Amphiregulin in Psoriasis
Title: Amphiregulin causes functional downregulation
of adherens junctions in psoriasis.
Authors: Chung E, et al.
Publication: J Invest Dermatol. 2005 Jun;124(6):1134-40.
Over-expression of amphiregulin (AR, a type of growth factor)
has been linked to psoriasis in mouse and man. Since psoriasis
is marked with over-production of keratin, loss of skin barrier
function, and infiltration of inflammatory cells into the epidermis
and dermis layers of the skin, the authors thought that amphiregulin
might play a role.
The authors found that there is significant reduction of functional
E-cadherin (a membrane protein that is involved in cell adhesion)
in psoriatic lesions of both mouse model and patients with psoriasis.
When compared with normal skin, psoriatic lesions have lower
levels of E-cadherin and appearance of a protein fragment outside
the cells with a weight of 80 kilodaltons. The authors also found
decreased immunological and histological staining of E-cadherin
in the basal epidermis of human psoriatic lesions.
When the authors administer amphiregulin to the tissue, they
found enhanced movement of human neutrophils (a type of white
blood cells that destroys microorganisms) into the epithelial
layer. No such effect was found with growth factor alpha, suggesting
a specific role for amphiregulin or AR in the disease development