As part of our work on using 3d printing and cell culture, we intend to grow hFOB 1.19 cells onto 3d printed bone models. hFOB 1.19 is an osteoblast cell line used to study human osteoblast differentiation. Successful attachment and proliferation of osteoblasts onto 3d printed components would have the potential to improve bone and orthopedic injury treatments. A dual-marker labeling system using promoter specific expression of fluorescent tags, allows for positive identification of osteoblasts and facilitates imaging of cells. A dual plasmid CRISPR knock-in system was designed for insertion of markers into the hROSA26 locus of the osteoblast cells.