Abstract
In mammals, males and females show marked differences in immune responses. Males are globally more sensitive to infectious diseases while females are more susceptible to systemic autoimmunity. X-chromosome inactivation (XCI), the epigenetic mechanism that ensures the silencing of one X in females, may participate in these sex-biases. Here, we perturbed the expression of the trigger of XCI, the non-coding RNA Xist, in female mice. This resulted in reactivation of genes on the inactive X, including members of the Toll-like receptor 7 (TLR7) signalling pathway, in monocyte/macrophages, dendritic and B cells. Consequently, female mice spontaneously developed inflammatory signs typical of lupus, including anti-nucleic acid autoantibodies, increased frequencies of age-associated and germinal centre B cells and expansion of monocyte/macrophages and dendritic cells. Mechanistically, TLR7 signalling is dysregulated in macrophages, which leads to sustained expression of target genes upon stimulation. These findings provide a direct link between maintenance of XCI and female-biased autoimmune manifestations and highlight altered XCI as a cause of autoimmunity.
Teaser Perturbation of X-chromosome inactivation, a female-specific process, induces signs of lupus, a disease that mostly affects women.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
Significant results describing into more details the autoimmune phenotype have been added. The author list has changed.