الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 150 |  |  |
| | | from | 150 | | |
Abstract
Alopecia areata (AA) is a complex autoimmune condition that causes nonscarring hair loss. There are different theories of autoimmunity as autoantibodies (IgG) affect the structure hair follicles in the anagen phase , Follicular inflammation mainly comprised of CD4+ and CD8+ T cells, increased expression of MHC-I and II and decrease in immune suppressive molecules (TGF- β, IGF-1, α-MSH) in hair follicles. Also, there is a higher expression of (ICAM-2, ELAM-1) in the perivascular and peribulbar zone of affected hair follicle (Adhesion molecules mediate trafficking of leukocytes to the the dermis).