Nichols F C, Peluso J F, Tempro P J, Garrison S W, Payne J B
Department of Peridontology, University of Connecticut School of Dental Medicine, Farmington 06030.
Infect Immun. 1991 Jan;59(1):398-406. doi: 10.1128/iai.59.1.398-406.1991.
The purpose of this investigation was to examine gamma interferon potentiation of lipopolysaccharide (LPS) responses in human monocytes by using phenol-water-extracted (unfractionated) and highly purified LPS preparations isolated from Bacteroides intermedius and Salmonella typhimurium. Phenol-water-extracted LPS preparations from these bacteria were further purified by chromatography over Sepharose-CL-4B. LPS enrichment in pooled column fractions was assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and quantitation of hydroxy-fatty acid and 2-keto-3-deoxyoctulosonic acid content, protein contamination, and anthrone-reactive material. Monocyte stimulation by LPS, measured as prostaglandin E (PGE) release, was assessed with and without gamma interferon treatment. Cells were either treated simultaneously with gamma interferon and LPS or pretreated with gamma interferon prior to LPS stimulation. PGE release from counterflow-isolated monocytes was quantitated during the 0- to 24-h and 24- to 48-h culture intervals. Contrary to previous results from this laboratory, phenol-water-extracted LPS preparations from B. intermedius and S. typhimurium were similar in their capacities to stimulate PGE release from monocytes. Molecular sieve chromatography was found to remove substantial amounts of high-molecular-weight polysaccharide contaminants only from the B. intermedius LPS but did not significantly alter the potency of either B. intermedius or S. typhimurium LPS. Gamma interferon cotreatment did not potentiate the release of PGE with any of the LPS preparations tested. However, 24-h pretreatment of monocytes with gamma interferon followed by a 24-h exposure to LPS resulted in significant potentiation of PGE release over LPS alone. In addition, B. intermedium preparations were approximately threefold more potent than similarly prepared LPS isolates from S. typhimurium following gamma interferon pretreatment. These results indicate that gamma interferon can selectively potentiate the effects of B. intermedius LPS in human monocyte isolates.
本研究的目的是通过使用从中间拟杆菌和鼠伤寒沙门氏菌中分离出的经酚水提取（未分级）和高度纯化的脂多糖（LPS）制剂，来检测γ干扰素对人单核细胞中LPS反应的增强作用。这些细菌的酚水提取LPS制剂通过Sepharose-CL-4B柱色谱进一步纯化。通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳以及对羟基脂肪酸和2-酮-3-脱氧辛酸含量、蛋白质污染和蒽酮反应性物质的定量分析，评估合并柱级分中LPS的富集情况。以前列腺素E（PGE）释放量来衡量LPS对单核细胞的刺激作用，在有和没有γ干扰素处理的情况下进行评估。细胞要么同时用γ干扰素和LPS处理，要么在LPS刺激前用γ干扰素预处理。在0至24小时和24至48小时的培养间隔期间，对逆流分离的单核细胞释放的PGE进行定量。与该实验室先前的结果相反，中间拟杆菌和鼠伤寒沙门氏菌的酚水提取LPS制剂在刺激单核细胞释放PGE的能力方面相似。发现分子筛色谱仅从中间拟杆菌LPS中去除了大量高分子量多糖污染物，但并未显著改变中间拟杆菌或鼠伤寒沙门氏菌LPS的效力。γ干扰素联合处理并未增强所测试的任何LPS制剂的PGE释放。然而，单核细胞用γ干扰素预处理24小时，然后暴露于LPS 24小时，导致PGE释放比单独使用LPS时有显著增强。此外，在γ干扰素预处理后，中间拟杆菌制剂的效力比鼠伤寒沙门氏菌的类似制备LPS分离物高约三倍。这些结果表明，γ干扰素可以选择性地增强中间拟杆菌LPS对人单核细胞分离物的作用。
