Key Laboratory of Tropical Diseases and Control, Ministry of Education, Guangzhou, China.
Parasitol Res. 2014 Aug;113(8):3073-83. doi: 10.1007/s00436-014-3973-y. Epub 2014 Jun 7.
Sj16, a 16-kDa protein secreted from Schistosoma japonicum, has been demonstrated an anti-inflammatory effect in vitro and in vivo, but its mechanism is still not clear. In this study, microarray analysis was performed to investigate the effects of recombinant Sj16 (rSj16) on the gene expression of the lipopolysaccharide (LPS)-stimulated dendritic cells (DCs). Immature DCs were treated with LPS, LPS + recombinant Sj16 (rSj16), or rSj16 alone for 24 h, and the gene expression profiles were examined using complementary DNA (cDNA) microarrays. With the cutoff value of 2-fold change in the expression, 509 genes were affected, 226 genes upregulated, and 283 genes downregulated after adding rSj16. Analysis by functional annotation clustering tool showed that rSj16-affected genes mainly associated with inflammatory response, defense response, regulation of immune system process, apoptosis, and cell migration. The results revealed that rSj16 reduced the LPS-induced pro-inflammatory genes such as cytokines (e.g., IL6, IL18, IFN-γ, IL12a, IL1b), chemokines, and receptors (e.g., CXCL1, CXCL9, CCL5, CCR5, CCR1, CCR2, CXCR3) and increased the anti-inflammatory gene IL-10. Further data mining of these genes by pathway analysis showed that genes regulated by rSj16 were significantly involved in cytokine-cytokine receptor interaction, NOD-like receptor signaling pathway, Toll-like receptor signaling pathway, antigen processing and presentation, and Jak-STAT signaling pathway. In addition, quantitative real-time PCR (qRT-PCR) and Western blot analysis showed that rSj16 downregulated the expression of inhibitor of nuclear factor kappa-β kinase subunit beta (IKKβ) and nuclear factor-kappa β p65 (NF-κβ) messenger RNA (mRNA) and inhibited the phosphorylation of IKKβ and the NF-κB p65 protein, which implied that rSj16 exerting immunomodulatory effects by suppressing NF-κB signaling pathway. These results provide useful information in further understanding of the immunoregulation mechanisms of Sj16, and it is indicated that Sj16 could be as a potential molecule for the immunosuppressant drug development.
日本血吸虫 16kDa 蛋白（Sj16）在体内外均表现出抗炎作用，但作用机制尚不清楚。本研究采用基因芯片技术分析重组 Sj16（rSj16）对脂多糖（LPS）刺激的树突状细胞（DC）基因表达的影响。用 LPS、LPS+rSj16 或 rSj16 单独处理未成熟 DC 24 h，采用 cDNA 芯片检测基因表达谱。以表达水平变化 2 倍为界值，rSj16 作用后有 509 个基因发生变化，其中 226 个基因上调，283 个基因下调。功能注释聚类分析表明，rSj16 作用后的基因主要与炎症反应、防御反应、免疫系统过程的调节、细胞凋亡和细胞迁移有关。结果显示 rSj16 可下调 LPS 诱导的促炎细胞因子（如 IL6、IL18、IFN-γ、IL12a、IL1b）、趋化因子和受体（如 CXCL1、CXCL9、CCL5、CCR5、CCR1、CCR2、CXCR3），上调抗炎细胞因子 IL-10。进一步对这些基因进行通路分析发现，rSj16 调节的基因显著参与细胞因子-细胞因子受体相互作用、NOD 样受体信号通路、Toll 样受体信号通路、抗原加工和呈递以及 Jak-STAT 信号通路。此外，实时定量 PCR（qRT-PCR）和 Western blot 分析显示 rSj16 下调核因子-κB 激酶亚单位β（IKKβ）和核因子-κB p65（NF-κβ）信使 RNA（mRNA）的表达，并抑制 IKKβ 和 NF-κB p65 蛋白的磷酸化，提示 rSj16 通过抑制 NF-κB 信号通路发挥免疫调节作用。这些结果为进一步了解 Sj16 的免疫调节机制提供了有用的信息，并表明 Sj16 可能成为免疫抑制剂药物开发的潜在分子。
