Fig. 4

Computation of the border between two mammalian cell populations. The sender/receiver population (pHW074, pSTAT6, pHW040, and pMK047 as a seeding control) was seeded in the outer compartment of a 60 mm culture dish with an insert, while the processing population (pWB024 and pHW073 in a ratio (w:w) of 100:1) was seeded in the inner square-shaped compartment. The cells were overlaid with agar-solidified InVitrus medium supplemented with 500 μM indole and cultivated for 48 h before microscopic analysis of expression of the YFP reporter (column c)). Control cells were overlaid with agar-solidified InVitrus medium without indole (column b)) or with agar supplemented with 50 μM L-tryptophan (column d)) or 10 ng ml⁻¹ interleukin-4 (column e)). Background level of YFP expression of the sender/receiver cell population is presented in column a), where the population was seeded in the absence of processing cell population and medium supplements. The top row shows the expression of the fluorescent reporter protein YFP that is displayed as heat maps in the middle row. The bottom row shows the total cell distribution of the sender/receiver cell population constitutively expressing the fluorescent reporter protein mCherry, whereas the dark squares in the center are the inner compartments. Scale bar = 5 mm