The release of IL-5, IL-13, IL-17, and interferon γ by nasal polyps dispersed cells (NPDC) was determined concomitantly with PLA2 messenger RNA expression, under SAE stimulation, with or without dexamethasone, as a regulator of PLA2 expression.
These findings indicated that IL-12 positively enhanced the generation of IL-21(+)IFN-γ(+)CD4(+) T cells having the features of both Tfh and Th1 cells in NP tissues.
Second, in order to investigate whether HLA class II expression is controlled at the pre- or post-transcriptional level, we studied the effect of interferon gamma (INF gamma) on epithelial cells in primary culture, which were derived from HLA class II negative and HLA class II positive nasal polyps.