FIGURE 3.

Cytokine mRNA induction and MIP-1β generation by LAD2 cells stimulated with cys-LTs. A, real-time PCR showing relative levels of MIP-1β, MCP-1, IL-5, IL-8, and TNFα transcript expression by LAD2 cells stimulated with 100 nm LTD₄ or LTE₄ for 2 h. Data are mean ± S.E. from three experiments. B, dose-dependent effect of LTE₄ on MIP-1β secretion by LAD2 cells stimulated for 6 h with the indicated concentrations of cys-LTs. Results are mean ± S.E. from three experiments. C, MIP-1β concentrations were measured in supernatants collected from cells after 6 h of stimulation with LTD₄ (100 nm), LTE₄ (100 nm), or anti-IgE (1 μg/ml) as a positive control. D, effect of pretreatment with MK571 (1 μm) on MIP-1β generation by cells stimulated with LTD₄ (100 nm), or LTE₄ (100 nm) for 6 h. Results are expressed as the mean ± S.D. from the three experiments performed. * and ** indicate p < 0.05 and <0.01, respectively, relative to the control in B and C and relative to the samples without MK571 in D.