Role of mast cells and T-lymphocytes in pemphigus vulgaris: significance of CD44 and the c-kit gene product (CD117).

Molecular mechanisms underlying the pathophysiology of pemphigus vulgaris are still not clear. We aimed to determine the significance of detecting expression of some antigens that might be pivotal to the process, namely CD44 and CD117, in patients with active pemphigus vulgaris. Seventeen patients with active pemphigus vulgaris and 19 normal healthy controls were included in the study. The immunohistochemical results showed prominent expression of CD44 in 13 of the patients and CD117 in 9 of the patients with new blister formation. CD44 percentage values in peripheral T-lymphocytes were significantly higher in patients than controls, as detected by flow cytometry. In addition, there was a significant increase in a soluble form of c-kit in sera of patients with active pemphigus vulgaris compared to controls.