In article <xE-ZmTw.ksturts at delphi.com>, Keith Sturts <ksturts at delphi.com>
> I'm not a virologist but am interested in the reason why some families of
> mammals are not susceptible to some viruses, such as the common cold virus
> in humans. It is hard to find this information and I thought some one here
> would know.
>> What is the physiological, metabolic, or other mechanism operating that
> prohibits the common cold virus from effecting dogs, for instance.
>> In those viruses that do or do not attack families of mammals, are the
> cellular considerations, differentials, etc., always the same? (I realize
> that I am hardly using the proper terminology as a layman, but I hope
> most know what I mean.
>> Thanks for your patience and any help you can give me on this subject.
>> Keith Sturts
Keith, I hope this answers your question ----
The infection of a cell by a virus requires the binding of a protein on
the virus's surface to a receptor on the host cell. Without this
interaction, the virus is unable to enter the host cell and replicate.
The viral receptor-binding protein varies among strains of virus, and it
is instrumental in determining the host range of a virus -- ie, if an
animal doesn't express the receptor to which the virus must bind, then the
animal cannot be infected.