Morphological and biochemical characterisation of sensory neurons infected in vitro with rabies virus

Abstract

This work was aimed at the morphological and biochemical characterisation of the most susceptible neuronal subpopulation to rabies virus (RABV) infection. Adult mouse DRG cultures were infected with RABV and double-processed for viral antigen detection and neuropeptides: calcitonin gene-related peptide (CGRP), galanin (GAL), substance P (SP), neuropeptide Y (NPY) and vasoactive intestinal peptide (VIP). It was found that 56% of the neurons in culture were small (diameter < 20 microm) but, in spite of this, 69% of the infected neurons had intermediate and large diameters (> or = 20 microm). More than 50% of infected neurons expressed NPY, VIP or SP, whereas no association was found between infected neurons and the presence of CGRP or GAL. Despite SP having been shown to be a small neuron marker, it was found that RABV infects medium and large-sized SP positive cells. RABV preference for larger neurons could explain part of the neuropathogenesis since it can be suggested that, following a rabid accident, the virus uses large neurons (mainly innervating muscle and joints) in vivo to be transported later on to the central nervous system.

Role of Oxidative Stress in Rabies Virus Infection of Adult Mouse Dorsal Root Ganglion Neurons

“…Similar to previous reports of DRG neurons in cultures (14,29), we have found that CVS infects only a subpopulation (33 to 54%) of DRG neurons. CVS infection did not cause a loss of neuronal viability over 72 h in CVS-infected DRG neurons above baseline levels observed with the mock-infected cultures.…”

“…We have studied CVS infection in cultured DRG sensory neurons because they are known to be relatively permissive to in vitro infection with rabies virus (2,14,(27)(28)(29), with survival of rabies virus-infected DRG neurons for more than 20 days without cytopathic effects observed with the cultures (27). Hence, DRG neurons are an amenable neuronal cell type for an assessment of changes in morphology and/or growth of their neurites (axons) in rabies virus infection.…”

“…In order to evaluate this hypothesis, we have studied CVS versus mock infection of cultured adult mouse DRG neurons in order to determine the role of oxidative stress on rabies virus-infected DRG neurons and their neurites (axons). We have used cultured DRG neurons because these neurons are known to be relatively permissive to rabies virus infection (2,14,(27)(28)(29), which facilitates evaluation of processes involving axons. …”

Role of Oxidative Stress in Rabies Virus Infection

“…We have used cultured DRG neurons because these neurons are known to be relatively permissive to rabies virus infection (Castellanos et al, 2000;Martinez-Gutierrez and Castellanos, 2007;Tsiang et al, 1989Tsiang et al, , 1991Tuffereau et al, 2007), which facilitates evaluation of mechanisms of disease involving axons. DRG neurons from adult rodents are most suitable for the evaluation of neurites (axons).…”

The Rabies Virus Phosphoprotein Synthesis and Subcellular Localization are Modified by Nerve Growth Factor

“…Our group has previously reported a neurotrophin antitranscriptional and antireplicative effect in dorsal root ganglion (DRG) neuron cultures infected with RABV (Castellanos et al, 2000;Castellanos et al, 2005;Martínez-Gutiérrez & Castellanos, 2007). These findings, plus results obtained more recently using cellular kinase inhibitors, have suggested cell machinery regulation of the function of proteins directly participating in viral transcription and replication events, among them being the P protein (unpublished results).…”