Patent ID: 8426123
Filing Date: 2013-04-23
Classification: G01N

Abstract:
1. A method for conducting a neutralization assay for the titer of antibodies in a sample, which antibodies are specific for a predetermined target molecule that activates the signal transduction activity of a cell surface protein or pattern recognition receptor, said method comprising: preparing a serial dilution of the sample; adding to each dilution a fixed amount of the target molecule, which amount corresponds to a predetermined unit of activity of the target molecule, and wherein the concentration of target molecule is the same in each dilution; subjecting each dilution to a reporter gene assay to determine the amount of residual activity of the target molecule in that dilution, wherein said reporter gene assay comprises measuring the level of reporter gene product upon contact of said dilution with a cell line transformed with a construct comprising a nucleotide sequence encoding a reporter gene product, operatively linked to one or more transcription control elements that is regulated by the signal transduction activity of a cell surface protein or pattern recognition receptor in response to an extracellular signal generated by said target molecule; and determining the dilution at which the activity of the added target molecule is reduced by a predetermined factor, x, said titer being expressed as an x-fold reduction in units of activity/ml, wherein the cell line used in said reporter gene assay is one that has been treated with an anti-mitotic or pro-apoptotic agent so as to acquire the property that it will maintain said signal transduction activity for at least about one hour but will lose said signal transduction activity and undergo cellular death in no more than about 30 days at a temperature above freezing, thereby improving the sensitivity of the neutralization assay.