Quality of Indo-1

Dr Stephen Young (steve@rheuma.bham.ac.uk)
Sat, 5 Dec 92 20:00:58 GMT

WE recently spent some months trying to establish indo-1 Ca measurements on our
Coulter Epics Elite to no avail - at least we could get some loading into PBMC
but the fluorescence responses to lectin and anti-CD3 were very poor - ionomycin
responses were OK but not of much interest to us obviously. During this time we were
using Indo-1 AM from Sigma and PHA-P from the same source. A few weeks back we bought
some Indo-1 from Molecular Probes and the effect was remarkable - much greater intensity
and much less heterogenous loading. Anti-CD3 and CD2 responses were much much better and
when we got some PHA-P from DIFCO we could also get a decent response.

Although we were very careful with the original Indo from Sigma - using dry DMSO to
dissolve and storing dessicated etc we feel that the problem could have been in the
material supplied.

I'm putting this is as a warning to others but also to see if else has had any similar
problems with sources of fluorescent indicators?

Steve Young
Dept of Rheumatology
University of Birmingham UK
Email to s.p.young@bham.ac.uk Voice: 021-414-6780