Figure 6. 1-L-MT serves as tryptophan replacement for Toxoplasma gondii and human T cells.

(A) Toxoplasma gondii growth in 86HG39 cells and (B) human T cell growth was observed in tryptophan-depleted medium in the presence of different amounts of L-tryptophan or 1-L-MT (0–300 µg/mL for T. gondii and 0–75 µg/mL for T cells). Parasites as well as human cells were unable to proliferate in the absence of tryptophan, but retained their ability to proliferate in the presence of L-tryptophan and, importantly, of 1-L-MT. Data are given as T. gondii growth, measured by [³H] uracil incorporation and as T-cell proliferation, measured by [³H] thymidine incorporation +/− SEM of three (T cells) or four (parasites) independent experiments with each experiment performed in triplicates. * = increased growth as compared to the negative control (p<0.05). ** = significant decrease as compared to the 0,75 µg/mL tryptophan group (p<0.05).