I have recently discovered this site. I have a question regarding=20
reagents. We have been testing the Caltag monoclonal kappa/lambda/cd19=20
antbody cocktail and comparing it to the same BD combination to try and=20
get a brighter CD19 signal for use in a clinical flow lab. I have=20
noticed a couple of cases in which the BD reagent shows no evidence of a =
light chain restriction but the Caltag reagent does (usually a very low=20
percentage, dim kappa). Has anyone else seen this? The population=20
could not be confirmed with polyclonal kappa and lambda from BD or Tago.
Eric,
We have been working through some of the issues about kappa/lambda =
staining over the last 12 months. We have found (and been told by others =
- principally Carlton Stewart) that choice of flourochrome is important. =
CD19 density on mature B cells is quite low so if you choose to use CD19 =
to select out your B cells you need the brightest flourochrome available =
to get good signal - CD19PE is the only way to go in this regard (thanks =
Carl !).
An excellent alternative to CD19 is to use CD20 - higher antigen density =
(also expressed on a small subset of peripheral T cells but at a low =
levels so this is never a problem in our hands). We now use a cocktail =
of polyclonal kappa or lambda FITC/CD20 PE/CD45 PerCP (all BD reagents) =
and are extremely happy with the results.
We haven't evaluated the Caltag reagent so I cannot make a direct =
comparison.
Hope this helps :-)
Peter Chapple
Peter MacCallum Cancer Institute
Mebourne AUSTRALIA