FIGURE 4.
Cys-LT generation in response to purified Df extract and inhibition by mannose. A, Df extract was separated by chloroform/methanol extraction, evaporated, and reconstituted with RPMI 1640 medium. BMDCs were stimulated with the aqueous phase (AQ) and with unfractionated Df extract for 30 min. Results are means ± SEM from three experiments. B, The aqueous phase was then subjected to Con A affinity chromatography. The bound materials were eluted sequentially with elution buffer containing 0.1, 0.2, and 0.4 M of α-methyl mannoside/α-methyl glucoside and subsequently with 10% ethanol. Fractions were evaporated, reconstituted with RPMI 1640 medium, and added to day 8 BMDCs for a 30-min stimulation. Cys-LTs in the supernatant were measured by enzyme immunoassay. Values are means ± half-range (n = 2). Results are representative of three independent experiments. C and D, BMDCs were incubated with mannose for 30 min before stimulation with Df (C) or with the 0.2 M α-methyl mannoside/α-methyl glucoside elution fraction from Con A-purified Df (D). Values are means ± SEM from three experiments.