使用激光扫描共聚焦显微镜进行荧光叠层抗原定位，可将由 IgA 介导的线性 IgA 大疱性皮病与获得性大疱性表皮松解症区分开来。

Fluorescence overlay antigen mapping using laser scanning confocal microscopy differentiates linear IgA bullous dermatosis from epidermolysis bullosa acquisita mediated by IgA.

机构信息

Department of Dermatology, Medical University of Warsaw, Koszykowa 82a str., 02-008 Warsaw, Poland.

出版信息

Br J Dermatol. 2013 Mar;168(3):634-8. doi: 10.1111/bjd.12017.

DOI:10.1111/bjd.12017

PMID:22924407

Abstract

BACKGROUND

Linear IgA bullous dermatosis (LABD) and epidermolysis bullosa acquisita (EBA) mediated by IgA antibodies belong to the group of autoimmune subepidermal bullous diseases mediated by IgA autoantibodies. Early and correct diagnosis is crucial because the management and prognosis of the diseases are different.

OBJECTIVES

To determine whether fluorescence overlay antigen mapping using laser scanning confocal microscopy (FOAM-LSCM) is helpful in the differentiation between these diseases.

METHODS

FOAM-LSCM and immunoblot studies were performed in 19 patients with disseminated tense blisters who presented with in vivo bound and circulating IgA antibasement membrane zone (BMZ) antibodies on immunofluorescence.

RESULTS

Using FOAM-LSCM, in vivo bound IgA above type IV collagen, which is characteristic for LABD, was seen in 14 of the 19 cases, whereas five of the 19 cases had IgA deposits below type IV collagen, typical for EBA. Immunoblot studies showed that IgA antibodies in 11 of the 14 patients with deposits above type IV collagen reacted with different epitopes on BP180, mainly with LAD-1, which is a target antigen in LABD. Among the five patients with deposits below type IV collagen, one showed IgA antibodies to the 200-kDa laminin γ-1 and one had antibodies to the 290-kDa type VII collagen, EBA antigen. Additionally, enzyme-linked immunosorbent assay with recombinant type VII collagen was positive in three of the five cases who presented with IgA deposits below type IV collagen on FOAM-LSCM.

CONCLUSIONS

The results using FOAM-LSCM were consistent with those obtained on immunoblotting. FOAM-LSCM is useful in routine diagnostics in cases with undetectable circulating anti-BMZ antibodies, and can differentiate LABD from IgA-EBA, the former with in vivo bound IgA above type IV collagen and the latter with IgA deposits below type IV collagen.

摘要

背景

由 IgA 抗体介导的线性 IgA 大疱性皮病（LABD）和获得性大疱性表皮松解症（EBA）属于 IgA 自身抗体介导的自身免疫性表皮下大疱病。早期和正确的诊断至关重要，因为这些疾病的治疗和预后不同。

目的

确定使用激光扫描共聚焦显微镜（LSCM）进行荧光重叠抗原定位（FOAM-LSCM）是否有助于区分这些疾病。

方法

对 19 例弥漫性紧张水疱患者进行 FOAM-LSCM 和免疫印迹研究，这些患者在免疫荧光中表现为体内结合和循环 IgA 抗基底膜带（BMZ）抗体。

结果

使用 FOAM-LSCM，在 19 例病例中，14 例可见 IV 型胶原上方的体内结合 IgA，这是 LABD 的特征，而 19 例中有 5 例 IV 型胶原下方有 IgA 沉积，这是 EBA 的特征。免疫印迹研究显示，在 14 例沉积在上层 IV 型胶原的患者中，IgA 抗体与 BP180 上的不同表位反应，主要与 LABD 的靶抗原 LAD-1 反应。在 5 例 IV 型胶原下沉积的患者中，1 例对 200kDa 层粘连蛋白 γ-1 有 IgA 抗体，1 例对 290kDa 型 VII 胶原，EBA 抗原有抗体。此外，在 FOAM-LSCM 上表现为 IV 型胶原下 IgA 沉积的 5 例患者中，3 例酶联免疫吸附试验（ELISA）用重组型 VII 胶原呈阳性。