Hi Melanie,
Background staining with kappa and lambda is common and really to be
expected to some extent, because there are antibody molecules with
associated heavy and light chains attached circulating in the serum. For
paraffin sections, the best one can do is to set the titre to minimize the
background while keeping the staining of plasma cells easily visible. It
becomes even more of a problem on frozen sections because more of the light
chains are available to stain and so background can make evaluation of
surface K and L difficult. We therefore use two dilutions on every frozen
case to insure that we get the one with the best balance of titre and
background to read.  Hope this helps a little.

Best Regards,

Mickie [Retired after this Friday 7/28 and looking for locum tenens work :)
]

Michael L Johnson, BS, HTL(ASCP)
Histology Supervisor
Department of Pathology
Sacred Heart Medical Center
W. 101 8th Avenue
Spokane, WA 99220

johnsom@shmc.org


-----Original Message-----
From: Trivett Melanie (PMC)
[mailto:TrivettMelanie@petermac.unimelb.edu.au]
Sent: Tuesday, July 25, 2000 11:41 PM
To: 'HistoNet'
Subject: Kappa and Lambda IHC


Hello all,

Was wondering if any kind souls out there could give me some advice on Kappa
and Lambda staining on formalin fixed paraffin embedded human tissue.
Currently we use tonsil as a control and use HIER by pressure cooking for 2
minutes in citrate buffer (pH 6.0).  At the moment we get some background
staining.  I have heard that some people use enzyme digestion for these
antibodies...any comments??

Thanks in advance.

Melanie Trivett
Peter MacCallum Cancer Institute
Melbourne
Australia