Crinum Latifolium Leave Extracts Suppress Immune Activation Cascades in Peripheral Blood … 331 was measured by reduction of the tetrazole 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl- tetrazolium bromide (MTT) (Sigma Aldrich, Vienna, Austria), which is reduced to purple formazan in living cells, and by trypan blue exclusion method in three experiments done in triplicate. No toxicity of the Crinum latifolium extract could be observed in PBMC at the concentration range applied [0.1–2.5 mg/ml]. After incubation of PC3-, BPH-1- or LNCaP- cells with increasing concentrations of Crinum latifolium extract [0.25–5 mg/ml] or cisplatin [0.1–10 nM] for 72 hours, cell viability was measured with Cell Titer Blue reagent (Promega, Mannheim, Germany), which measures metabolic activity of living cells by reduction of resazurin to resofurin. These experiments were performed in three independent experiments done in duplicates. Statistical analysis For statistical analysis, the Statistical Package for the Social Sciences (version 14 SPSS, Chicago, Ill, USA) was used. Because not all data sets showed normal distribution, for comparison of grouped data non-parametric Friedman test and Wilcoxon signed ranks test were applied. P-values below 0.05 were considered to indicate significant differences. Acknowledgement The authors thank Miss Maria Gleinser for excellent technical assistance. Authors’ Statements Competing Interests The authors declare no conflict of interest. Informed Consent PBMC were isolated from whole blood obtained from healthy donors, of whom informed consent was obtained that their donated blood unit was used for scientific purposes if not otherwise used. References [1] [2] [3] [4] Fennell CW, van Staden J. Crinum species in traditional and modern medicine. Ethnopharmacol. 2001; 78: 15–26. doi:10.1016/S0378-8741(01)00305-1 Tram NTN, Titorenkova TV, St Bankova V, Handjieva NV, Popov SS. Crinum L. (Amaryllidaceae). Fitoterapia. 2002; 73: 183–208. doi:10.1016/S0367-326X(02)00068-0 Beckstrom-Sternberg SM, Duke JA, Wain KK. The ethnobotany database. Genome Informatics Group, National Agricultural Library. U.S. Department of Agriculture, Beltsville, MD, 1994. Usher G. A Dictionary of Plants Used by Man. Constable and Company Ltd., London, 1974. Sci Pharm. 2011; 79: 323–335