Digital Image Analysis: Colocalization



Colocalization is defined as the presence of two or more different molecules at the same location within a cell.

In practice, colocalization is indicated when two or more fluorescent markers of cellular structures overlap in the final image.

For example, the fluorescent label of the red and green channel were overlayed and colocalization is assumed for those structures showing a yellow color in the composite image. However, this simple method is only a first visual estimate and is not appropriate for quantification as demonstrated under "overlay methods".




Metaphysiol offers quantitative colocalization analysis of multiply labeled fluoescent images. The analysis includes intensity correlation coefficient based methods (see ICCB) and object based approaches.