Fig. 4.

Tumour necrosis factor (TNF)-α (a) and interleukin (IL)-12 (b) levels in day 8 culture supernatants of infected macrophages. TNF-α levels of high responder (HR) macrophages infected with live (L) or live-opsonized (LO) Mycobacterium tuberculosis were significantly higher than corresponding values for low responders (LR). Interleukin (IL)-12 level of HR macrophages infected with L bacilli were also significantly higher than corresponding values for LR. However, following infection with LO bacilli, there was an increase in IL-12 levels of LR macrophages.