System for cell-based screening

An automated method for identifying compounds that modulate internalization of cell surface receptor proteins comprising:

• providing an array of locations containing multiple cells to be treated with a test compound, wherein the cells possess at least a first luminescently labeled reporter molecule that reports on a cell surface receptor protein of interest and at least a second luminescently labeled reporter molecule that identifies cells, and wherein the cell surface receptor protein is either expressed as a luminescently labeled protein, or is luminescently labeled by contacting the cell with a luminescently labeled molecule that binds to the cell surface receptor protein, wherein the contacting can be carried out either before or after treatment with the test compound;
• contacting the cells with the at least a second luminescently labeled reporter molecule, wherein the contacting can be carried out either before or after treatment with the test compound;
• treating the cells with the test compound;
• imaging multiple cells in the array of locations;
• automatically obtaining luminescent signals from the at least second luminescently labeled reporter molecule to identify cells;
• automatically obtaining luminescent signals from the at least first luminescently-labeled reporter molecule on or in the cells, comprising:
• a) acquiring an object image of the at least first luminescently labeled reporter molecule on or in the individual cells;
• b) by segmenting the object image to produce a segmented object image;
• and
• c) calculating whether objects in the segmented object image meet or surpass a user-defined threshold luminescent intensity value, wherein an object that meets or surpasses a user-defined threshold luminescent intensity value represents an internalized cell surface receptor protein of interest:
• converting the luminescent signals into digital data;
• and
• automatically calculating from the digital data:
• i) a total number of cells, calculated from the digital data from the at least second luminescently labeled reporter molecule;
• and
• ii) a number and/or percent of cells that internalized the at least first luminescently labeled reporter molecule;
• wherein the calculations provide a measure of whether the test compound has modulated internalization of the luminescently labeled cell surface receptor protein.