Viral neuronal tracing

File:Targeting-of-Pseudorabies-Virus-Structural-Proteins-to-Axons-Requires-Association-of-the-Viral-Us9-ppat.1000065.s001.ogv


Viral neuronal tracing is the use of a virus to trace neural pathways, providing a self-replicating tracer. Viruses have the advantage of self replication over molecular tracers, but can also spread too quickly and cause degradation of neural tissue. Viruses which can infect the nervous system, called neurotropic viruses, spread through spatially close assemblies of neurons through synapses, allowing for their use in studying functionally connected neural networks. The use of viruses to label functionally connected neurons stems from work done by Albert Sabin who developed a bioassay which could assess the infection of viruses across neurons. Subsequent research allowed for incorporation of immunohistochemical techniques to systematically label neuronal connections. To date, viruses have been used to study multiple circuits in the nervous system.

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Direction of transmission

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Methods

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Benefits and drawbacks

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