bioRxiv : the preprint server for biology
Chen, X;Wolfe, DA;Sivadasan Bindu, D;Zhang, M;Taskin, N;Goertsen, D;Shay, TF;Sullivan, E;Huang, SF;Ravindra Kumar, S;Arokiaraj, CM;Plattner, V;Campos, LJ;Mich, J;Monet, D;Ngo, V;Ding, X;Omstead, V;Weed, N;Bishaw, Y;Gore, B;Lein, ES;Akrami, A;Miller, C;Levi, BP;Keller, A;Ting, JT;Fox, AS;Eroglu, C;Gradinaru, V;
PMID: 36711773 | DOI: 10.1101/2023.01.12.523844
Delivering genes to and across the brain vasculature efficiently and specifically across species remains a critical challenge for addressing neurological diseases. We have evolved adeno-associated virus (AAV9) capsids into vectors that transduce brain endothelial cells specifically and efficiently following systemic administration in wild-type mice with diverse genetic backgrounds and rats. These AAVs also exhibit superior transduction of the CNS across non-human primates (marmosets and rhesus macaques), and ex vivo human brain slices although the endothelial tropism is not conserved across species. The capsid modifications translate from AAV9 to other serotypes such as AAV1 and AAV-DJ, enabling serotype switching for sequential AAV administration in mice. We demonstrate that the endothelial specific mouse capsids can be used to genetically engineer the blood-brain barrier by transforming the mouse brain vasculature into a functional biofactory. Vasculature-secreted Hevin (a synaptogenic protein) rescued synaptic deficits in a mouse model.
Silva, C;Picardo, M;Del Negro, C;
| DOI: 10.1096/fasebj.2022.36.S1.R2948
Here we administered Cre-dependent shRNA to knock-down _Scn8a_ (thus Nav1.6) in Cre-expressing glutamatergic neurons in preBötC and quantified mRNA per glutamatergic neuron. We used adult Vglut2Cre mice (10-14 weeks old) and injected 50 nL of AAVs carrying the shRNA. We used _in situ_ hybridization (RNAscope Fluorescent Assay) to label mRNA of _Scn8a_ and to identify transduced glutamatergic neurons in the preBötC for RNA quantification at 2 and 6 weeks after injection. Samples were visualized under the Four-Channel, Upright Confocal Microscope Body Based on Cerna System (ThorLabs), and images were acquired using the ThorImage LS Data Acquisition Software, at 40x magnification. The amount of RNA per cell was quantified using the open-source software Quantitative Pathology(QuPath). We obtained the mean of the number of transcripts per cell ± the standard deviation (SD), and unpaired t-test was used to evaluate the statistical difference between the shRNA injected mice and their control group (mice whose viral vector contained a non-targeting shRNA sequence).
Ramachandran, M;Vaccaro, A;van de Walle, T;Georganaki, M;Lugano, R;Vemuri, K;Kourougkiaouri, D;Vazaios, K;Hedlund, M;Tsaridou, G;Uhrbom, L;Pietilä, I;Martikainen, M;van Hooren, L;Olsson Bontell, T;Jakola, AS;Yu, D;Westermark, B;Essand, M;Dimberg, A;
PMID: 37172581 | DOI: 10.1016/j.ccell.2023.04.010
Glioblastomas are aggressive brain tumors that are largely immunotherapy resistant. This is associated with immunosuppression and a dysfunctional tumor vasculature, which hinder T cell infiltration. LIGHT/TNFSF14 can induce high endothelial venules (HEVs) and tertiary lymphoid structures (TLS), suggesting that its therapeutic expression could promote T cell recruitment. Here, we use a brain endothelial cell-targeted adeno-associated viral (AAV) vector to express LIGHT in the glioma vasculature (AAV-LIGHT). We found that systemic AAV-LIGHT treatment induces tumor-associated HEVs and T cell-rich TLS, prolonging survival in αPD-1-resistant murine glioma. AAV-LIGHT treatment reduces T cell exhaustion and promotes TCF1+CD8+ stem-like T cells, which reside in TLS and intratumoral antigen-presenting niches. Tumor regression upon AAV-LIGHT therapy correlates with tumor-specific cytotoxic/memory T cell responses. Our work reveals that altering vascular phenotype through vessel-targeted expression of LIGHT promotes efficient anti-tumor T cell responses and prolongs survival in glioma. These findings have broader implications for treatment of other immunotherapy-resistant cancers.
Molecular Therapy - Nucleic Acids
Chen, T;Chang, S;Wu, Y;Yen, Y;Hsu, F;Chen, Y;Ming, Y;Hsu, H;Su, Y;Wong, S;Hung, J;Chiou, S;Jong, Y;Chen, J;
| DOI: 10.1016/j.omtn.2023.03.005
Spinal muscular atrophy (SMA) is a neurodegenerative disease characterized by the selective loss of spinal motor neurons (MNs) and concomitant muscle weakness. Mutation of SMN1 is known to cause SMA, and restoring SMN protein levels via antisense oligonucleotide treatment is effective for ameliorating symptoms. However, this approach is hindered by exorbitant costs, invasive procedures, and poor treatment responses of some patients. Here, we seek to circumvent these hurdles by identifying reliable biomarkers that could predict treatment efficacy. We uncovered that MiR34 exhibits consistent downregulation during SMA progression in both human and rodent contexts. Importantly, Mir34 family-knockout mice display axon swelling and reduced neuromuscular junction (NMJ) endplates, recapitulating SMA pathology. Introducing MiR34a via scAAV9 improved the motor ability of SMNΔ7 mice, possibly by restoring NMJ endplate size. Finally, we observed a consistent decreasing trend in MiR34 family expression in the cerebrospinal fluid (CSF) of type I SMA patients during the loading phase of nusinersen treatment. Baseline CSF MiR34 levels before nusinersen injection proved predictive of patient motor skills 1 year later. Thus, we propose that MiR34 may serve as a biomarker of SMA since it is associated with the pathology and can help evaluate the therapeutic effects of nusinersen.
Molecular therapy : the journal of the American Society of Gene Therapy
Butterfield, JSS;Yamada, K;Bertolini, TB;Syed, F;Kumar, SRP;Li, X;Arisa, S;Piñeros, AR;Tapia, A;Rogers, CA;Li, N;Rana, J;Biswas, M;Terhorst, C;Kaufman, RJ;de Jong, YP;Herzog, RW;
PMID: 35821634 | DOI: 10.1016/j.ymthe.2022.07.005
Hepatic adeno-associated viral (AAV) gene transfer has the potential to cure the X-linked bleeding disorder hemophilia A. However, declining therapeutic coagulation factor VIII (FVIII) expression has plagued clinical trials. To assess the mechanistic underpinnings of this loss of FVIII expression, we developed a hemophilia A mouse model that shares key features observed in clinical trials. Following liver-directed AAV8 gene transfer in the presence of rapamycin, initial FVIII protein expression declines over time in the absence of antibody formation. Surprisingly, loss of FVIII protein production occurs despite persistence of transgene and mRNA, suggesting a translational shutdown rather than a loss of transduced hepatocytes. Some of the animals develop ER stress, which may be linked to hepatic inflammatory cytokine expression. FVIII protein expression is preserved by IL-15/IL-15R blockade, which suppresses CD8+ T and NK cell responses. Interestingly, mice with initial FVIII levels >100% of normal had diminishing expression while still under immune suppression. Taken together, our findings of inter-animal variability of the response, and the ability of the immune system to shut down transgene expression without utilizing cytolytic or antibody-mediated mechanisms illustrate the challenges associated with FVIII gene transfer. Our protocols based upon cytokine blockade should help maintaining efficient FVIII expression.
bioRxiv : the preprint server for biology
Hughes, AC;Pollard, BG;Xu, B;Gammons, JW;Chapman, P;Bikoff, JB;Schwarz, LA;
PMID: 36798174 | DOI: 10.1101/2023.02.07.527312
As the discovery of cellular diversity in the brain accelerates, so does the need for functional tools that target cells based on multiple features, such as gene expression and projection target. By selectively driving recombinase expression in a feature-specific manner, one can utilize intersectional strategies to conditionally promote payload expression only where multiple features overlap. We developed Conditional Viral Expression by Ribozyme Guided Degradation (ConVERGD), a single-construct intersectional targeting strategy that combines a self-cleaving ribozyme with traditional FLEx switches. ConVERGD offers benefits over existing platforms, such as expanded intersectionality, the ability to accommodate larger and more complex payloads, and a vector design that is easily modified to better facilitate rapid toolkit expansion. To demonstrate its utility for interrogating neural circuitry, we employed ConVERGD to target an unexplored subpopulation of norepinephrine (NE)-producing neurons within the rodent locus coeruleus (LC) identified via single-cell transcriptomic profiling to co-express the stress-related endogenous opioid gene prodynorphin ( Pdyn ). These studies showcase ConVERGD as a versatile tool for targeting diverse cell types and reveal Pdyn -expressing NE + LC neurons as a small neuronal subpopulation capable of driving anxiogenic behavioral responses in rodents.
Golm, SK;Hübner, W;Müller, KM;
PMID: 37243260 | DOI: 10.3390/v15051174
Research on adeno-associated virus (AAV) and its recombinant vectors as well as on fluorescence microscopy imaging is rapidly progressing driven by clinical applications and new technologies, respectively. The topics converge, since high and super-resolution microscopes facilitate the study of spatial and temporal aspects of cellular virus biology. Labeling methods also evolve and diversify. We review these interdisciplinary developments and provide information on the technologies used and the biological knowledge gained. The emphasis lies on the visualization of AAV proteins by chemical fluorophores, protein fusions and antibodies as well as on methods for the detection of adeno-associated viral DNA. We add a short overview of fluorescent microscope techniques and their advantages and challenges in detecting AAV.
Leong, K;Lao, YH;Ji, R;Zhou, J;Snow, K;Kwon, N;Saville, E;He, S;Chauhan, S;Chi, CW;Datta, M;Zhang, H;Quek, CH;Cai, S;Li, M;Gaitan, Y;Bechtel, L;Wu, SY;Lutz, C;Tomer, R;Murray, S;Chavez, A;Konofagou, E;
PMID: 36712096 | DOI: 10.21203/rs.3.rs-2365576/v1
Gene editing in the mammalian brain has been challenging because of the restricted transport imposed by the blood-brain barrier (BBB). Current approaches rely on local injection to bypass the BBB. However, such administration is highly invasive and not amenable to treating certain delicate regions of the brain. We demonstrate a safe and effective gene editing technique by using focused ultrasound (FUS) to transiently open the BBB for the transport of intravenously delivered CRISPR/Cas9 machinery to the brain.
Martin, M;Vermeiren, S;Bostaille, N;Eubelen, M;Spitzer, D;Vermeersch, M;Profaci, CP;Pozuelo, E;Toussay, X;Raman-Nair, J;Tebabi, P;America, M;De Groote, A;Sanderson, LE;Cabochette, P;Germano, RFV;Torres, D;Boutry, S;de Kerchove d'Exaerde, A;Bellefroid, EJ;Phoenix, TN;Devraj, K;Lacoste, B;Daneman, R;Liebner, S;Vanhollebeke, B;
PMID: 35175798 | DOI: 10.1126/science.abm4459
The blood-brain barrier (BBB) protects the central nervous system (CNS) from harmful blood-borne factors. Although BBB dysfunction is a hallmark of several neurological disorders, therapies to restore BBB function are lacking. An attractive strategy is to repurpose developmental BBB regulators, such as Wnt7a, into BBB-protective agents. However, safe therapeutic use of Wnt ligands is complicated by their pleiotropic Frizzled signaling activities. Taking advantage of the Wnt7a/b-specific Gpr124/Reck co-receptor complex, we genetically engineered Wnt7a ligands into BBB-specific Wnt activators. In a "hit-and-run" adeno-associated virus-assisted CNS gene delivery setting, these new Gpr124/Reck-specific agonists protected BBB function, thereby mitigating glioblastoma expansion and ischemic stroke infarction. This work reveals that the signaling specificity of Wnt ligands is adjustable and defines a modality to treat CNS disorders by normalizing the BBB.
Liu, HM;Liao, ML;Liu, GX;Wang, LJ;Lian, D;Ren, J;Chi, XT;Lv, ZR;Liu, M;Wu, Y;Xu, T;Wei, JY;Feng, X;Jiang, B;Zhang, XQ;Xin, WJ;
PMID: 37352353 | DOI: 10.1126/sciadv.adg5849
The association between rewarding and drug-related memory is a leading factor for the formation of addiction, yet the neural circuits underlying the association remain unclear. Here, we showed that the interstitial nucleus of the posterior limb of the anterior commissure (IPAC) integrated rewarding and environmental memory information by two different receiving projections from ventral tegmental area (VTA) and nucleus accumbens shell region (NAcSh) to mediate the acquisition of morphine conditioned place preference (CPP). A projection from the VTA GABAergic neurons (VTAGABA) to the IPAC lateral region GABAergic neurons (IPACLGABA) mediated the effect of morphine rewarding, whereas the pathway from NAcSh dopamine receptor 1-expressing neurons (NAcShD1) to the IPAC medial region GABAergic neurons (IPACMGABA) was involved in the acquisition of environmental memory. These findings demonstrated that the distinct IPAC circuits VTAGABA→IPACLGABA and NAcShD1R→IPACMGABA were attributable to the rewarding and environmental memory during the acquisition of morphine CPP, respectively, and provided the circuit-based potential targets for preventing and treating opioid addiction.
Development (Cambridge, England)
DeBenedittis, P;Karpurapu, A;Henry, A;Thomas, MC;McCord, TJ;Brezitski, K;Prasad, A;Baker, CE;Kobayashi, Y;Shah, SH;Kontos, CD;Tata, PR;Lumbers, RT;Karra, R;
PMID: 36134690 | DOI: 10.1242/dev.200654
Heart regeneration requires multiple cell types to enable cardiomyocyte (CM) proliferation. How these cells interact to create growth niches is unclear. Here, we profile proliferation kinetics of cardiac endothelial cells (CECs) and CMs in the neonatal mouse heart and find that they are spatiotemporally coupled. We show that coupled myovascular expansion during cardiac growth or regeneration is dependent upon VEGF-VEGFR2 signaling, as genetic deletion of Vegfr2 from CECs or inhibition of VEGFA abrogates both CEC and CM proliferation. Repair of cryoinjury displays poor spatial coupling of CEC and CM proliferation. Boosting CEC density after cryoinjury with virus encoding Vegfa enhances regeneration. Using Mendelian randomization, we demonstrate that circulating VEGFA levels are positively linked with human myocardial mass, suggesting that Vegfa can stimulate human cardiac growth. Our work demonstrates the importance of coupled CEC and CM expansion and reveals a myovascular niche that may be therapeutically targeted for heart regeneration.
Glucokinase neurons of the paraventricular nucleus of the thalamus sense glucose and decrease food consumption
Kessler, S;Labouèbe, G;Croizier, S;Gaspari, S;Tarussio, D;Thorens, B;
| DOI: 10.1016/j.isci.2021.103122
The paraventricular nucleus of the thalamus (PVT) controls goal-oriented behavior through its connections to the nucleus accumbens (NAc). We previously characterized Glut2aPVT neurons that are activated by hypoglycemia, and which increase sucrose seeking behavior through their glutamatergic projections to the NAc. Here, we identified glucokinase (Gck)-expressing neurons of the PVT (GckaPVT) and generated a mouse line expressing the Cre recombinase from the glucokinase locus (GckCre/+ mice). Ex vivo calcium imaging and whole-cell patch clamp recordings revealed that GckaPVT neurons that project to the NAc were mostly activated by hyperglycemia. Their chemogenetic inhibition or optogenetic stimulation, respectively, enhanced food intake or decreased sucrose-seeking behavior. Collectively, our results describe a neuronal population of Gck-expressing neurons in the PVT, which has opposite glucose sensing properties and control over feeding behavior than the previously characterized Glut2aPVT neurons. This study allows a better understanding of the complex regulation of feeding behavior by the PVT.
