RE: Intracellular cytokines

Calman Prussin (Calman_Prussin@d10.niaid.pc.niaid.nih.gov)
Tue, 12 Sep 95 21:12:24 EST

Although I agree monensin is not the perfect blocker of intracellular
transport, I think your response is a bit exaggerated. What toxicity data
are you citing? The Jung paper demonstrated monensin toxicity only after 16
hours. Both monensin and BFA need only be in the culture for 2-4 hours for
maximal effect (my data and others). Also consider that the strong stimuli
(PMA/ionomycin) that are often used to effect sufficient cytokine
expression are also causing cell death. A couple of hours of monensin may
not be the largest perturbation in the system.

I have not compared a large number of cytokines, but for huIL-2 and IFN I
do not see a significant difference in the mean fluorescence intensity or
% positives between BFA and monensin.

The main reason for using monensin in the past was that it was dramatically
cheaper. Sigma now sells BFA at a reasonable price. It is worth having a
through discussion of the relative merits of each, as I am eager to switch
to a better reagent. I look forward to hearing from you to substantiate
your statement.

Intracellularly Backed Up in Bethesda,

Calman Prussin
Allergic Diseases Section
NIAID/ NIH
calman@nih.gov

------------------------ Forwarded Message -----------------------

Jonni S. Moore wrote:

In response to your questions concerning intracellular cytokine staining:

1. Brefeldin A is MUCH better than monensin. It is less toxic and
exerts its effects in a shorter time frame--we add it to cultures typically
4 hours before staining.

2. Pharmingen is marketing a line of anti-cytokine antibodies that they
claim are optimized for intracellular staining. We have used their
FITC-anti-mouse interferon gamma and PE-anti-mouse IL4 with success.
Several other companies have labelled anti-cytokine antibodies, but they
may not be suitable for intracellular use. You'll just have to try them.