Expression of CD117 and platelet-derived growth factor receptor α in patients with alopecia areata.

Background: Alopecia areata is a disease of uncertain, probably autoimmune etiology. The role of growth factors like platelet-derived growth factor and C-kit (CD117) in alopecia areata is unknown.

Aims: To compare the expression of CD117 and platelet-derived growth factor receptor α in tissue samples of alopecia areata and normal controls.

Methods: Thirty biopsy samples of alopecia areata and eighteen normal control samples were included in this cross-sectional study. Immunohistochemistry was done to detect the expression of CD117 and platelet-derived growth factor receptor α in cases and controls. The mean percentage of follicles expressing CD117 and platelet-derived growth factor receptor α was compared among cases and controls.

Results: The mean number of follicles expressing CD117 in anagen and catagen hairs differed significantly among cases and controls. The extent and intensity of staining with platelet-derived growth factor receptor α correlated significantly with the severity of alopecia areata based on the severity of alopecia tool score.

Limitations: Confirmation of the expression pattern of molecules observed in immunohistochemistry with western blot or polymerase chain reaction would have strengthened the report.

Conclusions: The expression of CD117 varied in cases and controls. The expression of platelet-derived growth factor receptor α correlated with the severity of the disease. This could explain how platelet-rich plasma works in the treatment of alopecia areata. Further studies are required to explore the role of these molecules in autoimmune pathogenesis.