Ligocki Ann J, Rivas Jacqueline R, Rounds William H, Guzman Alyssa A, Li Min, Spadaro Melania, Lahey Lauren, Chen Ding, Henson Paul M, Graves Donna, Greenberg Benjamin M, Frohman Elliot M, Ward E Sally, Robinson William, Meinl Edgar, White Charles L, Stowe Ann M, Monson Nancy L
Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
Institute of Clinical Neuroimmunology, Ludwig-Maximilian-University, Munich, Germany.
ASN Neuro. 2015 Oct 21;7(5). doi: 10.1177/1759091415609613. Print 2015 Sep-Oct.
*These authors contributed equally to the work in this manuscript.We have previously identified a distinct class of antibodies expressed by B cells in the cerebrospinal fluid (CSF) of early and established relapsing remitting multiple sclerosis (RRMS) patients that is not observed in healthy donors. These antibodies contain a unique pattern of mutations in six codons along VH4 antibody genes that we termed the antibody gene signature (AGS). In fact, patients who have such B cells in their CSF are identified as either having RRMS or developing RRMS in the future. As mutations in antibody genes increase antibody affinity for particular antigens, the goal for this study was to investigate whether AGS(+) antibodies bind to brain tissue antigens. Single B cells were isolated from the CSF of 10 patients with early or established RRMS. We chose 32 of these B cells that expressed antibodies enriched for the AGS for further study. We generated monoclonal full-length recombinant human antibodies (rhAbs) and used both immunological assays and immunohistochemistry to investigate the capacity of these AGS(+) rhAbs to bind brain tissue antigens. AGS(+) rhAbs did not recognize myelin tracts in the corpus callosum. Instead, AGS(+) rhAbs recognized neuronal nuclei and/or astrocytes, which are prevalent in the cortical gray matter. This pattern was unique to the AGS(+) antibodies from early and established RRMS patients, as AGS(+) antibodies from an early neuromyelitis optica patient did not display the same reactivity. Prevalence of CSF-derived B cells expressing AGS(+) antibodies that bind to these cell types may be an indicator of gray matter-directed autoimmunity in early and established RRMS patients.
这些作者对本手稿中的工作贡献相同。我们之前在早期和确诊的复发缓解型多发性硬化症（RRMS）患者的脑脊液（CSF）中发现了一类独特的B细胞表达的抗体，而在健康供体中未观察到此类抗体。这些抗体在VH4抗体基因的六个密码子中含有独特的突变模式，我们将其称为抗体基因特征（AGS）。事实上，脑脊液中存在此类B细胞的患者被确定为患有RRMS或未来会发展为RRMS。由于抗体基因中的突变会增加抗体对特定抗原的亲和力，本研究的目的是调查AGS（+）抗体是否与脑组织抗原结合。从10例早期或确诊的RRMS患者的脑脊液中分离出单个B细胞。我们从这些B细胞中选择了32个表达富含AGS抗体的B细胞进行进一步研究。我们生成了单克隆全长重组人抗体（rhAbs），并使用免疫测定和免疫组织化学方法来研究这些AGS（+）rhAbs与脑组织抗原结合的能力。AGS（+）rhAbs未识别胼胝体中的髓鞘束。相反，AGS（+）rhAbs识别神经元细胞核和/或星形胶质细胞，这些细胞在皮质灰质中普遍存在。这种模式是早期和确诊的RRMS患者的AGS（+）抗体所特有的，因为早期视神经脊髓炎患者的AGS（+）抗体没有表现出相同的反应性。表达与这些细胞类型结合的AGS（+）抗体的脑脊液来源的B细胞的患病率可能是早期和确诊的RRMS患者灰质定向自身免疫的一个指标。
