In vitro model of neurotrauma using the chick embryo to test regenerative bioimplantation

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Aina Mogas Barcons, Divya M. Chari, Christopher Adams
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Effective repair of spinal cord injury sites remains a major clinical challenge. One promising strategy is the implantation of multifunctional bioscaffolds to enhance nerve fiber growth, guide regener­ating tissue, and modulate scarring/inflammation processes. Given their multifunctional nature, such implants require testing in models which replicate the complex neuropathological responses of spinal injury sites. This is often achieved using live, adult animal models of spinal injury. However, these have substantial drawbacks for developmental testing, including the requirement for large numbers of animals, costly infrastructure, high levels of expertise, and complex ethical processes. As an alternative, we show that organotypic spinal cord slices can be derived from the E14 chick embryo and cultured with high viability for at least 24 days, with major neural cell types detected. A transecting injury could be reproducibly introduced into the slices and characteristic neuro­pathological responses similar to those in adult spinal cord injury observed at the lesion margin. This included aligned astrocyte morphologies and upregulation of glial fibrillary acidic protein in astrocytes, microglial infiltration into the injury cavity, and limited nerve fiber outgrowth. Bioimplan­tation of a clinical grade scaffold biomaterial was able to modulate these responses, disrupting the astrocyte barrier, enhancing nerve fiber growth, and supporting immune cell invasion. Chick embryos are inexpensive and simple, requiring facile methods to generate the neurotrauma model. Our data show the chick embryo spinal cord slice system could be a replacement spinal injury model for laboratories developing new tissue engineering solutions.

Plain language summary
Spinal cord injury can be highly debilitating for patients and carers. Repair of the spinal cord is therefore a major clinical goal but is challenging owing to the complex pathology of the injury site. Researchers need to mimic this complexity in the laboratory to test new therapies in realistic envi­ronments. Traditionally, researchers use live, adult animal models to achieve this, which are highly traumatic, variable, and costly. Here, we show an alternative system based on slices of spinal cord tissue from chick embryos that could partially replace live adult animal testing. We show slices can be grown in a dish and reproducibly injured, with complex pathology replicated. Further, we mod­ified cell responses in the injury through interface with a novel implant, potentially improving repair. The model is cost-effective, simple, and associated with less animal suffering than live adult animal experiments.

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How to Cite
Mogas Barcons, A., Chari, D. M. and Adams, C. (2024) “In vitro model of neurotrauma using the chick embryo to test regenerative bioimplantation”, ALTEX - Alternatives to animal experimentation, 41(2), pp. 202–212. doi: 10.14573/altex.2304171.

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