Toll-like receptors and IFN-alpha: partners in autoimmunity.

Many autoimmune diseases are thought to be precipitated by viral infections. In this issue of the JCI, Lang et al. demonstrate that, in a mouse model of autoimmune hepatitis, viral infections not only trigger expansion of self-reactive T cells but also activate antigen-presenting cells through TLR stimulation (see the related article beginning on page 2456). Activated cells then secrete IFN-alpha and TNF-alpha, which trigger tissue release of chemokines that attract self-reactive CD8+ T cells, ultimately leading to liver damage.