Department of Dermatology and Cutaneous Biology Research Institute, Yonsei University College of Medicine, Seoul, Korea.
Br J Dermatol. 2013 May;168(5):977-83. doi: 10.1111/bjd.12128.
Infectious agents, especially Streptococcus sanguinis and herpes simplex virus, have long been postulated as major triggering factors for Behçet disease (BD).
To identify an anti-S. sanguinis antigen reacting with serum IgA antibody in patients with BD.
We detected a target protein by proteomics analysis and evaluated serum IgA reactivity of 100 patients with BD against the identified streptococcal target protein and human heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1. Homologous epitope sequences between the streptococcal target protein and human hnRNP A2/B1 were also evaluated.
Four protein bands were detected by immunoprecipitation, and chaperonin GroEL was identified by a proteomics analysis. Reactivity of serum IgA against recombinant S. sanguinis GroEL was detected in 77 of 100 patients with BD (77%) and in 21 of 70 healthy controls (30%). In addition, reactivity of serum IgA against human recombinant hnRNP A2/B1 was seen in 79 of 100 patients with BD (79%) and in eight of 70 healthy controls (11%). Among the eight distinctive epitopes with significant homology between S. sanguinis GroEL and human hnRNP A2/B1, the serum IgA reactivity of patients with BD was markedly higher with epitope 3 (hnRNP A2/B1 peptide 33-46 and GroEL peptide 57-70) and epitope 6 (hnRNP A2/B1 peptide 177-188 and GroEL peptide 347-358).
We identified an S. sanguinis GroEL protein as a target of serum anti-S. sanguinis IgA antibody reactivity in patients with BD. In addition, patients with BD exhibited serum IgA reactivity against homologous epitope regions between S. sanguinis GroEL and human hnRNP A2/B1.
感染因子，尤其是酿脓链球菌和单纯疱疹病毒，长期以来一直被认为是贝赫切特病（BD）的主要触发因素。
鉴定与 BD 患者血清 IgA 抗体反应的抗酿脓链球菌抗原。
我们通过蛋白质组学分析检测靶蛋白，并评估 100 例 BD 患者血清针对鉴定出的链球菌靶蛋白和人异质核核糖核蛋白（hnRNP）A2/B1 的 IgA 反应性。还评估了链球菌靶蛋白和人 hnRNP A2/B1 之间同源表位序列。
通过免疫沉淀检测到 4 条蛋白带，通过蛋白质组学分析鉴定出伴侣蛋白 GroEL。在 100 例 BD 患者中有 77%（77/100）和 70 例健康对照者中有 30%（21/70）检测到针对重组酿脓链球菌 GroEL 的血清 IgA 反应性。此外，在 100 例 BD 患者中有 79%（79/100）和 70 例健康对照者中有 11%（8/70）检测到针对人重组 hnRNP A2/B1 的血清 IgA 反应性。在酿脓链球菌 GroEL 与人类 hnRNP A2/B1 之间具有显著同源性的 8 个独特表位中，BD 患者的血清 IgA 反应性与表位 3（hnRNP A2/B1 肽 33-46 和 GroEL 肽 57-70）和表位 6（hnRNP A2/B1 肽 177-188 和 GroEL 肽 347-358）明显更高。
我们鉴定出酿脓链球菌 GroEL 蛋白是 BD 患者血清抗酿脓链球菌 IgA 抗体反应的靶蛋白。此外，BD 患者表现出针对酿脓链球菌 GroEL 和人 hnRNP A2/B1 之间同源表位区域的血清 IgA 反应性。
