MX1 and systemic lupus erythematosus: We used the pristane-induced lupus model in C57BL/6 mice carrying an intact Mx1 allele (B6.A2G-Mx1) [49,50,51,52] and B6.A2G-Mx1-Ifnlr1−/− mice deficient in functional IFN-λ receptors [53].