Fig. 1
Impact of CuO NMs and CuSO4 on the tight junction protein ZO-1 of the co-cultures. The Caco-2/Raji B (a) and Caco-2/HT29-MTX (b) co-cultures were exposed to cell culture medium (control) or 6.34 Cu µg/cm2 of CuO NMs and CuSO4 for 24 h, then fixed, and stained for the tight junction protein ZO-1 (green) and nucleus (blue). The images of extended focus were obtained with Zeiss LSM880 confocal microscope using the Zen program for data analysis. Red arrows indicate areas where there is a reduction in ZO-1 staining intensity. Scale bar = 20 µm. Representative images are shown