Hi,
    I see no use running a negative control for each block if the processes are
identical. Exception being the Herceptest, solely because it is FDA approved,
and that is what they expect of this method. It is appropriate to have one
representative control but it needn't be one for each block. That would be very
redundant, impractical, and unnecessary. We've never had a deficiency for this
and I would like to hear of anyone who has.
Amos Brooks

"Mackinnon, John" wrote:

> When running negative reagent controls you should be running a negative for
> each block, if you are running both monoclonal and polyclonal antibodies you
> should run a negative for each of these.  If one of your antibodies requires
> HIER another enzyme and one no pretreatment you should be running a negative
> for each of these.  All of your controls must be treated the same way that
> your test sections are treated, if you don't do this you are not really
> controlling the procedure.  Expense is no excuse for not running proper QC.
> I can't remember ever hearing a biochemist saying that they were not going
> to run all of the appropriate QC because it seemed excessive and expensive.
>
> John MacKinnon MLT, ART
> Senior Technologist, Pathology
> Lakeridge Health Oshawa
> Ontario, Canada