Zika Virus: A Neurotropic Warrior against High-Grade Gliomas-Unveiling Its Potential for Oncolytic Virotherapy.

Gliomas account for approximately 75-80% of all malignant primary tumors in the central nervous system (CNS), with glioblastoma multiforme (GBM) considered the deadliest. Despite aggressive treatment involving a combination of chemotherapy, radiotherapy, and surgical intervention, patients with GBM have limited survival rates of 2 to 5 years, accompanied by a significant decline in their quality of life. In recent years, novel management strategies have emerged, such as immunotherapy, which includes the development of vaccines or T cells with chimeric antigen receptors, and oncolytic virotherapy (OVT), wherein wild type (WT) or genetically modified viruses are utilized to selectively lyse tumor cells. In vitro and in vivo studies have shown that the Zika virus (ZIKV) can infect glioma cells and induce a robust oncolytic activity. Consequently, interest in exploring this virus as a potential oncolytic virus (OV) for high-grade gliomas has surged. Given that ZIKV actively circulates in Colombia, evaluating its neurotropic and oncolytic capabilities holds considerable national and international importance, as it may emerge as an alternative for treating highly complex gliomas. Therefore, this literature review outlines the generalities of GBM, the factors determining ZIKV's specific tropism for nervous tissue, and its oncolytic capacity. Additionally, we briefly present the progress in preclinical studies supporting the use of ZIKV as an OVT for gliomas.

Multifunctional magnetoliposomes as drug delivery vehicles for the potential treatment of Parkinson's disease.

Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease. Therefore, development of novel technologies and strategies to treat PD is a global health priority. Current treatments include administration of Levodopa, monoamine oxidase inhibitors, catechol-O-methyltransferase inhibitors, and anticholinergic drugs. However, the effective release of these molecules, due to the limited bioavailability, is a major challenge for the treatment of PD. As a strategy to solve this challenge, in this study we developed a novel multifunctional magnetic and redox-stimuli responsive drug delivery system, based on the magnetite nanoparticles functionalized with the high-performance translocating protein OmpA and encapsulated into soy lecithin liposomes. The obtained multifunctional magnetoliposomes (MLPs) were tested in neuroblastoma, glioblastoma, primary human and rat astrocytes, blood brain barrier rat endothelial cells, primary mouse microvascular endothelial cells, and in a PD-induced cellular model. MLPs demonstrated excellent performance in biocompatibility assays, including hemocompatibility (hemolysis percentages below 1%), platelet aggregation, cytocompatibility (cell viability above 80% in all tested cell lines), mitochondrial membrane potential (non-observed alterations) and intracellular ROS production (negligible impact compared to controls). Additionally, the nanovehicles showed acceptable cell internalization (covered area close to 100% at 30 min and 4 h) and endosomal escape abilities (significant decrease in lysosomal colocalization after 4 h of exposure). Moreover, molecular dynamics simulations were employed to better understand the underlying translocating mechanism of the OmpA protein, showing key findings regarding specific interactions with phospholipids. Overall, the versatility and the notable in vitro performance of this novel nanovehicle make it a suitable and promising drug delivery technology for the potential treatment of PD.

Extracellular vesicles of U937 macrophage cell line infected with DENV-2 induce activation in endothelial cells EA.hy926.

Endothelial activation and alteration during dengue virus (DENV) infection are multifactorial events; however, the role of extracellular vesicles (EVs) in these phenomena is not known. In the present study, we characterized the EVs released by DENV-2 infected U937 macrophage cell line and evaluated the changes in the physiology and integrity of the EA.hy926 endothelial cells exposed to them. U937 macrophages were infected, supernatants were collected, and EVs were purified and characterized. Then, polarized endothelial EA.hy926 cells were exposed to the EVs for 24 h, and the transendothelial electrical resistance (TEER), monolayer permeability, and the expression of tight junction and adhesion proteins and cytokines were evaluated. The isolated EVs from infected macrophages corresponded to exosomes and apoptotic bodies, which contained the viral NS3 protein and different miRs, among other products. Exposure of EA.hy926 cells to EVs induced an increase in TEER, as well as changes in the expression of VE-cadherin and ICAM in addition leads to an increase in TNF-α, IP-10, IL-10, RANTES, and MCP-1 secretion. These results suggest that the EVs of infected macrophages transport proteins and miR that induce early changes in the physiology of the endothelium, leading to its activation and eliciting a defense program against damage during first stages of the disease, even in the absence of the virus.

Assembly and release of Dengue virus: Role of Alix protein / Ensamblaje y liberación del virus dengue: controversia sobre la participación de la proteína alix

RESUMEN Algunos virus envueltos usurpan la maquinaria celular ESCRT (complejo de clasificación endosomal requerido para el transporte) para llevar a cabo funciones como la transcripción, la traducción, el ensamblaje y la liberación de partículas virales desde las células huésped. Aunque esta estrategia ha sido estudiada principalmente en retrovirus, son varios los virus envueltos que la usan. El objetivo del trabajo fue explorar la participación de una proteína accesoria de ESCRT, la proteína Alix, en la transcripción, traducción, ensamblaje y liberación del virus dengue (DENV), así como su interacción con la proteína viral NS3. Células A549 infectadas con DENV2 fueron tratadas con pequeños ARN de interferencia (siRNA) para disminuir la expresión ("knock-down") de la proteína Alix. Simultáneamente, se obtuvo una línea A549 que expresaba una proteína NS3 recombinante y sobre este sistema se hicieron ensayos de inmunoprecipitación y "pull-down" para detectar interacción entre NS3 y Alix. Los resultados mostraron que el "knock-down" de Alix no tuvo efecto notable en la transcripción o la traducción viral, pero sí en el ensamblaje y la liberación de DENV2, mientras que los ensayos de "pull-down" revelaron la interacción entre NS3 y Alix. La participación de Alix en la producción de DENV2 y su interacción con NS3 constituyen un potencial blanco para el diseño de estrategias dirigidas a controlar la propagación de DENV.

ABSTRACT Since the finding that HIV recruits cellular ESCRT (endosomal sorting complexes required for transport) machinery to accomplish viral budding, this strategy has emerged as an escape route for enveloped viruses also. The work aimed to explore the participation of the cellular protein Alix (a human protein that acts as an adapter in the ESCRT pathway) on the transcription, protein expression, assembly and release of Dengue virus (DENV), and explore for its potential interaction with the viral protein NS3. To this purpose, A549 cells were infected with DENV2 and treated with small interfering RNAs (siRNA) to generate an Alix stable knockdown cells line. Also, an A549 cells line expressing a histidine-tagged NS3 protein was obtained. Both cells lines were used in immunoprecipitation and pull-down assays to assess the interaction between NS3 and Alix. The results showed that Alix knockdown had no effect on viral transcription or viral protein expression but influenced the assembly and release of DENV2 negatively. Finally, pull-down assays revealed the interaction between NS3 and Alix. The finding of an Alix participation in the production of DENV2 and its interaction with NS3 provides a potential target for the design of control/inhibition strategies against DENV spread.

In Vitro Infection with Dengue Virus Induces Changes in the Structure and Function of the Mouse Brain Endothelium.

BACKGROUND: The neurological manifestations of dengue disease are occurring with greater frequency, and currently, no information is available regarding the reasons for this phenomenon. Some viruses infect and/or alter the function of endothelial organs, which results in changes in cellular function, including permeability of the blood-brain barrier (BBB), which allows the entry of infected cells or free viral particles into the nervous system. METHODS: In the present study, we standardized two in vitro models, a polarized monolayer of mouse brain endothelial cells (MBECs) and an organized co-culture containing MBECs and astrocytes. Using these cell models, we assessed whether DENV-4 or the neuro-adapted dengue virus (D4MB-6) variant infects cells or induces changes in the structure or function of the endothelial barrier. RESULTS: The results showed that MBECs, but not astrocytes, were susceptible to infection with both viruses, although the percentage of infected cells was higher when the neuro-adapted virus variant was used. In both culture systems, DENV infection changed the localization of the tight junction proteins Zonula occludens (ZO-1) and Claudin-1 (Cln1), and this process was associated with a decrease in transendothelial resistance, an increase in macromolecule permeability and an increase in the paracellular passing of free virus particles. MBEC infection led to transcriptional up-regulation of adhesion molecules (VCAM-1 and PECAM) and immune mediators (MCP-1 and TNF- α) that are associated with immune cell transmigration, mainly in D4MB-6-infected cells. CONCLUSION: These results indicate that DENV infection in MBECs altered the structure and function of the BBB and activated the endothelium, affecting its transcellular and paracellular permeability and favoring the passage of viruses and the transmigration of immune cells. This phenomenon can be harnessed for neurotropic and neurovirulent strains to infect and induce alterations in the CNS.