The A and the extended V N-terminal regions of streptococcal protein I/IIf mediate the production of tumour necrosis factor α in the monocyte cell line THP-1
The A and the extended V N-terminal regions of streptococcal protein I/IIf mediate the production of tumour necrosis factor α in the monocyte cell line THP-1
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DOI：
10.1046/j.1365-2958.1998.00881.x
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发表时间：
1998-07-01
影响因子：
3.6
通讯作者：
Klein, JP
中科院分区：
文献类型：
--
作者：
Chatenay-Rivauday, C;Yamodo, I;Klein, JP
通过使用含有蛋白质的离散结构域的重组多肽，研究了由来自变形链球菌血清型f的链球菌抗原I/II（蛋白质I/IIf）诱导来自单核细胞系THP-1的肿瘤坏死因子（TNF）-α。携带的N-末端丙氨酸丰富的区域（A区）和相邻的可变区（扩展的V区）的蛋白质结合THP-1细胞提取物中的饱和的方式，和一个衍生物缺乏的A和扩展的V区不能结合单核细胞提取物，这表明负责蛋白质I/IIf的结合单核细胞的结构域的A和扩展的V区。THP-1细胞提取物的偏高碘酸钠预处理、单核细胞的衣霉素预处理或与N-乙酰神经氨酸（NANA）和岩藻糖的竞争导致携带扩展V区的衍生物的结合活性降低45-70%，表明扩展V区识别单核细胞受体的凝集素样模式以及NANA和岩藻糖在此识别过程中的作用。此外，含有A区和延伸的V区的衍生物刺激单核细胞释放TNF-α是有效的，并且不受添加多粘菌素B或维生素D-3的影响，表明CD 14在蛋白I/IIf刺激单核细胞释放TNF-α中不起受体作用。
The induction of tumour necrosis factor (TNF)-alpha from the monocytic cell line THP-1 by the streptococcal antigen I/II from Streptococcus mutans serotype f (protein I/IIf) was studied by use of recombinant polypeptides containing discrete domains of the protein. The derivatives carrying the N-terminal alanine-rich region (A region) and the adjacent variable region (extended V region) of the protein bound to THP-1 cell extracts in a saturable fashion, and one derivative lacking both the A and the extended V regions was not able to bind monocyte cell extracts, suggesting that the domains responsible for the binding of protein I/IIf to monocytes were the A and the extended V regions. Sodium metaperiodate pretreatment of THP-1 cell extracts, tunicamycin pretreatment of monocyte cells or competition with N-acetyl neuraminic acid (NANA) and fucose resulted in a 45-70% reduction in binding activity of the derivatives carrying the extended V region, demonstrating the lectin-like mode of recognition of the monocytic receptor by the extended V region and the role of NANA and fucose in this recognition process. Besides, the stimulation of monocytes to release TNF-alpha by the derivatives containing the A region and the extended V region was effective and was not affected by the addition of polymyxin B or vitamin D-3, suggesting that CD14 does not play the role of receptor in stimulation of monocytes by protein I/IIf to release TNF-alpha.