Investigation of cell localisation pattern in 3 dimensional micro-tissues

It is impossible to mimic mammalian tissues by classical two-dimensional (2D) techniques. In this study, it is aimed to take advantage of self-assembly characteristics of cells in physiological conditions to achieve 3D tissues in vitro. Human Osteosarcoma cells (SaOS-2) were co-cultured with human umbilical vein endothelial cells (HUVEC) and human skin fibroblast cells (Detroit) were co-cultured with human skin keratinocyte cells (HS2) in agar gels that were formed using 3D Petri Dish^® technique, and localization of cells were examined. Affect of cell number on localization was also investigated via using different cell ratios in co-culture systems. The change over time in the size of micro-tissues was determined using ImageJ program. The fluorescence microscope examination revealed that in SaOS-2 - HUVEC co-culture system, cells were localized randomly, and there wasn´t any significant effect of cell number on localization pattern. In HS2 - Detroit co-culture system, fibroblasts were localized in the core and the keratinocytes were found on the outer shell, and cell number didn´t affect this pattern. In microtissues formed by HS2 - Detroit co-culture, there was a significant increase in size after 72 hours. In the SaOS-2 - HUVEC co-culture, there was a significant reduction between the first and the fifth hours.