title: Rapid aggregation of heterogeneous cells and multiple-sized microspheres in methylcellulose medium.
abstract: We report a method for the rapid production of cellular aggregates without electric power and cell modification. We focused on the swelling property of a solution containing a high molecular material, methylcellulose (MC), which immediately absorbs a small amount of solvent and fills the space occupied by the solvent. When 1 μl of a suspension of 1000 animal cells in normal culture medium was injected into the 3% MC medium, the normal medium was rapidly absorbed by the surrounding MC medium. Suspended cells were simultaneously trapped on the interfaces between the normal and MC media; they were finally pulled together and held in the MC medium. This event was nearly complete within the first 10 min. Moreover, MC medium-dependent aggregation was observed when polystyrene microspheres of different sizes (diameter, 100 nm-100 μm) were added. Furthermore, we demonstrated the stepwise fabrication of multi-layered aggregates with embedded structures. These methods for creating engineered aggregates should enhance the study of three-dimensional cultures comprising two or more cell types with well-designed structures.
authors.affiliation: Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan. nobuhiko@iis.u-tokyo.ac.jp
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Kojima
authors.forename: Shoji
authors.initials: S
authors.lastname: Takeuchi
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Sakai
mesh_terms: D000818:Animals; D002449:Cell Aggregation / Q000187:drug effects*; D018929:Cell Culture Techniques / Q000379:methods; D002478:Cells, Cultured; D003470:Culture Media / Q000494:pharmacology; D056945:Hep G2 Cells; D006801:Humans; D008747:Methylcellulose / Q000494:pharmacology*; D051379:Mice; D008863:Microspheres; D041681:NIH 3T3 Cells; D053758:Nanoparticles / Q000737:chemistry
chemical_list: D003470:Culture Media; D008747:Methylcellulose