© 2003 Massachusetts Medical Society
Psoriatic skin and an immune synapse (Inset). (From T.S. Kupper, N Eng J Med, 349:1987–90, 2003.)
The red, cracked, and bleeding scales of psoriasis appear on the scalps, knees, elbows, and trunks of 2% of the global population. Psoriasis is more than the annoying skin condition portrayed in the 1960s-era advertisements bemoaning "the heartbreak of psoriasis." Understanding the immunological underpinnings of the disease has spawned new treatments and, in turn, response to treatments is revealing more about the pathology.
Although skin cells pile up abnormally in psoriasis, the root cause lies in an overzealous immune response. The telltale scales are not the cause, but the effect. "For years it was thought that in psoriasis, epidermal skin cell hyperproliferation was the key step. In the last decade, psoriasis has been recognized as due to overactive T cells," says Joel M. Gelfand, professor of dermatology at the ...
