TABLE 1.

Estimation of amounts of free TGFβ2 in binding assays^a

TGFβ2 concn	Total TGFβ2 amt (fmol)	Mean change in fluorescence intensity (arbitrary units)	Relative bound amt (B′)	Estimated free amt (fmol) (F′)	B′/F′
1 pM	0.1	70	100	0.0-0.1
10 pM	1	119	170	0.83-1	170-205
100 pM	10	178	254	9.75-10	25.4-26.0
1 nM	100	301	430	99.6-100	≈4.32
10 nM	1,000	538	769	999-1,000	≈0.77
100 nM	10,000	519	750	9,999-10,000	≈0.075

^aTGFβ2 concentrations and mean change in fluorescence intensity intensity numbers were derived from Fig. 1E. Relative amounts of bound TGFβ2 (B′) were calculated under the condition that the amount of bound TGFβ2 was 100 when the TGFβ2 concentration was 1 pM.