Fig. 3
Effects of TMPRSS2 overexpression on HLA class I expression, the antigen presentation machinery (APM) and interferon (IFN) signaling in TMPRSS2-transfected cells and their influence on natural killer (NK) cell function. A: Flow cytometry was used to assess HLA-I surface expression in TMPRSS2 transfectants and mock control MCF-7 and EA.Hy926 cells as described in the Methods. The results are displayed as a histograms with the mean fluorescence intensity (MFI) of HLA-ABC (n = 3). B: The expression of major HLA-I APM components in TMPRSS2 transfectants was evaluated using qPCR as described in the Methods. C: The cytotoxic activity of NK cells from three different donors against TMPRSS2low and TMPRSS2high MCF-7 cells was evaluated using a CD107a degranulation assay. Data are shown as mean ± SE of CD107a degranulation upon normalization to the mock-transfected cells. D: TMPRSS2 transfectants were examined by qPCR for the expression of components of the IFN as well as JAK-STAT signaling pathways. The results are shown as an x-fold induction in the expression of these signaling components in TMPRSS2 transfectants relative to mock controls. E: Representative Western blot analyses of TMPRSS2high and mock-transfected using antibodies directed against IRF1, IRF27, STAT1, pSTAT1 and STAT2. Staining with an anti-ACTB antibody served as a loading control