Isolation of cell lines from embryos of the cockroach, Blattella germanica.

Cell lines were isolated from three stages of embryos of Blattella germanica dissociated with trypsin. The lines have been subcultured 50 to 134 times in 3 years. Line UM-BGE-1 was isolated from germ band embryos at stages of segmentation and limb-bud formation (5 days old). Line UM-BGE-2 was derived from embryos at dorsal closure (7 days old). Line UM-BGE-4 arose from embryos in the germ band and dorsal closure stages (5 and 7 days old): these cells colonize as hollow spheres or vesicles. Line UM-BGE-5, isolated during organogenesis (10 days old), developed into two distinct sublines. Subline alpha is composed of round cells that do not attach to the flask. Subline beta grows as an attached monolayer; the cells can be removed with a saline solution containing 20 mM disodium dihydrogen Versenate. Most of the cells of these lines have the diploid chromosome number (23 or 24) excepting line UM-BGE-1 in which the tetraploid number predominates