Effects of pemphigus vulgaris serum on expression of Dsg and MMP-9 in HaCaT cells

Abstract

Objective: To investigate the effect of pemphigus vulgaris (PV) serum on expression of Desmoglein (Dsg)1, Dsg3 and matrix metalloproteinase 9 (MMP) 9 in HaCaT cells, and its pathogenic role in acantholysis. Method: This study included four experimental groups, i.e., normal control group, healthy-serum group, PV-serum group, anti-Dsg3 monoclonal antibody group (positive group). Human HaCaT cells were cultured with high-glucose DMEM medium containing 5% PV serum, followed by extraction of RNA and protein for Q-PCR and Western Blot analyses, respectively. In addition, immunostaining was used to assess expression of Dsg1, Dsg3 and MMP-9 in keratinocytes. Results: In addition to elevations in expression levels of respective protein, culture of HaCaT cells with 5% PV-serum increased expression levels of mRNA for Dsg1, Dsg3 and MMP-9 by 432%, 402% and 402%, respectively. Likewise, incubation of HaCaT cells with anti-Dsg3 monoclonal antibody increased expression levels of mRNA for Dsg1, Dsg3 and MMP-9 by 495%, 488% and 604%, respectively (P<0.05 vs. normal control). Immunostaining showed that linear distribution of Dsg1 on cell surface was replaced with granular and clustered patterns on the cell surface and in the cytoplasm in keratinocytes cultured with PV-serum. Moreover, intensity of Dsg3 staining was decreased. Conclusions: PV serum increases expression levels of Dsg1, Dsg3 and MMP-9. The Dsg3 antibody can cause acantholysis by induction of endocytosis of Dsg1 protein by keratinocytes and reduction in antibody compensation.

Keywords

• pemphigus vulgaris
• mmp-9
• desmoglein
• endocytosis
• acanthosis