Analyse des signes cliniques des malades atteints de pemphigoïde en fonction des antigènes reconnus par leur sérum en immunotransfert

Deciphering the Contribution of BP230 Autoantibodies in Bullous Pemphigoid

Bullous pemphigoid (BP) is a subepidermal autoimmune blistering disease predominantly affecting elderly patients and carries significant morbidity and mortality. Patients typically suffer from severe itch with eczematous lesions, urticarial plaques, and/or tense blisters. BP is characterized by the presence of circulating autoantibodies against two components of the hemidesmosome, BP180 and BP230. The transmembrane BP180, also known as type XVII collagen or BPAG2, represents the primary pathogenic autoantigen in BP, whereas the intracellular BP230 autoantigen is thought to play a minor role in disease pathogenesis. Although experimental data exist suggesting that anti-BP230 antibodies are secondarily formed following initial tissue damage mediated by antibodies targeting extracellular antigenic regions of BP180, there is emerging evidence that anti-BP230 IgG autoantibodies alone directly contribute to tissue damage. It has been further claimed that a subset of patients has a milder variant of BP driven solely by anti-BP230 autoantibodies. Furthermore, the presence of anti-BP230 autoantibodies might correlate with distinct clinical features. This review summarizes the current understanding of the role of BP230 and anti-BP230 antibodies in BP pathogenesis.

BP180- and BP230-specific IgG autoantibodies in pruritic disorders of the elderly: a preclinical stage of bullous pemphigoid?

Pruritus increasingly occurs in the elderly population and is associated with a variety of dermatoses of mixed aetiology. Clinical and experimental evidence suggests that senile pruritus may be linked to autoimmune events initiated by loss of self-tolerance against cutaneous autoantigens, which is facilitated by immune ageing processes. T-cell immunity, which underpins the production of pathogenic autoantibodies in autoimmune diseases, is deregulated by immune senescence thereby leading to autoimmune disorders such as bullous pemphigoid (BP). High mortality rates of BP combined with steadily increasing incidence emphasize the need for an effective diagnostic strategy at an early stage. We summarize here the current understanding of immunological alterations during the ageing process, thereby focusing on aberrant T-cell responses against the basement membrane antigens BP180 and BP230, which may eventually lead to the clinical outcome of BP.