Elevated IL-37 in TB patients and induction of IL-37 in response to Mtb infection.

<p><b>(A)</b> ELISA detection the abundance of IL-37 in the sera from healthy donors (HD) (n = 24) and TB patients (TB) (n = 24). Data are mean±SEM. Student’ <i>t</i> test was used for statistical analysis. <b>(B)</b> Western blot detection of IL-37 in the lysates of PBMC from HD (n = 7) and TB (n = 7). <b>(C)</b> Quantification and statistical analysis of the relative density (mean gray value) of IL-37/β-actin as shown in <b>(B)</b>. Data are mean±SEM. Student’ <i>t</i> test was used for statistical analysis. <b>(D)</b> Induction of IL-37 transcripts measured by qRT-PCR in human THP-1 cells infected with H37Rv at MOI 5 for indicated time. <b>(E)</b> Secretion of IL-37 protein measured by ELISA in PMA-differentiated human THP-1 cells infected with H37Rv at indicated MOI for 24 h. Data <b>(D-E)</b> are mean±SEM and representative of 3 independent experiments. <b>(F)</b> Kinetics of IL-37 production measured by ELISA in the lung of WT and IL-37-Tg mice infected with BCG. Results are mean±SEM and are pooled from two independent experiments (n = 7 or 8 for each time point). *, p<0.05; **, p<0.01.