Fig 2. mRNA expression, but no protein expression of the IL-39 subunits from human immune cells and keratinocytes.

(A) Purified human B cells were incubated with medium only or stimulated with LPS (1 μg/ml) or with a combination of LPS (1 μg/ml) and BAFF 50 ng/ml for 48 hrs. (B) HaCaT cells were incubated with medium or were stimulated with the TLR3 agonist Poly IC (30 μg/ml) for 48 hrs. (C) Polarized M0, M1 or M2 macrophages were subjected to quantitative RT-PCR analysis. (A-C) mRNA was extracted and transcript levels were measured by quantitative RT-PCR. Gene expression was normalized to β-glucoronidase levels and expressed as arbitrary units. (D) Intracellular FACS staining of B cells from (A). (E and F) Supernatants originating from cultures (A-C) or an IL-39 IgG1-Fc fusion protein were used in ELISAs where anti-p19 Ab was used for capturing of p19 and anti-EBI3 served as the secondary Ab. Graphs are representative of two independent experiments.