Figure 5. RXRα negatively regulates type I IFN expression in immortalized and primary BMMs.

(a,b) J2 BMMs were pretreated with DMSO, 9cRA (100 nM) or HX531 (1 μM) for 16 h and subsequently transfected with 1 μg ml⁻¹ polyI:C for indicated time. The mRNA expression of Ifnβ (a) and Ifnα4 (b) were measured by qPCR. (c) Immunoblot of RXRα in the WT and RXRa−/− BMMs that pretreated with DMSO or 9cRA (100 nM) for 24 h. (d-f) WT and Rxra−/− BMMs pretreated with DMSO or 9cRA (100 nM) for 24 h, then the cells were transfected with 1 μg ml⁻¹ polyI:C for 2h. Ifnβ (d) and Ifna4 (e) mRNA expression were measured by qPCR. IFNβ protein level were detected by enzyme-linked immunosorbent assay after 8 h polyI:C transfection. Data of a,b and d-f are shown as mean ± s.d. (n = 3) of one representative experiment, similar results were obtained in three independent experiments. *P< 0.05 and **P<0.01 (Student's t-test). Data of c are representative of three independent experiments. See also Supplementary Fig. 7 of uncropped blot of c.