We are using the L929 fibriblast -based assay to measure TNF in rat
plasma. The assay has worked perfectly in the past but we are now
getting some odd results. The standard curve works fine showing
normal cytotoxicity. Cytoxicity is measured using MTT. Therefore,
TNF-containing samples should decrease the final absorbance. However,
samples in the last few assays have increased the absorbance.
Any ideas?
Simon Worrall
Alcohol Research Unit,
Dept of Biochemistry,
University of Queensland,
Australia.
