Defining and Assessing Analytical Performance Criteria for Transmissible Spongiform Encephalopathy-Detecting Amyloid Seeding Assays.

Transmissible spongiform encephalopathies (TSEs) are infectious, fatal neurodegenerative diseases that affect production animal health, and thus human food safety. Enhanced TSE detection methods mimic the conjectured basis for prion replication, in vitro; biological matrices can be tested for prion activity via their ability to convert recombinant cellular prion protein (PrP) into amyloid fibrils; fluorescent spectra changes of amyloid-binding fluorophores in the reaction vessel detect fibril formation. In vitro PrP conversion techniques have high analytical sensitivity for prions, comparable with that of bioassays, yet no such protocol has gained regulatory approval for use in animal TSE surveillance programs.

Performance analysis of rapid diagnostic tests on atypical bovine spongiform encephalopathy.

The preferred method to determine the prevalence of bovine spongiform encephalopathy (BSE) in a country is to use immunology-based rapid-tests. Though these tests are validated to detect C-type BSE disease-associated prion (PrP(sc)), test-specific properties may influence their ability to detect H- and/or L-type BSE PrP(sc), where both are atypical from C-type PrP(sc). Molecular characterization shows atypical BSE PrP(sc) to have a different sensitivity to proteinase activity and different affinities for certain prion-specific antibodies.

A study on the analytical sensitivity of 6 BSE tests used by the Canadian BSE reference laboratory.

Bovine spongiform encephalopathy (BSE) surveillance programs have been employed in numerous countries to monitor BSE prevalence and to protect animal and human health. Since 1999, the European Commission (EC) authorized the evaluation and approval of 20 molecular based tests for the rapid detection of the pathological prion protein (PrP(sc)) in BSE infection. The diagnostic sensitivity, convenience, and speed of these tests have made molecular diagnostics the preferred method for BSE surveillance.

Discovery of novel nuclear receptor modulating ligands: an integral role for peptide interaction profiling.

There is currently a marketed drug for nearly every nuclear receptor for which the natural ligand has been identified. However, because of the complexity of signal transduction by this class of ligand-regulated transcription factors, few of these drugs have been optimized for pharmaceutical effectiveness. Over the past several years, structural and biochemical work has shed light on some of the ligand-induced features of nuclear receptors that enable them to trigger signal transduction cascades.

Correlation between in vitro peptide binding profiles and cellular activities for estrogen receptor-modulating compounds.

Numerous biochemical and structural studies have shown that the conformation of the estrogen receptor alpha (ERalpha) can be influenced by ligand binding. In turn, the conformational state of ERalpha affects the ability of the receptor to interact with a wide variety of protein accessory factors. To globally investigate ligand-based cofactor recruitment activities of ERalpha, we have applied a flow cytometric multiplexed binding assay to determine the simultaneous binding of ERalpha to over 50 different peptides derived from both known cofactor proteins and random peptide phage display.