Levels of TNF-alpha in culture supernatants.

<p>TNF-alpha was assayed by ELISA in supernatants of PBMC cultured for 48 h in the absence of any stimulus and in the presence of <i>T. cruzi</i> antigen, LPS and PHA. <b>A.</b> Subjects were grouped according to positive or negative serology; *p = 0.0003 (Mann-Whitney test). <b>B.</b> Subjects were grouped according to the cardiac or indeterminate form and negative serology: Cardiac x negative to medium: p = 0.0002; cardiac x negative to LPS stimulation: p = 0.005; indeterminate x negative to PHA: p = 0.03; cardiac x indeterminate to medium: p = 0.01; to LPS: p = 0.005; to <i>T. cruzi</i> antigens: p = 0.01 (Mann-Whitney test). Results are expressed as pg/mL. The horizontal line indicates the median, bars the 25% and 75% percentiles, and vertical lines the 10% and 90% percentiles.