Monday, January 29, 2007
A report in the January issue of Nature magazine announces that one more step in understanding what may cause the body to attack itself in its war against autoimmune disease has been discovered by researchers at the Massachusetts Institute of Technology's Whitehead Institute, says the Autoimmune Related Diseases Association (AARDA), a national nonprofit patient advocacy organization.
What happens in certain cases to cause the body's immune system to go wild with an over reaction when it encounters invading viruses or bacteria, thus resulting in one or more autoimmune diseases--such as rheumatoid arthritis, lupus, multiple sclerosis, thyroid disease (Graves', Hashimoto's), juvenile (type 1) diabetes?
Researchers Richard Young and Alexander Marson, an M.D./Ph.D. student working in Young's laboratory, have reported discovering 30 genes that go awry in autoimmune diseases. According to Young, the regulatory T cells (called "T regs") that normally control the immune system may have genetic defects. In that case, the T regs protective powers are weakened.
The "brain" of the T regs is a protein called Foxp3. It can send the message to increase or decrease the production of other genes. Dr. Marson, study lead author, said, "We identified a set of roughly 30 genes that are clearly regulated by Foxp3 and, surprisingly, a lot of them are suppressed by Foxp3." Mutation in more of the genes, PTPN22, is associated with a number of autoimmune disorders. It is speculated that altering the Foxp3 gene might be one way to reach a cure of autoimmune diseases.
Two significant implications have emerged from this research. Marson commented, "One is that we've identified this core set of genes that are probably likely to play key roles in preventing autoimmune more disease." He added, "The second implication, which is maybe more long-term, is that we hope that identifying these targets will allow us to screen for drugs to mimic the function of Foxp3 and, thus, treat autoimmune disease."
Autoimmune disease pioneer Noel R. Rose, M.D., Director of the Johns Hopkins Center for Autoimmune Disease Research, says that treating autoimmune disorders will require enhancing either the number or effectiveness of regulatory T cells. He remarked that the MIT study is "certainly important in trying to understand how these regulatory T cells work." He cautions, "Whether this will have important functional implications, only time will tell."
Commenting on the study results, Virginia Ladd, AARDA president and executive director, observes, "The discovery adds weight to the reason why autoimmune diseases should be considered a disease category similar to the way that cancer is viewed rather than as singular diseases." She adds, "It also lends proof to the genetic connection among these diseases and an understanding as to why these diseases run in families."
Ms. Ladd points out that the public is unaware of the genetic connection among various autoimmune diseases, and patients are seldom queried by healthcare professionals regarding the family history in autoimmune disease. AARDA is pressing for federal legislation that would bring more awareness to autoimmune diseases and the fact that collectively they affect millions of Americans.
American Autoimmune Related Diseases Association (AARDA)
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