(a, b) HeLa cells were transfected with plasmids encoding GFP, CFP-IRGMa, GFP-IRGMc or GFP-IRGMd, and after 24 h (a) or 48 h (b), stained with MTR. Percentages of positively transfected cells that were also MTR+ were then quantified. (c, d) Cells were transfected as in a, b, and after 24 h (c) or 48 h (d) the percentages of positively transfected cells that were also rounded by morphology were quantified. 