tokens: T cells isolated by nylon wool filtration specifically bind 6.7 +/- 0.2 fmol of dexamethasone per million cells ( equivalent to 4000 +/- 200 receptors per cell ) , whereas T cells isolated by E-rosette sedimentation bind 12.0 +/- 0.7 fmol of dexamethasone per million cells ( equivalent to 7200 +/- 400 receptors per cell ) .