Three Cases of Linear IgA/IgG Bullous Dermatosis Showing IgA and IgG Reactivity With Multiple Antigens, Particularly Laminin-332

Abstract

Our studies revealed that the 3 LAGBD cases showed prominent IgG and IgA reactivity with laminin-332, which was only rarely reported. In addition, all cases showed IgG and IgA reactivity with other multiple antigens, indicating the role of epitope-spreading mechanisms initiated from laminin-332. The significance of IgA antibodies to laminin-332 should be studied in larger cohorts of both LAGBD and linear IgA bullous dermatosis.

Linear IgA/IgG bullous dermatosis with autoantibodies directing the native and processed forms of BP180

“…LABD autoantibodies mainly target either the 120‐kDa (LAD1) and 97‐kDa (LABD97) processed extracellular polypeptides of BP180 (also known as collagen XVII) or collagen VII, and these LABD types are respectively known as lamina densa‐type and sublamina densa‐type LABD . In LABD, the linear deposition of IgG‐class autoantibodies can be observed at the dermoepidermal junction, and such cases have been recently reported as linear IgA/IgG bullous dermatosis (LAGBD) . It remains uncertain whether LAGBD has clinical and immunological characteristics distinct from those of classical LABD.…”

Non‐paraneoplastic autoimmune subepidermal bullous disease associated with fatal bronchiolitis obliterans

“…As the mucous membranes were not affected in our patient, the diagnosis of mucous membrane pemphigoid could not be made for our case, either. It is notable that some cases of linear IgA/IgG bullous dermatosis showed IgA and/or IgG reactivity to various subunits of laminin‐332 …”

“…Immunoblot analyses were performed as described previously . Although the patient's serum contained IgG and IgA antibodies to the epidermal side of the BMZ (Fig.…”

Linear immunoglobulin A/immunoglobulin G bullous dermatosis with autoantibodies to LAD-1 and laminin-γ1

“…To our knowledge, only seven patients with LAGBD with multiple autoantibodies have been reported previously (Table ) . Most of these cases showed reactivity with laminin‐332 and/or BP180.…”

“…Linear immunoglobulin (Ig)A/IgG bullous dermatosis (LAGBD) is characterized by linear depositions of IgA and IgG in the basement membrane zone . LAGBD has been reported to react with heterogeneous antigens such as linear IgA dermatosis antigen (LAD)‐1, linear IgA bullous dermatosis (LABD) antigen (97 kDa), bullous pemphigoid (BP)180, BP230, type VII collagen and laminin‐332 . In addition, LAGBD may rarely have multiple reactions with these antigens .…”