Figure 7. Influence of cell type on promoter-directed reporter gene expression. Promoter constructs were transfected into wMC (rat Müller cells; red), NIH/3T3 (mouse fibroblasts; green), or Neuro-2a (mouse neuroblastoma; blue). All values were normalized to pFUGW and plotted according to percent enhanced green fluorescent protein (eGFP) positive cells (A) or mean fluorescence intensities (MFI; B). A: Percent eGFP expressing cells are plotted for control (pFUGW, pFTMGW, and VMR2) and xperimental (GLUL 500 ± untranslated region (UTR), S100B 500±UTR, and RLBP1 500±UTR) constructs. Note that transfection efficiency of Neuro-2a cells was significantly higher overall (95% positive cells versus ~20% for wMC and NIH/3T3), which, consequently, resulted in significantly higher expression in the pFTM3GW control. Nevertheless, when normalized to pFUGW, cell type had little influence on the relative percentage of cells that express eGFP, with the exception of a doubling in the number of NIH/3T3 cells transfected with the RLBP1 500+UTR construct. B: Though absolute eGFP expression levels were quite different for the three cell types examined, similar results to those in (A) were obtained when the MFIs were normalized to pFUGW. Perhaps an overall trend is noticeable; NIH/3T3 cells (green) tended to offer slightly higher relative eGFP expression, and Neuro-2a cells (blue) tended to exhibit slightly lower eGFP expression than that observed for wMC Müller cells (red). No TFX indicates no transfection. Error bars represent 1 standard deviation.