Enzyme Shortage May Lead to Lupus
By Nathan Seppa
Just as the garbage that collected in streets during the Middle Ages sustained rats and the bubonic plague they spread, DNA piling up in dead or dying cells creates an environment conducive to systemic lupus erythematosus, or lupus. Working with an enzyme that clears away such cellular debris, scientists in Germany have opened a new line of research into this autoimmune disease.
The body comes equipped with several proteins that chop up and clear away trash DNA. One of them, an enzyme called DNase I, appears less active in many lupus patients than in healthy people. When too much debris accumulates, immune cells identify it as an antigen—a foreign body to be destroyed—and make antibodies against it. This can engender a chain reaction of wanton cell death. The body offers no defense because its own soldiers, immune cells, orchestrate the killing.