Table 1. TGF-β in a T cell culture supernatant was measured by the 293T-caga-CD32-CD86-caga bioassay (TGF-β activity), by ELISA without acidification (the 25 kDa free TGF-β dimer), and by ELISA after acidification ( “total TGF-β”).

TGF-β in culture supernatant
293T-(caga)12-Luc	ELISA	ELISA
bioassay	without acidification	after acidification
(activity)	(25 kDa free dimer)	(“total”)
∼200 pg/ml	10 pg/ml	486 pg/ml