February, 2001

by Mary J. Shomon

A report in the Jan. 30, 2001 issue of the Proceedings of the National Academy of Sciences has found a gene in mice that, when absent, causes an autoimmune disease that resembles systemic lupus erythematous (SLE, or lupus) in humans. The gene goes along with the lack of a particular enzyme, alpha-mannosidase II. Alpha-mannosidase II helps the body form carbohydate structures known as N-glycans. N-glycans help cells of the immune system distinguish between foreign invaders -- antigens -- that need to be attacked and defended against -- and the body's own tissues. Autoimmune disease involves the body's inability to distinguish between the foreign invadess and the body's own organs and tissues.

The researchers feel that this identifies an entirely new pathway by which autoimmune disease can occur, via a gene that controls the formation of carbohydrates.

The researchers also believe that carbohydrate research is not only applicable to lupus, but to other autoimmune conditions, and have labeled this emerging field "glycobiology."