Raji cells

The Daudi and Raji human cell lines, with different sensitivities to fludarabine were measured with optophore-sis over a 3 log range of concentrations the Raji cell line had an EC50 value of 1.1 0.27 pg/mL, whereas the much less-sensitive Daudi line had an EC50 of 11.51 3.2 pg/mL. 

Cell growth of lymphoid human Raji cells Content extractable Fluorid (10- M)... 

Epstein-Barr virus early antigen induction. Methanol extract of the dried leaf, in cell culture at a concentration of 1 pg/mL, was inactive. The assay was designed for tumor-promoting activity . Two diastere-oisomers of 2,7,1 l-cembratriene-4,6-diol (a- and 3-CBT) from the neutral fractions of cigarette smoke condensate, in Raji cells, produced potent inhibitory effects on the induction of Epstein-Barr virus (EBV)-EA by 12-0-tetradecanoylphorbol-13-acetate (TPA). The doses of a- and P-CBT required for 50% inhibition of EBV-EA induction by TPA were 7.7 and 6.7 mg/mL, respectively. Application of a- and P-CBT to mouse skin before treatment with TPA, inhibited TPA-induced ornithine decarboxylase activity in a dose-dependent manner. Application of 16.5 pM/mouse of a- and p-CBT resulted... 

The in vitro EBV-EA activation inhibition assay uses EBV genome-carrying lymphoblastoid cells (Raji cells derived from Burkitt s lymphoma). Many compounds which inhibit EBV-EA induction by tumor promoters have been demonstrated to act as inhibitors of tumor promotion in vivo [16,22,42,66-68]. This assay has an advantage since it obtaines the information on die cytotoxicity from the viability of Raji cells. High viability of these cells is an important factor in developing a compound for the chemoprevention of cancer [16]. So far, a number of triterpenoids and steroids from plants and their derivatives have been shown to possess... 

Enhancement of the inhibitory activity was found in 3-oxo derivatives of 142 and 210, while either loss of oxygen functionality at C-3 of 210 or oxidation at C-3 of 147 led to the reduction of the activity [22]. Two 3-O-acetyl oleananes, 3-O-acetylerythrodiol (117 68% inhibition at lxlO3 mol ratio compound/TPA 80% cell viability) and acetyloleanolic acid (119 64% inhibition 80% viability), showed remarkable inhibitory effects with preserved higher viabilities of Raji cells than their free alcohols, erythrodiol (130 81% inhibition 50% viability) and 142 (70% inhibition 60% viability) [72]. Under the same assay conditions, betulinic acid (257) exhibited complete inhibition of activation with 80% cell viability [72]. Arjunolic acid triacetate (154 66% inhibition at lxl02 mol ratio compound/TPA) and arjunolic acid triacetate methylester (155 73%)... 

Twenty-three triterpenoid hydrocarbons isolated from ferns were screened [67]. The following eight exhibited strong inhibitory effects at lxlO2 mol ratio compound/TPA with >80% viability of Raji cells [67]. They are multiflor-8-ene (220 45%), multiflor-9(ll)-ene (228 41%), taraxastane (237 43%), taraxerane (241 37%), glutin-5(10)-ene (244 52%), hop-17(2l)-ene (275 51%), neohop-13(18)-ene (277 37%), and neohop-12-ene (278 37%). It should be mentioned that the inhibitory... 

Soyasapogenol B, soyasaponins I and II and wistariasaponins from Wistaria brachybotrys (wistariasaponin C corresponds to astragaloside VIII) decreased (20-30%) the Epstein-Barr Virus (EBV) activation induced by the tumor promoter TPA (12-O-tetradecanoylphorbol-13-acetate) in Raji cells at a concentration of lxlO2 mol ratio [151]. Soyasaponin I from the same plant exhibited remarkable inhibitory effects on mouse skin tumor promotion on the basis of the two-stage DMBA-TPA carcinogenesis test in vivo. Soyasaponin I reduced the number of papillomas per mouse at about 40% even at 20 weeks [152]. 

Chen Y, Shu W, Chen W, Wu Q, Liu H, Cui G. 2007. Curcumin, both histone deacetylase and p300/CBP-specific inhibitor, represses the activity of nuclear factor kappa B and Notch 1 in Raji cells. Basic Clin Pharmacol Toxicol 101 427 433. 

Sun CY, Liu XY, Chen Y, Liu F, Wang Y. 2004a. Experimental study on anticancer effect of curcumin on Raji cells in vitro. Zhongguo Zhong Xi Yi Jie He Za Zhi 24 1003-1006. 

Wu Q, Chen Y, Li X. 2006. HDAC1 expression and effect of curcumin on proliferation of Raji cells. J Huazhong Univ Sci Technolog Med Sci 26 199-201, 210. 

To investigate the specificity of DGAT inhibitors, synthesis of lipids including TG, phosphatidylcholine (PC), and phosphatidylethanolamine (PE) was measured in an intact cell assay using Raji cells by our established method [54], Raji cells are incubated in the presence of [14C]oleic acid with or without a test sample in a total volume of 0.2 ml. After a 20-min incubation at 37°C, [14C]oleic acid is incorporated mainly into PC, PE, and TG, which are extracted and separated by TLC. The distribution of radioactivity in these lipids on TLC is analyzed. 

If the sample inhibits DGAT activity specifically in Raji cells, incorporation of [14C]oleic acid only into the TG fraction should be inhibited. 

Table 2 Inhibition of Triacylglycerol Synthesis by DGAT Inhibitors in Assays Using Rat Liver Microsomes and Intact Raji Cells...

Foremost among these assays is the Raji cell assay developed by The-ofilopoulos and co-workers (T15). The Raji cell line, derived from a patient with Burkitt s lymphoma, lacks surface immunoglobulin, has Fc receptors that bind monomeric IgG only weakly, and possesses numerous receptors for Clq, C3b/C4b, C3d, and other complement components (G23, S4, S27, S28, T8, T12). Immune complexes which have fixed complement bind to... 

A13, Anderson, C. L., and Stillman, W. S., Raji cell assay for immune complexes. Evidence for detection of Raji-directed immunoglobulin G antibody in sera from patients with systemic lupus erythematosus. J. Clin. Invest. 66, 353-360 (1980). 

H24. Horsfall, A. C., Venables, P. J. W., Mumford, P. A., and Maini, R. W., Interpretation of the Raji cell assay in sera containing antinuclear antibodies and immune complexes. Clin. Exp. Immunol. 44, 405-415 (1981). 

T14. Theofilopoulos, A. N., Wilson, C. B., Bokisch, V. A., and Dixon, F. J., Binding of soluble immune complexes to human lymphoblastoid cells. II. Use of Raji cells to detect circulating immune complexes in animal and human sera. /. Exp. Med. 140, 1230-1244 (1974). 

Several terpenoids have been evaluated for their inhibitory effects on EBV-EA activation induced by TPA. Table 6 shows the inhibitory effects of monoterpenoids [70,71], sesquiterpenoids [20,119-123], diterpenoids [21,123-131], and meroterpenoids [117] against TPA (32 pmol, 20 ng)-induced EBV-EA activation in Raji cells. The inhibitory effects were compared with that of [3-carotene, a vitamin A precursor that has been studied intensively in cancer chemoprevention using animal models [2,4]. All of the terpenoids tested caused higher viability (60-80%) of Raji cells even at mol ratio of compound to TPA = 1000 1 indicating their very low cytotoxicity at that high concentration (refer to Table 6). 

After electroporation into Raji cells, CD4 antigen-positive cells are enriched by repeated cell sorting and plasmids are recovered in Escherichia coli. Individual plasmids are retransfected and clones that induce expression of CD4 antigen on the cell surface were identified. Positive clones are sequenced and their deduced amino acid sequences are examined for the presence of a signal peptide. If a stretch of hydrophobic amino acids is detected immediately... 

Electroporation of a Signal Sequence Trap Library into Raji Cells... 

Maintain Raji cells in RPMI-1640/10% fetal calf syndrom (FCS) in a humidified 37°C, 5% C02 incubator. Before the day of electroporation, dilute the culture 3X to ensure that the cells are in logarithmic growth phase. 

In our experience, about 106 stable transformants were routinely obtained from 107 Raji cells. Therefore, in order to obtain a population that represents the full cDNA library, perform one electroporation with 107 Raji cells/2 x 105 independent E. coli colony. 

Raji cells are weak to exposure to the cold environment. Therefore, we perform all the manipulation at room temperature. 

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