Fig. 1.

Induction of CD23 expression in 1321N1 astrocytoma cells by various cytokines. Cells were treated for 48 hr with various doses of interferon-γ (IFN-γ) (1–1000 U/ml) alone or in combination with interleukin-1β (Il-1β) (1 ng/ml), and/or tumor necrosis factor α (TNF-α) (10 ng/ml). CD23-positive cells were detected by immunocytochemical methods. Results are expressed as the mean percentage of CD23-positive cells ± SEM in three independent experiments. *Significantly different from cells with culture medium alone (p < 0.01); **significantly different from cells treated with IFN-γ alone (p < 0.05); two-tailed t test.