Gene Editing for Treatment of Neurological Infections

Abstract

The study of neurological infections by viruses defines the field of neurovirology, which has emerged in the last 30 years and was founded upon the discovery of a number of viruses capable of infecting the human nervous system. Studies have focused on the molecular and biological basis of viral neurological diseases with the aim of revealing new therapeutic options. The first studies of neurovirological infections can be traced back to the discovery that some viruses have an affinity for the nervous system with research into rabies by Louis Pasteur and others in the 1880s. Today, the immense public health impact of neurovirological infections is illustrated by diseases such as neuroAIDS, progressive multifocal leukoencephalopathy, and viral encephalitis. Recent research has seen the development of powerful new techniques for gene editing that promise revolutionary opportunities for the development of novel therapeutic options. In particular, clustered regulatory interspaced short palindromic repeat-associated 9 system provides an effective, highly specific and versatile tool for targeting DNA viruses that are beginning to allow the development of such new approaches. In this short review, we discuss these recent developments, how they pertain to neurological infections, and future prospects.

Novel AIDS therapies based on gene editing

“…Choi et al delivered the Cas9 protein itself together with gRNA pre-packaged in lentiviral particles for transient exposure and showed effective gene disruption in cells [89]. Thus there are a number of possible solutions to delivery including delivering Cas9 and gRNAs separately or splitting the Cas9 enzyme into separately delivered subdomains as we have reviewed recently [90]. …”

CRISPR Editing Technology in Biological and Biomedical Investigation

“…In October of 2016, the first clinical trial of CRISPR technology was begun when PD-1 knockout engineered T cells were injected into human subjects as a therapy for metastatic non-small cell lung cancer [Cyranoski, 2016]. We have been interested in our research in developing CRISPR/Cas9 approaches to human pathogenic viruses [White et al, 2015[White et al, , 2016Khalili et al, 2017], in particular HIV-1, which causes AIDS, and Polyomavirus JC (JCV), which causes progressive multifocal leukoencephalopathy [PML; Wollebo et al, 2015b]. We will discuss these studies in the following section as well as CRISPR strategies to other human virus.…”

“…Now that CRISPR effector endonucleases are available to target RNA, for example, FnCas9 directed by an engineered RNA-targeting gRNA, inhibition of human RNA viruses such as hepatitis C virus within eukaryotic cells should be possible [Price et al, 2015]. Our research has focused on several pathogenic human viruses, including JCV, which is a circular double-stranded DNA virus [Wollebo et al, 2015b], HIV-1, which is a retrovirus [Hu et al, 2014;Khalili et al, 2015Khalili et al, , 2017White et al, 2015White et al, , 2016Zhang et al, 2015a;Kaminski et al, 2016a,b,c;White and Khalili, 2016a;Yin et al, 2016Yin et al, , 2017 and HSV-1 a herpesvirus comprised of a double-stranded DNA of greater than 100 Kbp in size [McGeoch et al, 2006]. JCV causes PML, a lethal CNS demyelinating disease, which ensues when the virus actively replicates in the oligodendrocytes and astrocytes of the central nervous system (CNS) producing cytolysis, demyelinated lesions, and devastating neurological consequences [Wollebo et al, 2015b].…”

“…[Wang et al, 2016a, e;Khalili et al, 2017]. Thus, when designing any gene editing strategy against HIV, it is essential to consider the possibility of escape mutants arising [White et al, 2016]. In principle, multiplex gRNAs can be employed so that the chance of generating escape mutants can be greatly reduced, since the probability of viable mutations occurring at multiple sites is much less than for a single site.…”

“…Different approaches have been employed to eradicate HIV from these reservoirs including the so-called "shock and kill" approach, where latent virus is triggered by cellular reactivation so as to purge virus-producing cells. However, an approach using CRISPR geneediting for inactivating integrated proviral DNA in the genome of latently infected cells has the potential to eliminate latent viral reservoirs allowing a sterile cure of AIDS [Khalili et al, 2015[Khalili et al, , 2017White et al, 2016]. CRISPR/Cas9 can be used either to disrupt the integrated HIV-1 provirus or the cellular genes that are required for productive HIV-1 infection.…”