Dr. Fujita says he reasoned that an even more powerful immunosuppressant chemical ought to be present in a group of Asian fungi known in Chinese and Japanese as "winter-insect-summer-plants." These fungi attack insects in the winter with their chemical arsenal. By summertime, the insect is dead and its corpse has been transformed into a vessel for the blooming fungus. Ironically, the same properties that make the chemical deadly in the insect world may also have a helpful side for people suffering from certain autoimmune diseases, in which an overactive immune-system response causes the body to attack its own cells.
Wednesday, June 23, 2010
Mathis emphasized that one should not take away from these mouse studies "that mice or humans can 'catch' an autoimmune disease or arthritis," she says. She added that the better way to think about it is that individuals have varying degrees of genetic susceptibility, and when exposed to certain environmental factors may then go on to develop disease. "It's really an interaction between genetics and environment," Mathis says.
Monday, June 21, 2010
Thursday, June 17, 2010
In his search to explain the phenomenon, Dr. Petty knew to look for a metabolic pathway ormechanism with two characteristics. It had to "dial down" the intensity of the normal immune response, an action needed so that a pregnant woman does not reject the fetus, which has proteins from the father that are "foreign" to the mother. At the same time, such a mechanism must support cell growth needed by the developing fetus.
The activity of the enzyme pyruvate kinase–and its product, pyruvate–fills both roles: promoting cell growth while modifying the immune response. Because pyruvate kinase activity is depressed duringpregnancy, cell metabolism supports an increased production of lipids, carbohydrates, amino acids, and other substances that support cell growth.
The gene in question encodes an enzyme called sialic acid acetylesterase or SIAE, which regulates the activity of the immune system’s antibody-producing B cells. About 2 percent to 3 percent of people with autoimmune disorders have defects in the enzyme that allow B cells to run amok and make antibodies that attack the body, a team led by Shiv Pillai of Massachusetts General Hospital in Charlestown and Harvard Medical School reports online June 16 inNature.
“It’s a seminal paper because it is so applicable to a wide variety of autoimmune diseases, says Judy Cho, a Yale geneticist not associated with the study. The finding suggests that enhancing the enzyme’s activity could help treat disease in people with autoimmune disorders.
Tuesday, June 15, 2010
Virus infection may trigger unusual immune cells to attack the brain and spinal cord in multiple sclerosis
The authors explained that it's possible that multiple viruses could influence susceptibility to multiple sclerosis. The ability of any particular virus to contribute to the disease could depend on an individual's own repertoire of other predisposing genes, exposure to other predisposing environmental factors, and the random chance that T cells had been generated that recognize a myelin protein and a pathogen.
Receptors on T cells are randomly generated during their development. This observation helps explain why multiple sclerosis is partly a matter of chance. Some people with a genetic predisposition and environmental exposure develop the disease, while others with similar genetic predisposition and environmental exposure do not.
"We saw significant improvements in these adolescents' physical symptoms and coping strategies following treatment," said Ronald Blount, professor of clinical psychology at UGA and an author of the study. "Parents, who were also involved in the study, reported reductions in catastrophic thoughts related to their daughters' pain and improved behavioral reactions related to their daughters' physical symptoms. We aimed to teach parents to become coaches for their daughters to help them better manage their symptoms."
Monday, June 7, 2010
Women who consumed the most protein were at more than triple the risk of being diagnosed with IBD, the researchers found; animal protein accounted for most of the risk. Risk was specifically associated with high intake of meat and fish, but not with dairy products or eggs.
While experts have long suspected that diet might play a role in inflammatory bowel disease, Carbonnel and his colleagues note, the only links identified previously were with eating a lot of fats and certain kinds of sugars. Those studies were more prone to error than forward-looking or prospective studies like the current investigation. There have also been several studies linking vitamin D deficiency to IBD.
Meat could contribute to inflammatory bowel disease risk because digestion of animal protein produces many potentially toxic "end products," such as hydrogen sulfide and ammonia, the researchers note. Also, Carbonnel pointed out, a high-protein diet could alter the mix of bacteria that live in the colon.
Thursday, June 3, 2010
"It might not be possible for most of us to get breast milk from the tap," said Gerald Weissmann, M.D., Editor-in-Chief of the FASEB Journal, "but we can still benefit from some of the life-supporting substances it carries. This research shows that the relationship between humans and microbes can be beneficial for both. The Lactobacillus finds a new home, and we're no longer up tight."