FIG 1.

(A) HPLC chromatogram of the lyophilized cell-free supernatant of B. dendrobatidis cells (JEL197) showing the presence of tryptophan, Kyn, and MTA. Absorbance is reported as micro-absorbance units (μAU). (B and C) Inhibition of PHA-stimulated X. laevis spleen cells by MTA. (B) Data from one representative of five similar experiments. X. laevis splenocytes were cultured alone or with PHA. PHA-stimulated cells were incubated with increasing concentrations of MTA, as shown. (C) Percent inhibition of growth at each concentration (n = 4 or 5 experiments at each concentration). (D and E) Inhibition of Jurkat T cells by MTA. (D) One representative experiment (seven total) showing inhibition of growth measured as the reduction of MTT at 570 nm. The positive control (Pos.) was medium alone, and the negative control (Neg.) was treated with etoposide (Etop). OD₅₇₀, optical density at 570 nm. (E) Summary of data from seven experiments reported as percent inhibition of growth. For all panels, error bars show standard errors, and the indicated treatments were significantly different from the positive control (PHA alone for splenocytes and medium alone for Jurkat cells). *, P < 0.05; **, P < 0.01 (determined by one-way analysis of variance with a Tukey post hoc test).