Effects of cellular stimulation with immune complexes and/or IL-5 on intracellular NGF and NT-3.

Eosinophils were suspended in RPMI 1640 medium supplemented with 10% DCS and incubated with medium alone or 20 μg/mL sIgA, serum IgA, or serum IgG for 1 hour at 4°C. Cells were then stimulated with the corresponding antihuman sIgA monoclonal antibody, goat antihuman IgA, or goat antihuman IgG and cultured in the absence (closed columns) or presence (open columns) of 25 ng/mL IL-5 at 37°C for 24 hours. After culture, cells were collected and lysed with 1% Triton-X and 3 freeze-thaw cycles. The amounts of NGF (A), NT-3 (B), and EDN (C) in cell lysates were measured by ELISA or RIA. The data show mean ± SEM from 3 experiments. *denotes significant difference from the values cultured with medium alone (None) (P < .05); †denotes significant difference from the values cultured with the same stimuli but without IL-5 (P < .05). ND, not determined.