Animal Models of Inherited Retinal Degenerations

Introduction to Inherited Retinal Degenerations

Inherited retinal degenerations (IRDs) have been regarded as a type of visual impairment disease that can lead to blindness. Studies have shown that mutations in genes related to retinal function are the main cause of IRD disease. For example, a group of genes, including RPE65 and LRAT, have been identified that are associated with the IRD progress. Moreover, pilot studies have indicated that loss of photoreceptor cells can be usually found in IRD patients, and thus inhibiting the delivery process of the absorbed photons into neuronal cells. Therefore, a battery of neuroproteins can prevent the dysfunction of photoreceptor cells or promote the production of specific neuroprotective molecules. In addition, various IRD-based animal models have been established for facilitating the elucidation of pathogenic mechanisms and the development of therapeutic options. Up to date, a variety of therapies, such as gene therapy, have been generated for treating IRD in preclinical or clinical trials.

Fig.1 Schematic of retinal layers and associated genes in inherited retinal degenerations. (Winkler, 2020)

IRDs Animal Models

Currently, animal models have been broadly used as suitable materials for revealing the mechanism of neurodegenerative diseases, especially for IRDs. Note, many reports have indicated that genetic mutations in these animal models can lead to IRDs occurrence. Moreover, many of the mutations found in animals have been gradually confirmed in IRDs patients. As a result, animal models can truly convey the genetic characteristics of IRDs, provide potential candidate genes, and study the pathological properties of the mutated genes, as well as provide meaningful data for drug safety and efficacy research. Nowadays, animal models have been classified into two main groups, genetically engineered animal models and natural animal models. Among them, the fruitfly has become an important natural model for elucidating normal visual processes and screening IRDs-causing mutations. Also, knock-out animals have been considered as key genetically engineered models for evaluating the safety and effectiveness of candidate IRDs drugs in preclinical trials.

Large IRD Animal Models

Large animals and humans have high similarities in size and pathogenic mutations, which can simulate the development of genetic diseases. Until now, a variety of large IRDs animal models, such as dogs, cats, and non-human primates, have been established for the study of IRD pathogenesis and the development of new therapies. For instance, different kinds of large animal models with specific genetic mutations have been designed to help the understanding of various mechanisms of IRD development. Among them, pig and dog models of RHO, PDE6A, PDE6B, or PDE6C variations have become the most common models type for revealing the process of photoreceptor death, the formation of rod PDE heteromeric holoenzyme. Besides, recent progress in gene-editing technology offers great potential for the development of more accurate large animal models with new mutations.

Creative Biolabs concentrates on promoting the development of animal models for neurological disorders. We will combine many advanced tools with other incredible technologies around the world to boost the generation of novel IRD-based animal models in unprecedented ways. In our company, our scientists specialized in neurological disorders studies will work with you to develop the most appropriate strategy that will offer reproducible data for your research. If you are interested in our services, please feel free to contact us for closer communication to learn how we can be involved in your project. Separate services or integrated end-to-end solutions are all welcomed.

Reference

1. Winkler, P. A.; et al. Large animal models of inherited retinal degenerations: a review. Cells. 2020, 9(4): 882.