What is the BEST biopsy technique for mucous membrane pemphigoid?

For vesiculobullous/autoimmune diseases (MMP, pemphigus), a PERILESIONAL biopsy is taken from ADJACENT to the lesion — the lesion itself often ulcerates/necroses, providing poor tissue for diagnosis. The perilesional tissue is intact epithelium where immunofluorescence can show IgG/IgA/C3 deposition along the BMZ. DIF (direct immunofluorescence) is the gold standard.