Re your B27 questions:
We have been using the B-D B27 antibody and software for a year and a
half. We now process 200-400 samples per month as a reference center.
We initially compared the Lambda 1 product to the B-D product using
cytotoxicity as a "standard". Both antibodies were very good at
detection of B27 (all isoforms), but the B-D product had a higher degree
of false positives in cross-reaction to B7. However, the B-D antibody
with the software was so user-friendly (*and we got a deal*) that we
chose it to run as a screening assay. Borderline flourescence (5% of
samples with mean FL above or below the B-D cutoff) are then tested by
cytoxicity and RFLP to determine B27 vs B7. This works for us, quite well.
About 50% of our borderline cases turn out to be positive, but they
represent only 5% of our total B27 positives. I'm going to try to
publish this if I ever get the time to write it up properly.
I presume you are aware of the study last year by Ward (Cytometry
22:65) and Lingenfelter (Cytometry 22:146)
Good luck.
*************************************************************************
Denis Snider PhD, FCACB
Associate Professor
Dept. of Pathology
HSC-3N26
McMaster University
Hamilton, Ont. Canada