Marg,

Nice protocol. Tammy probably has this covered with her multi-tissue
block, which is the best way to go for tumor diagnostics.

In most cases, there are usually tissues that are negative, so I feel
using a dedicated negative control tissue is usually a waste of time and
effort.


Tim Morken, B.S., EMT(MSA), HTL(ASCP)
Infectious Disease Pathology
Centers for Disease Control
MS-G32
1600 Clifton Rd.
Atlanta, GA 30333
USA

email: tim9@cdc.gov
       timcdc@hotmail.com

FAX:  (404)639-3043


----Original Message Follows----
Date: Mon, 12 Oct 1998 08:34:00 -0700
From: "Hagerty, Marjorie A." <mhagerty@emc.org>
Subject: RE: Negative controls for immunos
To: Histonet <histonet@pathology.swmed.edu>


Hi Tammy,
This is our policy concerning immuno controls. This policy is not for
immunos that we quantitate.
IMMUNOHISTOCHEMISTRY CONTROLS: Immunostains performed in the histology
laboratory are controlled by the utilization of positive and negative
control slides that are stained simultaneously with the test case to
validate that the staining procedure effectively demonstrates the
material
for which the stain is designated. The negative controls are used in
conjunction with the positive controls in an effort to identify
non-specific
staining reactions. Slides from both the patient and the control are
treated
with non-immune control serum in place of the antibody. In addition,
every
 positive control contains cells and/or specific areas which are
negative
for the antibody employed and which serve as internal negative controls
as
well.

Marg
EMC
 ----------
From: Barnhart, Tammy
To: histonet@pathology.swmed.edu
Subject: Negative controls for immunos
Date: Monday, October 12, 1998 7:19AM

Histonetters,
                Question, a new CAP standard (08.2257) states, " Are
negative controls used for each antibody?".  We were wondering how this
standard is applied at other labs.  At this time we only run negative
controls on different tissue blocks used, both patient specimens and
controls.  We use several multitissue control blocks ( one for CDs, one
for
keratins, etc) and will run different negative controls for different
serum
types (ie: rabbit or mouse).  If we interprete this standard literally,
we
will greatly increase the number of slides handled and, almost, double
our
reagent costs.  Which brings up a second question, how do you handle
your
negative controls?  Do you run them completely, using serum instead of
primary antibody, or do an abbreviated procedure?  All reponses would be
appreciated.  Thanks in advance,

Tammy Barnhart









______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com