Alternatively activated SP37A3 cells display a semimature phenotype. SP37A3 cells were differentiated as described (Figures 1,3). (A) Histograms represent expression of the markers indicated by immature (thin line), mature (thick line), and DEX-cotreated SP37A3 cells (filled histograms), and isotype-matched controls (dotted line). Graphs are representative of 3 independent experiments. (B-C) The relative mRNA expression level of genes encoding intracellular and transmembrane (B) and secreted (C) products was assessed by quantitative real-time PCR. The housekeeping gene ubiquitin C was used for internal normalization. Relative gene expression levels were determined by applying the comparative threshold cycle method. Data indicate fold changes in mRNA expression by mature and alternatively activated SP37A3 cells, respectively, versus immature cells (dashed line). Data represent the mean ± SEM of 3 to 6 experiments performed in duplicate. *Statistically significant differences in mRNA expression in mature or DEX-cotreated versus immature SP37A3 cells; statistically significant differences in mRNA expression in alternatively activated versus mature SP37A3 cells (*P < .05; #P < .05; **P < .01; ##P < .01; ***P < .001; ###P < .001).