Fig. 1. Cystatin B inhibits the nuclear translocation of USTAT-1 in IFN-β treated MDM.
Uninfected MDM induced by IFN-β were assayed by immunofluorescence for cystatin B (green) and USTAT-1 (red). Blue fluorescent DAPI was used as nuclear stain. MDM expressing cystatin B before (1–3) and after IFN-β treatment (7–9), showed a cytoplasmic localization of STAT-1. In absence of cystatin B, USTAT-1 was retained in the cytoplasm of untreated MDM (4–6), but USTAT-1 was completely translocated to the nucleus in IFN-β treated MDM after silencing of cystatin B (10–12). Non-targeting siRNA was used as a control for the cystatin B silencing procedure (1–3 and 7–9). Confocal images were obtained on a Zeiss confocal microscope Axiovert 200M with a LSM 510, 40x. The results are representative of experiments performed using three different donors.
