Certain families produce higher levels of a specific molecule, called interferon-alpha, that primes the bodys immune system to turn on, and in some cases initiate an autoimmune attack on itself, according to new research from Hospital for Special Surgery in New York City.

Our immune system is able to defeat disease-causing viruses and bacteria every day using chemical weapons, like interferon-alpha, that have been honed over time. But like anything else, we can have too much of a good thing.

Using blood samples from two large repositories, rheumatologist Mary K. Crow, M.D., and her colleagues at Hospital for Special Surgery compared 266 patients with systemic lupus erythematosus (SLE), an autoimmune disease, with 405 of their healthy relatives. Specifically, Dr. Crow, who is director of Rheumatology Research and associate chief of the Division of Rheumatology at Hospital for Special Surgery, and her team were looking at levels of interferon-alpha. The researchers found that when an SLE patient had high blood levels, so did many of their healthy first degree family members. There was a genetic link.

The study, which is now online in advance of print, will be in the September issue of Genes and Immunity.

There were a number of first degree relatives of patients with SLE that had high interferon-alpha levels, says Timothy Niewold, M.D., first author of the study and a former rheumatology fellow at Hospital for Special Surgery. But otherwise, those family members looked and felt perfectly fine. All of their diagnostics were normal.

Our immune system works by distinguishing self from non-self, so that it preferentially attacks foreign microbes. Interferon-alpha is normally a helpful molecule in this regard, leading the fight against invading viruses. Genes producing high levels of interferon-alpha have probably been selected over time to help fight infection. But high levels of interferon-alpha in some individuals ma
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Contact: Tracy Hickenbottom
hickenbottomt@hss.edu
212-606-1197
Hospital for Special Surgery
27-Jul-2007