Question

Why do you suppose an animal virus grown in (and then isolated from) tissue culture might be more susceptible to inactivation by antibody than a similar virus propagated (and then isolated from) in an animal?

Assume you do the assay by isolating the viruses grown in these two different environments from antibody and then seek to compare in a controlled environment, which virus particle is inactivated more readily by the presence of appropriate antibody.

Answer 1

The first and prime most important reason that causes difference in susceptibility to inactivation of the virus grown in laboratory and the virus grown with in the animal body is that cells derived from plants and animals bodies are grown into tissue by using different reagents. The other factor is the matrix structure of tissue cultivated in lab is extremely different from original tissue. Virus grown on such tissue culture is exposed to contaminating agents other than mycoplasma due to which their ability of replicate becomes halted as compared to their replication with in an original tissue in an organism or in-vitro cultivation. Factors such as pH, presence of dyes in the growth medium etc. also make lab grown viruses more susceptible to inactivation

Use of non-immortalized primary cells taken directly from a living organism for isolation of viruses often harbor latent viruses or viruses that produce a persistent but subclinical infection of the host.

In vivo cultivation, cells have to deal with functional immune system which is not the case with the cell grown outside the host and away from the immune system. This makes the cell be fully permissive and the virus thus will cause highly cytopathic effects