A new mutant mouse that cannot sustain immune responses is described in a study published online this week in Nature Immunology.
"Elektra" mice are a special mutant strain that readily succumb to bacterial and viral infections. Immune cells in Elektra mice develop normally and become activated upon infection; however, unlike immune cells in normal mice, Elektra immune cells die soon after their activation. As a result, Elektra mice are immunodeficient, and die from any infection.
Bruce Beutler and colleagues identify a mutation in the gene called Schlafen-2 as responsible for the immune defect seen in Elektra mice. How the protein encoded by Schlafen-2 promotes survival of activated immune cells is not yet known. The scientists note, however, that several pox viruses encode Schlafen-like genes, suggesting that viruses might have appropriated a similar activity to perpetuate survival of viral-infected host cells.