Figure 2.

IFN-λ4 increases expression of pro-inflammatory cytokines when present during the differentiation of THP-1-derived M1 macrophage-like cells. (A) Schematic representation of the two strategies (postand pretreatment) used to examine the effect of IFN-λ4 on macrophage-like cells. (B) IFN-λ4 significantly increased the secretion of TNF-α, IL-6, and IL-12 in the pretreatment strategy (at a higher dose) showing the mean and _SD. (C) MX dynamin-like GTPase 1 (Mx1) expression in A549 cells treated for 24 h with graded doses of IFN-λ4. The data from THP-1-derived macrophage-like cells activated toward an M1 phenotype by LPS treatment. The data are from three biological replicates show the mean of technical replicates with error bars showing the _SD (a significant difference, P < 0.01, in the expression of Mx1 between 2 and 6 μg/ml of recombinant IFN-λ4 was observed). (D) IFN-λ4 and IFN-λ may activate overlapping pathways. THP-1-derived macrophage-like cells differentiated with ±IFN-λ4 were activated to an M1 phenotype by using LPS and ±IFN-λ. The data are from three biological replicates showing the mean and _SD. For (B), (C), and (D) *P < 0.05; **P < 0.01; ns, not significant