Antigen recognition in the pathogenesis of immunoglobulin A-related autoimmune bullous diseases

Abstract

Immunoglobulin A (IgA) is the most common subtype of antibodies in mucosal surfaces. In most of autoimmune bullous diseases, however, immunoglobulin G (IgG) is the main pathogenic antibody that plays a role through complementation. The IgA antibody for epidermal connection protein can be found in the sera of some patients with blistering skin disease. Of these patients, some have the IgA antibody in their sera, while others have IgG and IgA antibodies. IgA-related autoimmune bullous diseases are less common in clinical practice. In the past, these diseases were not fully understood and their classifications were confusing. Recently, some progress has been made in the study of these diseases.

IgA autoantibody may be the foremost pathogenic in three cases of linear IgA/IgG bullous dermatosis

“…However, many patients exhibit atypical clinical manifestations and thus their conditions are difficult to categorize into BP or LABD. 6 We diagnosed these three cases as LAGBD by histopathological and immunological results. The three patients showed subepidermal blisters with predominantly neutrophilic infiltrates.…”

“…Their studies also showed the sensitivity of ELISAs for IgA and IgG antibodies in LABD was lower than ss‐IIF. Similar to LABD, LAGBD has been reported to have IgA and IgG binding mostly to the epidermal surface and rarely combined epidermal‐dermal or dermal sites 4–8 …”

Immunologic overlap in a case of linear IgG/IgA bullous dermatosis responsive to rituximab

“…The relationship between LAGBD clinical manifestations and the type of predominant antibody highlights that BP, LAGBD, and LABD are on a spectrum. 20 …”

“…The relationship between LAGBD clinical manifestations and the type of predominant antibody highlights that BP, LAGBD, and LABD are on a spectrum. 20 Histopathologic evaluation shows subepidermal bullae. 1 Eosinophilic spongiosis and/or dermal infiltrate of eosinophils are seen in BP.…”

Review of an Anti-CD20 Monoclonal Antibody for the Treatment of Autoimmune Diseases of the Skin

“…Both LABD and LAGBD are blistering diseases caused by deposition of autoantibodies targeting integral components of BMZ, similar to BP. BP, LAGBD, and LABD are believed to be on a spectrum, and for LAGBD, the clinical presentation and pathological findings are determined by predominance of either IgG or IgA deposited along the BMZ [ 55 ]. In LABD, the IgA autoantibodies are formed against the 97 kDa or 120 kDa fractions of BP180, and sometimes collagen VII (COL7) [ 36 ].…”