Fig. 5.
Activation of MAPK/NF-κB/MMP-9 by dual-tropic HIV-1SF33, R5-tropic HIV-1SF170 and X4-tropic HIV-192UG029 in polarized tonsil epithelial cells. (a) Polarized tonsil epithelial cells were exposed to dual-tropic HIV-1SF33, R5-tropic HIV-1SF170 or X4-tropic HIV-192UG029 (Uganda) for 5 days. Untreated cells and HIV-1∆env were used as controls. The TER of polarized cells was measured on day 5. Error bars indicate sem (n=3). *P<0.001, compared to the control group. (b) The cells were dissociated from inserts and used for evaluation of MAPK/ERK1/2 and NF-κB activation by Western blot assay. (c) The culture medium was collected and examined for MMP-9 expression and activity by Western blot and gelatine zymograpy, respectively. Two independent experiments showed similar outcome.