PMC9520325_01
Blisters and erosions in the oral cavity of our patient.
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F1
Dermatological examination revealed erosions in the aforementioned areas and in the nasal mucosa (Figure 1).
(A) Histology showing subepidermal blisters and lymphocytic infiltrates with rare eosinophils in the superficial dermis. (B) Direct immunofluorescence revealing IgG deposits along the dermal-epithelial junction. (C) Salt-split skin indirect immunofluorescence showing IgG deposits along the floor of the blister. (D) Indirect immunofluorescence test using recombinant laminin 332 expressed in human HEK293 cells revealing the presence of anti-laminin 332 antibodies in the patient's serum.
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F2
Histopathological examination showed subepidermal blisters and lymphocytic infiltrates with rare eosinophils in the superficial dermis (Figure 2A). IgG along the basement membrane (Figure 2B). Commercial ELISA kits (Euroimmun, Padova, Italy) did not reveal antibodies against BP230 and BP180 antigens. Indirect immunofluorescence on salt split skin confirmed the linear IgG deposition along the blister floor (Figure 2C). We demonstrated the presence of anti-laminin 332 antibodies in the patient's serum using a sensitive and highly specific indirect IF test using recombinant laminin 332 expressed in human HEK293 cells, with all laminin subunits alpha3, beta3, and gamma2 (Figure 2D), as already performed in other studies.