Neurotrophic factor expression after CNS viral injury produces enhanced sensitivity to psychostimulants : potential mechanism for addiction vulnerability

Hypothesized risk factors for psychostimulant, amphetamine, and cocaine abuse include dopamine (DA) receptor polymorphisms, HIV infection, schizophrenia, drug-induced paranoias, and movement disorders; however, the molecular, cellular, and biochemical mechanisms that predispose to drug sensitivity or drive the development of addiction are incompletely understood. Using the Borna disease rat, an animal model of viralinduced encephalopathy wherein sensitivity to the locomotor and stereotypic behavioral effects of D-amphetamine and cocaine is enhanced (Solbrig et al., 1994, 1998), we identify a specific neurotrophin expression pattern triggered by striatal viral injury that increases tyrosine hydroxylase activity, an early step in DA synthesis, to produce a phenotype of enhanced amphetamine sensitivity. The reactive neurotrophin pattern provides a molecular framework for understanding how CNS viral injury, as well as other CNS adaptations producing similar growth factor activation profiles, may influence psychostimulant sensitivity

Adjuvant effects of a sequence-engineered mRNA vaccine: translational profiling demonstrates similar human and murine innate response

Additional file 1: Fig. S1. Components and assembly of the PTE module for innate responses. (A) Top panel—in vivo monocytes continuously emigrate from the blood into peripheral tissues with a half-life in the blood of ~1 day. Bottom panel: In vitro generation of cytokine derived DCs from monocytes involves the addition of IL-4 and GM-CSF and culture for 7–11 days. (B) Schematic of the components of a MIMIC-PTE module. In the 3D PTE, differentiation occurs in hours to about 2 days triggered by migration into and out of (reverse migration) through the endothelium: a process reminiscent of the movement of cells from tissues into lymphatic vessels

Orbivirus non-structural protein NS2

Bluetongue virus (BTV) is an economically important arthropod-borne virus that causes Bluetongue disease in sheep and other ruminants. BTV is the prototypical orbivirus and is a member of the Reoviridae family. Other arthropod-borne orbiviruses include African horse-sickness virus (AHSV) and epizootic haemorraghic disease virus (EHDV). The virus contains 10 dsRNA segments that encode for both structural and non-structural proteins. The structural proteins of orbiviruses and other members of the Reoviridae, such as reoviruses and rotaviruses, are arranged in a very similar layered arrangement. The roles of the non-structural proteins are largely unknown. This thesis describes the functional characterisation of one of these nonstructural proteins, NS2.The NS2 protein of BTV-10 was purified to a high degree of homogeneity from insect cells. This purified protein was used in crystal screening experiments and in circular dichroism (CD) experiments. Although a wide range of conditions were tried for crystallography, no crystals were obtained. This may be due to sequence or conformational heterogeneity. Size-exclusion chromatography was used to show that purified NS2 exists in large multimers, supporting the conclusion that conformational heterogeneity was responsible for the lack of crystal formation. CD revealed that NS2 has a high α-helical content.NS2 is a ssRNA-binding protein. To identify the nucleotides within the viral RNA segments that are important for recognition by NS2, gel-shift and uvcrosslinking experiments with various labelled synthetic RNA probes and in vitro transcripts were performed. Initial gel shift analysis with short synthetic RNAs indicated that NS2 bound a sequence corresponding to the conserved 5' terminus of rotavirus genomic RNA. Similar sequences, called the NS2 target sequence or NTS, were identified in all 10 BTV segments. A number of truncations and deletions of BTV segments M4 and S10 were created to investigate the role of this aptamer in NS2 binding. The results indicate that the NTS is required for the binding of NS2 to each BTV viral RNA segment. These results were confirmed by using short synthetic RNA probes corresponding to the aptamer identified in segments M4 and S10 and by showing that the aptamer could confer NS2 binding to non-BTV RNA.Further biochemical analysis of NS2 revealed previously undescribed features of the protein. Chemical crosslinking and co-immunoprecipitation studies showed that NS2 can interact with VP1 the viral RNA polymerase. The inclusion of NS2 in in vitro transcription-translation and translation reactions demonstrated a specific shutdown of BTV protein synthesis, suggesting a role for the protein in a switch from viral RNA translation to RNA packaging. This translation inhibition is dependant on the concentration of NS2 present and may be related to the formation of viral inclusion bodies. NS2 was also found to bind nucleotide triphosphates and to have phosphohydrolase activity. Kinase inhibitors were used to identify casein kinase n as the cellular kinase that phosphorylates NS2 in vivo.</p

Neuroprotection and Reduced Proliferation of Microglia in Ribavirin-Treated Bornavirus-Infected Rats

In a rat model of Borna disease, intracerebral ribavirin caused clinical improvement without changes in virus titer or nucleic acid. Levels of microglia and infiltrating CD4 and CD8 cells were decreased, despite increases in mRNAs encoding interleukin-1β (IL-1β), IL-10, and gamma interferon in the brain. Intracerebral ribavirin may reduce morbidity through effects on microglia cell proliferation

Co-administration of an effector antibody enhances the half-life and therapeutic potential of RNA-encoded nanobodies

Abstract The incidence of Clostridioides difficile infection (CDI) and associated mortality have increased rapidly worldwide in recent years. Therefore, it is critical to develop new therapies for CDI. Here we report on the development of mRNA-LNPs encoding camelid-derived VHH-based neutralizing agents (VNAs) targeting toxins A and/or B of C. difficile. In preclinical models, intravenous administration of the mRNA-LNPs provided serum VNA levels sufficient to confer protection of mice against severe disease progression following toxin challenge. Furthermore, we employed an mRNA-LNP encoded effector antibody, a molecular tool designed to specifically bind an epitopic tag linked to the VNAs, to prolong VNA serum half-life. Co-administration of VNA-encoding mRNA-LNPs and an effector antibody, either provided as recombinant protein or encoded by mRNA-LNP, increased serum VNA half-life in mice and in gnotobiotic piglets. Prolonged serum half-life was associated with higher concentrations of serum VNA and enhanced prophylactic protection of mice in challenge models