Patent ID: 8178058

Claim:
A method of detecting a target specific reagent comprising the steps of: a. selecting a cell having a selected target molecule located in a position selected from the group consisting of a cell wall or inside the cell, b. culturing the cell on a multiwell filter plate, wherein the filter plate has low background fluorescence, and pores which permit the cell to be cultured on the plate and washed in situ by gravity; c. contacting the cell with a reagent while in the filter plate wherein the reagent is a primary ligand for a selected target molecule of the cell, d. washing the cell while in the filter plate with gravity flow at least one time to remove any primary ligand which is not bound to the selected target molecule of the cell by using sufficient fluid to achieve a head height at which filtration occurs, e. adding a secondary ligand having a detectable marker and the secondary ligand is capable of attaching the primary ligand, f. washing the cell while in the filter plate with gravity flow at least one time to remove any secondary ligand which is not bound to the selected target molecule of the cell by using sufficient fluid to achieve a head height at which filtration occurs, to provide a washed cell; and g. detecting for the presence or absence of the detectable marker of the secondary ligand to indicate the presence or absence of the target molecule in or on the washed cell on the multiwall filter plate.