Cross-Linking Mast Cell Specific Gangliosides Stimulates the Release of Newly Formed Lipid Mediators and Newly Synthesized Cytokines

Figure 1

Cross-linking GD1b derived gangliosides by mAbAA4 induced Syk-dependent release of PGD₂ and PGE₂. For stimulation via FcεRI, RBL-2H3 cells and C4A2 Syk-negative cells were sensitized with IgE anti-TNP and stimulated with DNP₄₈-HSA (50 ng/mL). For FcεRI independent stimulation, the cells were incubated with calcium ionophore (0.1 μg/mL). To cross-link GD1b derived gangliosides, cells were incubated with mAbAA4 (1, 2.5, 5, and 10 μg/mL). Nonstimulated (NS) cells were used as negative controls. Culture supernatants were collected after 30 min of incubation to evaluate immediate release (a and c) or cells were incubated for 1 h and rinsed and cultured for an additional 3 h and culture supernatants were collected to evaluate delayed release (b and d). PGD₂ (a and b) and PGE₂ (c and d) were measured in the culture supernatant by EIA. Data is expressed as the mean ± SD of three independent experiments. between experimental samples and the nonstimulated (NS) cells. between experimental samples and FcεRI stimulated RBL-2H3 cells.

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