Vimentin Is a Dominant Target of In Situ Humoral Immunity in Human Lupus Tubulointerstitial Nephritis
Vimentin Is a Dominant Target of In Situ Humoral Immunity in Human Lupus Tubulointerstitial Nephritis
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DOI：
10.1002/art.38888
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发表时间：
2014-12-01
影响因子：
13.3
通讯作者：
Clark, Marcus R.
中科院分区：
文献类型：
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作者：
Kinloch, Andrew J.;Chang, Anthony;Clark, Marcus R.
客观的。在狼疮性肾炎 (LN) 中，严重的肾小管间质炎症 (TII) 预示着进展为肾衰竭。严重的 TII 与三级淋巴新生和原位抗原驱动的克隆 B 细胞选择有关。 TII 中驱动原位 B 细胞选择的自身抗原尚不清楚。这项研究的目的是确定主要的驱动自身抗原。方法。从诊断 LN 的 7 个活检标本中激光捕获单个 CD38 或 Ki-67 B 细胞。克隆了十八个克隆扩展的免疫球蛋白重链和轻链可变区对并表达为单克隆抗体。从第八个活检样本的流式分选 CD38 细胞中克隆了另外七种抗体。结合使用共聚焦显微镜、酶联免疫吸附测定、筛选原型阵列、免疫沉淀和质谱来进行抗原表征。使用纯化的抗原包被阵列测定了 48 个 LN 和 35 个非肾炎狼疮样本中针对主要抗原的血清 IgG 滴度。通过免疫组织化学和免疫荧光定位正常肾和淋巴结肾上的自身抗原表达。结果。 25 种抗体中有 11 种与细胞质结构反应，4 种与细胞核反应，没有一种与双链 DNA 反应。波形蛋白是唯一通过质谱和原型阵列鉴定的自身抗原。 11 种抗细胞质 TII 抗体中有 10 种直接结合波形蛋白。波形蛋白在肾小管间质炎症细胞中高度表达，并且测试的 TII 抗体优先结合发炎的肾小管间质。最后，高滴度的血清抗波形蛋白抗体与严重的 TII 相关（P < 0.0001）。结论。波形蛋白是炎症的一种抗原特征，是 LN TII 中原位靶向的主要自身抗原。这种适应性自身免疫反应可能会加剧 TII 和肾损伤。
Objective. In lupus nephritis (LN), severe tubulointerstitial inflammation (TII) predicts progression to renal failure. Severe TII is associated with tertiary lymphoid neogenesis and in situ antigen-driven clonal B cell selection. The autoantigen(s) driving in situ B cell selection in TII are not known. This study was undertaken to identify the dominant driving autoantigen(s). Methods. Single CD38 or Ki-67 B cells were laser captured from 7 biopsy specimens that were diagnostic for LN. Eighteen clonally expanded immunoglobulin heavy-and light-chain variable region pairs were cloned and expressed as monoclonal antibodies. Seven more antibodies were cloned from flow-sorted CD38 cells from an eighth biopsy specimen. Antigen characterization was performed using a combination of confocal microscopy, enzyme-linked immunosorbent as-say, screening protoarrays, immunoprecipitation, and mass spectrometry. Serum IgG titers to the dominant antigen in 48 LN and 35 non-nephritic lupus samples were determined using purified antigen-coated arrays. Autoantigen expression on normal and LN kidney was localized by immunohistochemistry and immunofluorescence. Results. Eleven of 25 antibodies reacted with cytoplasmic structures, 4 reacted with nuclei, and none reacted with double-stranded DNA. Vimentin was the only autoantigen identified by both mass spectrometry and protoarray. Ten of the 11 anticytoplasmic TII antibodies directly bound vimentin. Vimentin was highly expressed by tubulointerstitial inflammatory cells, and the TII antibodies tested preferentially bound inflamed tubulointerstitium. Finally, high titers of serum antivimentin antibodies were associated with severe TII (P 0.0001). Conclusion. Vimentin, an antigenic feature of inflammation, is a dominant autoantigen targeted in situ in LN TII. This adaptive autoimmune response likely feeds forward to worsen TII and renal damage.