Target cell-based screening

Hsieh AC, Bo R, Manola J et al (2004) A library of siRNA duplexes targeting the phos-phoinositide 3-kinase pathway determinants of gene silencing for use in cell-based screens. Nucleic Acids Res 32 893-901... 

Evans MJ, Saghatelian A, Sorensen EJ et al (2005) Target discovery in small-molecule cell-based screens by in situ proteome reactivity profiling. Nat Biotechnol 23 1303-1307... 

Small molecule carbohydrates, lipids, natural products, drugs, drug-like molecules synthesis platform, ligand discovery, antibody binding screens, enzymatic assays, phenotypic cell-based screens, diagnostics, target deconvolution 12, 14-16, 21, 22, 25-32, 39, 40, 43, 44, 46, 48, 53, 55-65, 78... 

The next issue in the drug discovery process following definition of target and sources of diversity is the definition of a lead structure. Lead structures can arise from biochemical or cell-based screens or through structure-based design. Broach and Thorner provide a more exhaustive description of screening strategies than is possible here (14). 

While cell-based screens have been used in purely empirical screening efforts, they can also be used as the basis of target identification or verification. The... 

A major problem of cell-based screening assays is that cytotoxicity derived from mechanisms unrelated to the target of interest prevents further evaluation of a compound or, more feasible, of an extract from natural sources. Furthermore, depending on the assay endpoint, false positives may be selected. Therefore, secondary assays are required to eliminate cytotoxic false positives as well as to prove the mode of interaction that gave positive endpoint detection in the screening assay. 

Profile Cellomics Inc., formerly BioDx Inc., is a privately held corporation founded in October 1996. Cellomics mission is to improve the efficiency of the drug discovery process by delivering a cell-based screening platform that automates target validation and lead optimization using fluorescence-based assays. 

In total, we have 24 different potential targets for the 9 GRAS molecules. For the sake of cost effectiveness and efficiency, we chose to employ a RAW 264.7 cell model—as described in the Materials and Methods section— to validate experimentally the putative anti-inflatmnatory effects of our compounds. This high-content assay allows one to measure several important inflammation-related parameters, such as NO, TNF-o, IL-1, IL-6, and PGE-2 activities. In our test assays, we also included compounds such as resveratrol as references, since it is known to have anti-inflammatoiy effects in this cell-based screening system as well as in other in vitro and in vivo models. Compounds were evaluated according to their maximum nontoxic concentration according to MTS assay (Table 4.4). 

---