Immunofluorescence using natural or multi-species anti-Myc 9E10 antibodies. Hela cells expressing Myc- and GFP-tagged CLIP-170 were immuno-labeled using either the natural mouse monoclonal antibody Myc1-9E10 (a-c) or the recombinant human (d-f), rabbit (g-i) or mouse (j-l) versions of 9E10 scFv fused to Fc domains. 9E10 antibodies were detected using Cy3-labeled secondary antibodies. GFP fluorescence was directly imaged in the green channel (green, a, d, g, h). The overlays (c, f, u, j) show the GFP fluorescence in green and 9E10 detection of Myc-tagged proteins in red. Nuclei, stained using DAPI, are shown in blue. This experiment shows that recombinant 9E10 antibodies efficiently detect Myc tags by immunofluorescence and that the multi-species strategy can be used to change the species of natural antibodies. Bar = 20 μm.