Migration distance

Radial migration distance is defined as the average distance between the rim of the sphere-core and the furthest migrated cells. Thus migration distance is assessed by recognizing the sphere-core and defining it as the inner border of the migration area. The outer border is identified by using the density of coordinates of the identified centroids of cell nuclei and the intensity information of the nucleus channel. The migration distance is subsequently calculated as the mean distance between these two borders. Since only the raw images and the centroids of cell nuclei are required to assess this endpoint, centroids of cell nuclei obtained by different methods can be imported in Omnisphero and used for the evaluation.

Migration Distance
Assessment of the migration distance: The sphere core is the brightest object within the migration area and is automatically removed by Omnisphero. The removed sphere-core defines the inner border of the migration area. The density of nuclei centroids is used to identify the outer border of the migration area (a). The right image shows the resulting mask of the migration area overlapped on the original image (b).