Experimental and Computational study of the growth and interfacial behavior of cells cultures

E. V. ALBANO; GUISONI, N.; B. MOGLIA; A.M. HUERGO

Cartagena de Indias

Workshop; XIV Latin American Workshop on Nonlinear Phenomena (LAWNP); 2015

Universidad de Bogota

The growth of cell colonies is investigated byperforming both In Vitro cultures and computer simulations. The interfacialproperties of the colonies are rationalized in terms of the dynamics scalingtheory [1]. Two different cell lines are studied: Vero and HeLa cells.Experiments show that the front of Vero (HeLa) cell colonies moves forward withan average constant velocity of v = 0.22 ± 0.02 mm/min (v = 0.9 ± 0.05 mm/min).The dynamic scaling analysis [1] of both cultured cell colonies, shows that plotsof the width of the interface (W) versus the time (t) collapse in a singlecurve with a growth exponent  β =0.33(2). From the structure factor a global roughness exponent α = 0.50(5) isobtained, so that the dynamic exponent is z = 1.5(2). Also, the analysis of numericalsimulations of discrete model for cell cultures in-vitro, aimed to describe theexperimental setup, yields β = 0.32(2), α = 0.49(5), and z = 1.49(2). Summingup, we conclude that there is an excellent agreement between the experimentaland the numerical results. Furthermore, the set of evaluated exponents fulfilsthe Family-Vicsek[1] relationship and it is consistent with the predictions ofthe Kardar-Parisi-Zhang (KPZ) [2] equation (β= 1/3,  α =1/2 , and z = 3/2), so that the growinginterface can be placed within the KPZ universality class [1,2].By considering cultures in a quenched noiseenvironment we found the in the low-noise regime the interface is free and alsobelongs to the KPZ universality class. However, by increasing the noise the interfacebecomes pinned, the coefficient of the nonlinear term of the KPZ equation [1,2]vanishes and the pinned interface belongs to the Quenched Edwards-Wilkinson [1]universality class, with   α = 1.03(4) ,β = 0.81(3) , and  θ = 0.20(3). [1] L. Barabasiand H.E. Stanley. Fractal Concepts in Surface Growth, CambridgeUniversity Press, Cambridge (1995).[2] M.Kardar, G. Parisi, and Y.-C. Zhang, Phys. Rev. Lett. V56}, 889 (1986).