Application of CRISPR/Cas9 System in Establishing Large Animal Models

Abstract

The foundation for investigating the mechanisms of human diseases is the establishment of animal models, which are also widely used in agricultural industry, pharmaceutical applications, and clinical research. However, small animals such as rodents, which have been extensively used to create disease models, do not often fully mimic the key pathological changes and/or important symptoms of human disease. As a result, there is an emerging need to establish suitable large animal models that can recapitulate important phenotypes of human diseases for investigating pathogenesis and developing effective therapeutics. However, traditional genetic modification technologies used in establishing small animal models are difficultly applied for generating large animal models of human diseases. This difficulty has been overcome to a great extent by the recent development of gene editing technology, especially the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9). In this review, we focus on the applications of CRISPR/Cas9 system to establishment of large animal models, including nonhuman primates, pigs, sheep, goats and dogs, for investigating disease pathogenesis and treatment. We also discuss the limitations of large animal models and possible solutions according to our current knowledge. Finally, we sum up the applications of the novel genome editing tool Base Editors (BEs) and its great potential for gene editing in large animals.

CRISPR-Cas System: The Current and Emerging Translational Landscape

“…Genetically modified large animal models are of significant importance because they are used in the development of new therapies and as research models of human diseases. They are used to demonstrate the feasibility of in vivo CRISPR editing of somatic and germline cells as a therapeutic approach, and to evaluate pre-clinical efficacy and safety of new drugs prior to the initiation of clinical trials [ 242 ].…”

“…The main large animal models currently used to mimic human diseases are non-human primates, pigs, sheep, goats, and dogs [ 242 ] ( Figure 6 ). Non-human primates are the preferred model, not only due to their similarity in physiology and genetics, but also because they display cognition and social behaviors as well.…”

Neuronal oscillations: early biomarkers of psychiatric disease?

“…They not only exhibit complex cognitive, social, and behavioral processes, but they also offer general similarity of brain structures compared to humans, such as the expanded prefrontal cortex (PFC), which is essential for higher-order processes (Chini and Hanganu-Opatz, 2021 ). With the discovery of new-generation gene editing tools, non-human primate models of NDDs have received increased interest in recent years (Lin et al, 2022 ). Insights into the pathophysiology of ASD have been obtained based on macaque NDD models, including a reduced expression of excitatory synaptic proteins, such as glutamate receptors and PSD95, in SHANK3-deficient macaques and an increased presence of GFAP-positive astrocytes in a brain region-specific manner (Liu et al, 2016 ; Zhao et al, 2017 ; Zhou et al, 2019 ).…”

Multiplex CRISPR-Cas Genome Editing: Next-Generation Microbial Strain Engineering

“…Unlike zinc-finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs) that require protein engineering for recognition of wanted target DNA sequences, crRNA can be easily designed and modified . This flexibility has enabled the wide use of CRISPR-Cas technology in genome editing of almost all organisms, from bacteria to yeast, fungi, plants, insects, animals, and humans. − To expedite genome editing, the multiplex editing method is being employed, enabling simultaneous editing at two or more loci in the genome (Figure ). This approach reduces repeated plasmid integration, recombination processes, cost, and labor.…”