient ultimately required an awake craniotomy procedure to confirm safe resection margins in the treatment of her epilepsy. During the procedure, cingulum bundle stimulation enhanced positive affect and reduced the patient’s anxiety to the point that intravenous anesthetic/anxiolytic medications were discontinued and cognitive testing was completed. Behavioral responses were subsequently replicated in two patients with anatomically similar electrode placements localized to an approximately 1cm span along the anterior dorsal cingulum bundle above genu of the corpus callosum. CONCLUSIONS. The current study demonstrates a robust anxiolytic response to cingulum bundle stimulation in three epilepsy patients. TRIAL REGISTRATION. The current study was not affiliated with any formal clinical trial. FUNDING. This project was supported by the American Foundation for Suicide Prevention and the National Institutes of Health.
Authors
Kelly R. Bijanki, Joseph R. Manns, Cory S. Inman, Ki Sueng Choi, Sahar Harati, Nigel P. Pedersen, Daniel L. Drane, Allison C. Waters, Rebecca E. Fasano, Helen S. Mayberg, Jon T. Willie
Abstract
Immune checkpoint therapies have shown tremendous promise in cancer therapy. However, tools to assess their target engagement, and hence ability to predict their efficacy, have been lacking. Here, we show that target engagement and tumor residence kinetics of antibody therapeutics targeting the programmed death ligand-1 (PD-L1) can be quantified non-invasively. In computational docking studies, we observed that PD-L1-targeted antibodies (atezolizumab, avelumab, durvalumab) and a high affinity PD-L1 binding peptide, WL12, have common interaction sites on PD-L1. Using the peptide radiotracer [64Cu]WL12 in vivo, we employed positron emission tomography (PET) imaging and biodistribution studies, in multiple xenograft models and demonstrated that variable PD-L1 expression and its saturation by atezolizumab, avelumab, and durvalumab can be quantified independent of biophysical properties and pharmacokinetics of antibodies. Next, we used [64Cu]WL12 to evaluate the impact of time and dose on free fraction of tumor PD-L1 levels during treatment. These quantitative measures enabled, by mathematical modeling, prediction of antibody doses needed to achieve therapeutically effective occupancy (defined as >90%). Thus, we show that peptide-based PET is a promising tool for optimizing dose and therapeutic regimens employing PD-L1 checkpoint antibodies, and can be used for improving therapeutic efficacy.
Authors
Dhiraj Kumar, Ala Lisok, Elyes Dahmane, Matthew D. McCoy, Sagar Shelake, Samit Chatterjee, Viola Allaj, Polina Sysa-Shah, Bryan Wharram, Wojciech G. Lesniak, Ellen Tully, Edward Gabrielson, Elizabeth M. Jaffee, John T. Poirier, Charles M. Rudin, Jogarao V.S. Gobburu, Martin G. Pomper, Sridhar Nimmagadda
Abstract
Current thalassemia gene therapy protocols require the collection of hematopoietic stem/progenitor cells (HSPCs), in vitro culture, lentivirus vector transduction, and retransplantation into myelo-ablated patients. Because of cost and technical complexity, it is unlikely that such protocols will be applicable in developing countries where the greatest demand for a beta-thalassemia therapy lies. We have developed a simple in vivo HSPC gene therapy approach that involved HSPC mobilization and an intravenous injection of integrating HDAd5/35++ vectors. Transduced HSPCs homed back to the bone marrow where they persisted long-term. HDAd5/35++ vectors for in vivo gene therapy of thalassemia had a unique capsid that targeted primitive HSPCs through human CD46, a relatively safe SB100X transposase-based integration machinery, a micro-LCR driven gamma-globin gene and, a MGMT(P140K) system that allowed for increasing the therapeutic effect by short-term treatment with low-dose O6BG/BCNU. We showed in “healthy” human CD46 transgenic mice and in a mouse model of thalassemia intermedia that our in vivo approach resulted in stable gamma-globin expression in the majority of circulating red blood cells. The high marking frequency was maintained in secondary recipients. In the thalassemia model, a near complete phenotypic correction was achieved. The treatment was well tolerated. This cost-efficient and “portable” approach could permit a broader clinical application of thalassemia gene therapy.
Authors
Hongjie Wang, Aphrodite Georgakopoulou, Nikoletta Psatha, Chang Li, Chrysi Capsali, Himanshu Bhusan Samal, Achilles Anagnostopoulos, Anja Ehrhardt, Zsuzsanna Izsvák, Thalia Papayannopoulou, Evangelia Yannaki, André Lieber
Abstract
Tumor-associated myeloid cells maintain immunosuppressive microenvironments within tumors. Identification of myeloid-specific receptors to modulate tumor-associated macrophage and myeloid-derived suppressor cell (MDSC) functions remains challenging. The leukocyte immunoglobulin-like receptor B (LILRB) family members are negative regulators of myeloid cell activation. We investigated how LILRB targeting could modulate tumor-associated myeloid cell function. LILRB2 antagonism inhibited receptor-mediated activation of SHP1/2 and enhanced proinflammatory responses. LILRB2 antagonism also inhibited AKT and STAT6 activation in the presence of M-CSF and IL-4. Transcriptome analysis revealed that LILRB2 antagonism altered genes involved in cell cytoskeleton remodeling, lipid/cholesterol metabolism, and endosomal sorting pathways, as well as changed differentiation gene networks associated with inflammatory myeloid cells as opposed to their alternatively activated phenotype. LILRB2 blockade effectively suppressed granulocytic MDSC and Treg infiltration and significantly promoted in vivo antitumor effects of T cell immune checkpoint inhibitors. Furthermore, LILRB2 blockade polarized tumor-infiltrating myeloid cells from non–small cell lung carcinoma tumor tissues toward an inflammatory phenotype. Our studies suggest that LILRB2 can potentially act as a myeloid immune checkpoint by reprogramming tumor-associated myeloid cells and provoking antitumor immunity.
Authors
Hui-Ming Chen, William van der Touw, Yuan Shuo Wang, Kyeongah Kang, Sunny Mai, Jilu Zhang, Dayanira Alsina-Beauchamp, James A. Duty, Sathish Kumar Mungamuri, Bin Zhang, Thomas Moran, Richard Flavell, Stuart Aaronson, Hong-Ming Hu, Hisashi Arase, Suresh Ramanathan, Raja Flores, Ping-Ying Pan, Shu-Hsia Chen
Abstract
Plasmacytoid dendritic cells (pDCs) play a key role in antiviral responses by producing type-1 IFNs. However, recent studies showed that pDCs induce immune suppression and promote tumor growth in human ovarian cancer and myeloma. The molecular mechanisms underlying pDC acquisition of these properties are unknown. Here we show that human pDCs activated by CpG inhibited growth and induced apoptosis in myeloma cells via secreted IFN-α, but direct contact with myeloma cells converted pDCs into tumor-promoting cells by suppressing pDC IFN-α production. E-cadherin, expressed on both myeloma cells and pDCs, mediated these effects via a homophilic interaction — activation of E-cadherin signaling upregulated and activated TNFAIP3 to interact with TLR9, resulting in TLR9 ubiquitination and degradation, and inhibition of IFN-α production in pDCs. These findings were supported by an in vivo study in which pDC depletion induced tumor regression and better survival in the Vk*MYC myeloma mouse model. Furthermore, IFNAR1 expression level positively correlated to overall survival of patients with multiple myeloma (MM), and the IFN-α level in patient bone marrow was significantly lower than that in marrow of healthy individuals. This study reveals a novel mechanism underlying how MM tumors educate pDCs in their microenvironment and provides new targets for improving the treatment of MM.
Authors
Enguang Bi, Rong Li, Laura C. Bover, Haiyan Li, Pan Su, Xingzhe Ma, Chunjian Huang, Qiang Wang, Lintao Liu, Maojie Yang, Zhijuan Lin, Jianfei Qian, Weijun Fu, Yong-Jun Liu, Qing Yi
Abstract
Previous findings showed that in mice, complete knockout of activity-dependent neuroprotective protein (ADNP) abolishes brain formation, while haploinsufficiency (Adnp+/–) causes cognitive impairments. We hypothesized that mutations in ADNP lead to a developmental/autistic syndrome in children. Indeed, recent phenotypic characterization of children harboring ADNP mutations (ADNP syndrome children) revealed global developmental delays and intellectual disabilities, including speech and motor dysfunctions. Mechanistically, ADNP includes a SIP motif embedded in the ADNP-derived snippet, drug candidate NAP (NAPVSIPQ also known as CP201), which binds to microtubule end binding protein 3, essential for dendritic spine formation. Here, we established a unique neuronal membrane tagged green fluorescent protein expressing Adnp+/– mouse line allowing in vivo synaptic pathology quantification. We discovered that Adnp deficiency reduced dendritic spine density and altered synaptic gene expression, both of which were partly ameliorated by NAP treatment. Adnp+/– mice further exhibited global developmental delays, vocalization impediments, gait/motor dysfunctions and social/object memory impairments, all partially reversed by daily NAP administration (systemic/nasal). In conclusion, we now connected ADNP-related synaptic pathology to developmental/behavioral outcomes, establishing NAP in vivo target engagement and identifying potential biomarkers. Together, these studies pave the path toward clinical development of NAP (CP201) in the ADNP syndrome.
Authors
Gal Hacohen-Kleiman, Shlomo Sragovich, Gidon Karmon, Andy Y. L. Gao, Iris Grigg, Metsada Pasmanik-Chor, Albert Le, Vlasta Korenková, R. Anne McKinney, Illana Gozes
Abstract
BACKGROUND. Intravenous immunoglobulin (IVIg), plasma exchange and immunoadsorption are frequently used in the management of severe autoimmune diseases mediated by pathogenic IgG autoantibodies. These approaches to modulate IgG levels can however be associated with some severe adverse reactions and significant burden to patients. Targeting the neonatal Fc receptor (FcRn) presents an innovative and potentially more effective, safer, and convenient alternative for clearing pathogenic IgGs. METHODS. A randomized, double-blind, placebo-controlled first-in-human study was conducted in 62 healthy volunteers to explore single and multiple ascending intravenous doses of the FcRn antagonist efgartigimod. The study objectives were to assess the safety, tolerability, pharmacokinetics, pharmacodynamics, and immunogenicity. The findings of this study were compared with the pharmacodynamics profile elicited by efgartigimod in cynomolgus monkeys. RESULTS. Efgartigimod treatment resulted in a rapid and specific clearance of serum IgG levels in both cynomolgus monkeys and healthy volunteers. In humans, single administration of efgartigimod reduced IgG levels up to 50% whilst multiple dosing further lowered IgGs on average by 75% of baseline levels. Approximately 8 weeks following the last administration, IgG levels returned to baseline. Efgartigimod did not alter the homeostasis of albumin or immunoglobulins other than IgG and no serious adverse events related to efgartigimod infusion were observed. CONCLUSION. Antagonizing FcRn using efgartigimod is safe and results in a specific, profound, and sustained reduction of serum IgG levels. These results warrant further evaluation of this therapeutic approach in IgG-driven autoimmune diseases. TRIAL REGISTRATION. Clinicaltrials.gov NCT03457649. FUNDING. argenx bvba.
Authors
Peter Ulrichts, Antonio Guglietta, Torsten Dreier, Tonke van Bragt, Valérie Hanssens, Erik Hofman, Bernhardt Vankerckhoven, Peter Verheesen, Nicolas Ongenae, Valentina Lykhopiy, F. Javier Enriquez, JunHaeng Cho, Raimund J. Ober, E. Sally Ward, Hans de Haard, Nicolas Leupin
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Copyright © 2019 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)