Methodological research for the promoting effect of Dendrobium moniliforme on macrophage phagocytosis based on high-content screening / 药学学报

ABSTRACT

The aim of the present study was to explore a sensitive, stable and reliable method for evaluating the phagocytosis, in which RAW264.7 macrophages engulfed GFP-Escherichia coli was tested by high-content screening technology. The study was conducted to optimize the method in evaluation of traditional Chinese medicine in the promotion of macrophage function. By testing macrophages at different ratio of bacteria to cells (multiplicity of infection, MOI), and at different incubation time, we optimized a high content screening method and the experimental parameters to determine the impact of bacteria in macrophages (fluorescence intensity index = be swallowed bacteria/macrophages). The method was used to determine whether Dendrobium moniliforme (DM) have effects on macrophage phagocytosis. The results show that the index has a positive relationship with MOI values, and the highest index was observed at incubation time of 1.5 h. The optimized conditions was 1×104 cells/well with a MOI of 501 (bacteriacells) with incubation of 1.5 h. Under this condition, the relative standard deviation (RSD) was less than 10% in the precision test. Using the method to detect DM regulating macrophage phagocytosis experiment results showed that in 0.31-2.50 g·L-1 concentration range, DM has a dose-response effect in promoting phagocytosis. We successfully established the method for evaluation of macrophage phagocytosis, and proved the activity of DM in promotion of macrophage phagocytosis.