FIGURE 7.

Phagosomal acidification does not significantly affect the cytokine production to LPS and to heat-killed E. coli. A, BMDMs were incubated with P. falciparum IRBCs, synthetic hemozoin (sHz), or silica particles in the absence or presence of 100 ng/ml LPS. B, BMDMs were incubated with heat-killed E. coli at the ratios of 1:40 or 1:100 in the absence and presence of bafilomycin A₁ (BA1, 5 nm), theophylline (Th, 100 μm), and a mixture of bafilomycin A₁ (5 nm) and theophylline (100 μm). After 48 h, the TNF-α released into the culture medium was measured by ELISA. The results (mean values ± S.D.) shown are representative of three independent experiments each performed in duplicate. Arrowheads indicate values below the detection limit.