The use of LPS antagonists to reduce the pathophysiological effects of LPS released during gram negative sepsis is a promising approach to the treatment of septic shock for which current therapies have very limited clinical impact. In order to identify novel LPS antagonists we are developing a rapid microtiter plate-based assay for use in the primary screening of such compounds. This assay relies on the use of the human inducible nitric oxide synthase promoter (iNOS) to drive the expression of the reporter green fluorescent protein (GFP) in a monocytic cell line to detect LPS antagonist. This iNOS/GFP reporter construct will produce GFP fluorescence in response to LPS, which induces macrophage activation. These attributes of the assay will facilitate the identification of LPS antagonists with desirable therapeutic properties.
In collaboration with pharmaceutical companies we intend to use this assay as high-throughput screen on libraries of compounds for novel LPS antagonists. In addition to natural products which have been a traditional source of LPS antagonists, synthetic compound, combinatorial oligonucleotide or peptide, and phage display libraries will be screened with this assay.
