FIGURE 3.

Pam₃CSK₄ binds the surface of cells expressing wild type TLR2 but does not bind cells expressing TLR2 I319D. The 293 cells transiently transfected with human TLR2 or TLR2 I319D mutant were incubated for 15 min at 37 °C with A₄₈₈-Pam₃CSK₄-sCD14 (80 ng/ml A₄₈₈-Pam₃CSK₄, 1 μg/ml sCD14) complexes and then stained for surface expressed FLAG-tagged TLR2 proteins. In addition, the cells were stained for the nucleus by the addition of 4′,6′-diamino-2-phenylindole (DAPI) in the mounting medium. CCD images for the fluorescence of A₄₈₈-Pam₃CSK₄, TLR2 (wild type (wt) or I319D mutant), and the nucleus are shown for representative cells as well as the merged images.