shRNA targeting caspase-3 inhibits apoptosis and cell detachment induced by Pemphigus Vulgaris autoantibodies

Abstract

Pemphigus is an organ-specific autoimmune disease that affects the skin and mucous membranes. It is induced by the deposition of pemphigus IgG autoantibodies, which mainly target Dsg1 and 3 and cause a loss of cell adhesion in a phenomenon known as acantholysis, and clinically is reflected as intraepidermal blistering. The present work assessed the effect of pemphigus vulgaris IgG (PV-IgG) on cell adhesion and caspase 3- dependent apoptosis in HaCaT cells. The expression of caspase-3 induced by PV-IgG was silenced in cells pre-treated with caspase 3-shRNA. PV-IgG induced cell detachment and apoptotic changes as demonstrated by the annexin-FITC assays. Treatment of cell cultures with normal IgG (control; N-IgG) did not have relevant effects on the aforementioned parameters. Then, the effect of PV-IgG on cells previously treated with shRNA was tested. The results demonstrated that shRNA reduced apoptotic features and the relative expression of caspase-3 measured by qRT-PCR, which showed a decrease of 96%. In conclusion shRNA prevented cell detachment and apoptosis of HaCaT cells induced by PV-IgG. The presented results further our understanding of the molecular pathophysiologic mechanisms involved in pemphigus diseases.