利奈唑胺与万古霉素对小鼠巨噬细胞RAW264.7吞噬功能的影响

Effect of linezolid versus vancomycin on the phagocytosis of mouse macrophages RAW264.7

目的探讨利奈唑胺和万古霉素对金葡菌肽聚糖(PG)刺激的小鼠巨噬细胞系RAW264.7吞噬功能的影响。方法在激光共聚焦显微镜和荧光显微镜下观察巨噬细胞吞噬荧光微球的过程。将小鼠巨噬细胞系分为3组:对照组、PG组和抗菌药组(低、中、高剂量),用流式细胞仪计算吞噬率和吞噬指数。结果异硫氰酸荧光素(FITC)标记的微球可被吞入巨噬细胞内。与对照组相比,经PG刺激后,小鼠巨噬细胞吞噬功能明显上升(P<0.01)。对比PG组,各剂量利奈唑胺组吞噬能力降低(P<0.05),中、高剂量万古霉素组吞噬能力增高(P<0.05),低剂量万古霉素组吞噬功能无明显变化(P>0.05)。结论亚MIC和治疗浓度的利奈唑胺能抑制金葡菌PG刺激引起的吞噬功能的增高,而治疗浓度的万古霉素能增强其吞噬功能。2种药物对吞噬功能不同影响的临床意义尚待阐明。

Objective To investigate the effects of anti-gram-positive antibiotics linezolid versus vancomycin on the phagocytosis of mouse macrophages RAW264.7 in presence of peptidoglycan. Methods The cellular events of fluorescent microsphere-mac- rophage interaction were analyzed by confocal laser scanning microscopy and fluorescence microscopy. Mouse macrophages were assigned to three groups., control group, peptidoglycan group, and antibiotic groups of low, medium and high concentration. The phagocytosis rate and phagoeytosis index were tested by flow cytometry. Results FITC labeled microspheres could be phagocytosed by macrophages. The phagocytosis in peptidoglycan group increased significantly than that in the control group （P〈0.01）. The phagocytosis in the linezolid group was statistically significant lower than those in the peptidoglycan group （P 〈0.05）. The phagoeytosis in the vancomycin groups of medium and high concentrations increased than those in the peptidogly- can group （P〈0.05）, but not in the low concentration group （P〉0.05）. Conclusions Linezolid at sub-MIC and clinically rele- vant concentrations could inhibit the increased phagocytosis stimulated by Staphylococcus aureus peptidoglycan, while vanco- mycin at clinically relevant concentrations could increase the phagocytosis. The clinical relevance of the different effects of these two antibiotics is to be clarified.