FIG. 5.

The secretion of TNF-α and IL-10 in U937 cells infected with recombinant M. smegmatis strains measured by ELISA and reverse transcription-polymerase chain reaction (RT-PCR). (A) U937 cells were infected at an MOI of 10:1 with M. smegmatis containing vector only (□), PE_PGRS 17 (▪) and incubated for 24 h. Culture sediments were used to extract RNA, followed by semiquantitative RT-PCR to demonstrate the transcriptional levels of TNF-α and IL-10. (B, C) Culture supernatants were collected at 24 h after infection and used to quantify the production of TNF-α and IL-10 by the ELISA kit.