Investigation of the KIR4.1 potassium channel as a putative antigen in patients with multiple sclerosis: a comparative study.
Investigation of the KIR4.1 potassium channel as a putative antigen in patients with multiple sclerosis: a comparative study.
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DOI：
10.1016/s1474-4422(14)70141-3
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发表时间：
2014-08
期刊：
影响因子：
48
通讯作者：
Lennon, Vanda A.
中科院分区：
文献类型：
--
作者：
Brickshawana, Adipong;Hinson, Shannon R.;Romero, Michael F.;Lucchinetti, Claudia F.;Guo, Yong;Buttmann, Mathias;McKeon, Andrew;Pittock, Sean J.;Chang, Min-Hwang;Chen, An-Ping;Kryzer, Thomas J.;Fryer, James P.;Jenkins, Sarah M.;Cabre, Philippe;Lennon, Vanda A.
多发性硬化症(MS)的免疫球蛋白产生、免疫球蛋白和补体沉积在最常见的免疫病理损害亚型(模式II)中，以及最近的一项报告表明，多发性硬化症(MS)患者中有47%的血清含有胶质细胞potassium-channel-specific-IgG(inwardly-rectifying，，提示多发性硬化症(MS)具有抗体依赖性致病作用。本研究的目的是确定多发性硬化症患者血清和脑脊液中Kir4.1结合免疫球蛋白的频率和特异性，以及在脱髓鞘的MS病变中，Kir4.1免疫反应性是保留还是丧失。我们用酶联免疫吸附试验检测了286例临床和地理分布不同的MS患者(229例人群和57例临床病例)、99例健康对照和109例疾病对照的血清和25例MS和22例对照的脑脊液。CSF和基于临床的MS亚群血清(50)在表达Kir4.1的功能性细胞上进行测试，使用经验证的检测临床相关神经质膜反应性自身抗体的方法：免疫荧光法和免疫沉淀法(溶解的重组人Kir4.1)。我们对15例经组织病理证实的MS患者(22个斑块：8个早期活动斑块，8个非活动斑块，6个再生髓鞘斑块，13个斑块周围区域)和3个非神经系统病例(8个正常外观的白质/灰质区)进行了脑内Kir4.1免疫反应的检测。KIR4.1-多肽-ELISA法反应罕见，与286例MS或208例对照血清(均为1%)的反应性无显著差异；无一例脑脊液呈阳性。IgGin 0/50临床MS患者血清免疫沉淀Kir4.1，而对照Kir4.1特异性-Ig G免疫沉淀。免疫荧光显示，1/50的MS血清在Kir4.1表达和不表达的细胞上均有微弱的胞浆染色，16/50的MS血清与细胞内成分有微弱的结合。在所有情况下，用肝粉或未转染的细胞裂解物吸收可使免疫球蛋白结合消失。对照的Kir4.1-特异性结合只被Kir4.1蛋白裂解物淬灭。0/25MS CSF中的免疫球蛋白与Kir4.1转基因细胞结合，活的或固定的。在早期活动性和有髓鞘的MS病变以及斑块周围白质(15名患者)中，相对于基线正常脑表达(3名对照)，胶质细胞Kir4.1免疫反应增强。在MS血清或脑脊液中未发现Kir4.1特异性抗体，在活动期脱髓鞘MS病变的胶质细胞中也未发现Kir4.1的丢失。Kir4.1-Ig G的血清学检测不太可能有助于MS的诊断。多发性硬化症的靶抗原仍然难以捉摸。国立卫生研究院、国家多发性硬化症协会和梅奥诊所罗伯特和阿琳·科戈德老龄中心。
Antibody-dependent pathogenicity is suggested in multiple sclerosis (MS) by intrathecal immunoglobulin production, IgG and complement deposition in the most common immunopathological lesion subtype (pattern II), and by a recent report that 47% of MS patients’ sera contain a glial potassium-channel-specific-IgG(inwardly-rectifying, Kir4.1). Our study’s aims were to determine, in MS serum and CSF, the frequency and specificity of Kir4.1-binding-IgG and, in demyelinating MS lesions, whether Kir4.1-immunoreactivity is retained or lost. We tested by ELISA(Kir4.1-peptide 83–120) sera from 286 clinically and geographically diverse MS patients (229 population-based and 57 clinic-based),99 healthy controls and 109 disease controls, and cerebrospinal fluid [CSF] from 25 MS and 22 controls. CSFs and clinic-based MS-subset serum (50)were tested on functional Kir4.1-expressing cells, using methodologies validated for detecting clinically-pertinent neural plasma membrane-reactive autoantibodies: immunofluorescence and immunoprecipitation (solubilized recombinant human Kir4.1). We evaluated Kir4.1-immunoreactivity in brain from 15 archival histopathologically-confirmed MS cases(22 plaques: 8 early active, 8 inactive, 6 remyelinated; 13 periplaque regions)and compared 3 non-neurological cases (8 normal-appearing white/gray matter regions). Kir4.1-peptide-ELISA reactivity was rare and did not differ significantly for 286 MS or 208 control sera (both 1%); no CSF was positive. IgGin 0/50 clinic-based MS sera immunoprecipitated Kir4.1, but control Kir4.1-specific-IgG did. By immunofluorescence,1/50 MS sera yielded faint plasmalemmal staining on both Kir4.1-expressing and non-expressing cells; 16/50 bound faintly to intracellular components. In all cases, IgG binding was quenched by absorption with liver powder or non-transfected cell lysates. Control Kir4.1-specific-IgG binding was quenched only by Kir4.1 protein-containing lysates. IgG in 0/25 MS CSFs bound to Kir4.1-transfected cells, live or fixed. Glial Kir4.1-immunoreactivity was increased relative to baseline normal brain expression (3 controls) in early active and remyelinated MS lesions, and in periplaque white matter (15 patients). We did not find Kir4.1-specific-IgG in MS sera or CSF, nor Kir4.1 loss from glial cells in active demyelinating MS lesions. Serological testing for Kir4.1-IgG is unlikely to aid MS diagnosis. The target antigen of MS remains elusive. The National Institutes of Health, the National Multiple Sclerosis Society and the Mayo Clinic Robert and Arlene Kogod Center on Aging.