Hello John,

I was just lurking for the weekend to see if anyone would have any other ideas
regarding a true negative control for polyclonal antibodies.

In my mind the best true control for a polyclonal antibody is the very same
serum
with the addition of the specific antigen it is directed against.  We have
used this
method in liquid phase tests using insulin and anti-insulin antisera.  I
know that
there are bound to be problems with this method on tissue sections due to
conformational changes in antigen structure in a solid phase compared to its
immunizing form, but absorbtion controls seem to me to be the best
alternative for
a negative control.

Anybody who agrees, disagrees or just wants to argue because its Monday
morning is invited to comment.


regards


BJC - Brian
On Thu, 15 Oct 1998 08:10:34 -0700 Tarpley, John wrote:

> From: Tarpley, John <jtarpley@amgen.com>
> Date: Thu, 15 Oct 1998 08:10:34 -0700
> Subject: RE: Neg Immunocontrols
> To: "A. Mark Briones" <3briones@thesocket.com>,
>      'brian chelack' <chelack@admin3.usask.ca>
> Cc: HistoNet Server <HistoNet@Pathology.swmed.edu>
>
> The point on polyclonal antisera is well taken and that's why, whenever
> possible, we use preimmune serum from the same animal or pool of animals
> used to produce the antibody diluted to the same Ig concentration as the
> primary antibody. By using this control you can see if any "background"
> antibodies already present in the serum will affect your results.
> Unfortunately, this is rarely possible when using commercial antibodies. Can
> anyone suggest a true negative control for polyclonals in this case?
>
> John Tarpley 15-2-B
> Specialist Image Analysis & Immunohistochemistry
> Amgen Inc
> One Amgen Center Drive
> Thousand Oaks, CA  91320
>
>
> > ----------
> > From: 	brian chelack[SMTP:chelack@admin3.usask.ca]
> > Sent: 	Wednesday, October 14, 1998 5:07 PM
> > To: 	A. Mark Briones
> > Cc: 	HistoNet Server
> > Subject: 	Re: Neg Immunocontrols
> >
> >
> >
> > Just a quick observation regarding the use of "non-immune sera" as a
> > negative
> > control.  Investigators should be aware that non immune sera will always
> > contain
> > antibodies to other common pathogens that the negative control animal has
> > experienced in its past.  A case in point in our lab was the use of
> > "non-immune
> > rabbit sera as a control alongside a rabbit antisera for Bovine
> > respiratory syncitial
> > virus.