The 97 kDa linear IgA bullous disease antigen is identical to a portion of the extracellular domain of the 180 kDa bullous pemphigoid antigen, BPAg2.
The 97 kDa linear IgA bullous disease antigen is identical to a portion of the extracellular domain of the 180 kDa bullous pemphigoid antigen, BPAg2.
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97 kDa 线性 IgA 大疱性疾病抗原与 180 kDa 大疱性类天疱疮抗原 BPAg2 的部分胞外结构域相同。
DOI：
10.1046/j.1523-1747.1998.00129.x
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
Petersen,MJ
中科院分区：
文献类型：
--
作者：
Zone,JJ;Taylor,TB;Meyer,LJ;Petersen,MJ
部分线性IgA大疱性皮肤病（LABD）患者血清中的IgA自身抗体可识别位于基底膜区透明层的97ákDa抗原（LABD97）。由于LABD自身抗体不能与大疱性类天疱疮自身抗体识别的180和230ákDa蛋白发生反应，因此LABD97被认为是一种单独的透明层蛋白。本研究利用单克隆抗体免疫亲和柱从人表皮提取物中纯化了LABD97，并分析了纯化后LABD97的enterminus的氨基酸序列。这揭示了16个氨基酸序列与先前报道的大疱性类天疱疮（BPAg2）中180ákDa抗原的序列相同。TheNterminus位于BPAg2跨膜结构域羧基端下游41个氨基酸和MCW-1结构域下游11个氨基酸，MCW-1是主要的大疱性类天疱疮表位。纯化后的LABD97用内源性蛋白酶Arg C酶切，用层析法分离，得到多个肽段。其中14个馏分进行了氨基酸测序。肽段的氨基酸序列与BPAg2胞外结构域内的序列相同，共205个氨基酸。大疱性类天疱疮血清识别的主要表位位于该蛋白的非胶原区域，而LABD血清识别的表位位于胶原部分内或邻近胶原部分。我们得出结论，LABD97代表了BPAg2细胞外结构域的一部分，并且IgA自身抗体直接针对胶原结构域内或邻近的表位。
IgA autoantibodies from the sera of some patients with linear IgA bullous dermatosis (LABD) recognize a 97ákDa antigen (LABD97) located in the lamina lucida of the basement membrane zone. As LABD autoantibodies do not react with the 180 and 230ákDa proteins recognized by bullous pemphigoid autoantibodies, LABD97 has been thought to represent a separate lamina lucida protein. In this study, we purified LABD97 from the extract of human epidermis using a monoclonal antibody immunoaffinity column and analyzed the amino acid sequence of theNterminus of purified LABD97. This revealed a 16 amino acid sequence that was identical to a previously reported sequence of the 180ákDa antigen in bullous pemphigoid (BPAg2). TheNterminus was located 41 amino acids downstream from the carboxyl end of the transmembrane domain of BPAg2 and 11 amino acids downstream from the MCW-1 domain, the predominant bullous pemphigoid epitope. Purified LABD97 was subsequently enzymatically digested with endoproteinase Arg C and separated by chromatography, which resulted in multiple peptide fractions. Fourteen of these fractions were subjected to amino acid sequencing. The amino acid sequence of the peptide fractions, totaling 205 amino acids, were identical to sequences contained within the extracellular domain of BPAg2. Whereas the predominant epitope identified with bullous pemphigoid sera is located in the noncollagenous region of this protein, the epitope recognized by LABD sera is either within or adjacent to the collagenous portion. We conclude that LABD97 represents a portion of the extracellular domain of BPAg2 and that the IgA autoantibodies are directed against an epitope within or adjacent to a collagenous domain.