Bio-cell chips are microarrays, which are composed of collections of cell spots attached to the surface. They hold intact cells and therefore enable the study of gene-gene interactions and gene-protein interactions in a cell with three-dimensional positional information. The authors developed a 16 x 6 array bio-cell chip comprising a 1-mm-thick perforated polydimethylsiloxane (PDMS) layer on lattice-patterned 25 mm x75 mm glass slide. The perforations in the PDMS layer formed cylindrical wells of volume approximately 1.7 micro L, which were used to seed cells. The authors constructed bio-cell chips using mononuclear cells from bone marrow specimens and subjected them to fluorescent in situ hybridization (FISH). Bio-cell chip technology is compatible with standard clinical diagnosis protocols, requires smaller samples, provides results quickly, and is highly cost-effective. In addition, bio-cell chips can be used as a platform for distributing real samples for research purposes. These features make it a potential tool for basic research and for clinical diagnosis.