Tissue formation from heterogeneous cell types, similar to those in vivo, is an important technique for development of new drugs and formation of artificial organs. In vivo tissues are complex arrangements of heterogeneous cells that interact with each other. To create such tissues in vitro, it is essential to develop a technique that arranges heterogeneous cells in an arbitrary configuration. Currently, we are developing a new gel patterning technique to create effective cell micropatterns by using photolithography and alginate gel, which inhibits cellular adhesion. In this study, we considered that a more flexible gel patterning technique was required for creating order-made formations of complex tissues. We created gel patterns by removing the alginate gel using laser processing, and cells were cultured on the formed patterns. Complex heterogeneous cell patterns were achieved by adjusting various technical parameters such as the laser power, spot diameter, and alginate gel film thickness. Based on our results, we anticipate that our technique will prove useful for the development of regenerative medicine and tissue engineering.

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