A new paradigm considering multicellular adhesion, repulsion and attraction represent diverse cellular tile patterns

Cell sorting by differential adhesion is one of the basic mechanisms explaining spatial organization of neurons in early stage brain development of fruit flies. The columnar arrangements of neurons determine the large scale patterns in the fly visual center. Experimental studies indicate that hexagonal configurations regularly appear while tetragonal configurations can be induced in mutants. Mathematical models based on macroscopic approximations of agent based models (ARA models) are shown to produce a similar behavior changing from hexagonal to tetragonal steady configurations when medium range repulsion and longer-range attraction between individuals is incorporated in previous successful models for cell sorting based on adhesion and volume constraints. We analyse the angular configurations of these patterns based on angle summary statistics and compare between experimental data and parameter fitted ARA models showing that intermediate patterns between hexagonal and tetragonal configuration are common in experimental data as well as in our ARA mathematical model. Our studies indicate an overall qualitative agreement of ARA models in tile patterning and pave the way for their quantitative studies. 2010 MSC92C17, 92C37, 35Q92