Figure 2.

Time course of peripheral blood mononuclear cell proliferation

Peripheral blood mononuclear cells were cultured with or without 25 μm tryptophan for the time indicated and [³H]thymidine incorporation was then determined as described in Methods. ○, tryptophan; •, nil. Dashed lines, after culturing without tryptophan for the time indicated, tryptophan was added to 25 μm followed by culture for the time indicated and [³H]thymidine incorporation was then determined. ▿, 24 h; ▾, 48 h; □, 72 h. Data represent the mean ±s.d. of three separate experiments with quadruplicate assay.