Division of Allergy, Immunology and Rheumatology, Department of Medicine, University of Rochester Medical Center, Rochester, NY 14642.
J Immunol. 2014 Apr 1;192(7):3011-20. doi: 10.4049/jimmunol.1302003. Epub 2014 Feb 26.
Autoantibodies to dsDNA, produced by autoreactive plasma cells (PCs), are a hallmark of systemic lupus erythematosus and play a key role in disease pathogenesis. Recent data suggest that autoreactive PCs accumulate not only in lymphoid tissues, but also in the inflamed kidney in lupus nephritis. We hypothesized that the variable efficacy of anti-CD20 (rituximab)-mediated B cell depletion in systemic lupus erythematosus may be related to the absence of an effect on autoreactive PCs in the kidney. In this article, we report that an enrichment of autoreactive dsDNA Ab-secreting cells (ASCs) in the kidney of lupus-prone mice (up to 40% of the ASCs) coincided with a progressive increase in splenic germinal centers and PCs, and an increase in renal expression for PC survival factors (BAFF, a proliferation-inducing ligand, and IL-6) and PC attracting chemokines (CXCL12). Short-term treatment with anti-CD20 (4 wk) neither decreased anti-dsDNA nor IgG ASCs in different anatomical locations. However, long-term treatment (12 wk) significantly reduced both IgG- and dsDNA-specific ASCs. In addition, long-term treatment substantially decreased splenic germinal center and PC generation, and unexpectedly reduced the expression for PC survival factors in the kidney. These results suggest that prolonged B cell depletion may alter the PC survival niche in the kidney, regulating the accumulation and maintenance of autoreactive PCs.
针对双链 DNA(dsDNA)的自身抗体由自身反应性浆细胞(PC)产生,是红斑狼疮的标志性特征,在疾病发病机制中起关键作用。最近的数据表明,自身反应性 PC 不仅在淋巴组织中积累,而且在狼疮性肾炎的炎症肾脏中积累。我们假设抗 CD20(利妥昔单抗)介导的 B 细胞耗竭在系统性红斑狼疮中的疗效差异可能与它对肾脏中自身反应性 PC 没有作用有关。在本文中,我们报告说,狼疮易感小鼠肾脏中自身反应性 dsDNA Ab 分泌细胞(ASC)的富集(高达 ASC 的 40%)与脾脏生发中心和 PC 的逐渐增加以及 PC 存活因子(BAFF、增殖诱导配体和 IL-6)和 PC 吸引趋化因子(CXCL12)在肾脏中的表达增加同时发生。短期抗 CD20(4 周)治疗既不能减少不同解剖部位的抗 dsDNA 也不能减少 IgG ASC。然而,长期治疗(12 周)显著减少了 IgG 和 dsDNA 特异性 ASC。此外,长期治疗还显著减少了脾脏生发中心和 PC 的生成,并出人意料地减少了肾脏中 PC 存活因子的表达。这些结果表明,延长 B 细胞耗竭可能会改变肾脏中 PC 的生存环境,从而调节自身反应性 PC 的积累和维持。