Exposure of NLCs to rNAMPT activates signal transduction and expression of a panel of genes specifying the M2 phenotype. NLCs were exposed to rNAMPT (30 minutes, 37°C) before fixing, permeabilizing, and staining for phospho-ERK1/2 (A), p-STAT3 (B), and the p65 subunit of the NF-κB complex (C). DAPI (blue) was used to counterstain. Original magnification ×63. (D) Graphs show cumulative analyses plotting the mean values of all the fluorescence measurements for each independent experiment. At least 4 randomly chosen fields from different samples were analyzed after defining a region of interest. (E-F) Conventionally differentiated NLCs were treated with rNAMPT for 24 hours before RNA extraction and qRT-PCR analysis of the expression of IRF4 and IDO (E) or for a panel of chemokines/cytokines defining the M2 phenotype (F). (G) Increased expression of immunosuppressive chemokines/cytokines in cultured supernatants (n = 14) was confirmed at the protein level.