Nomenclature
The '3T3' designation refers to the abbreviation of "3-day transfer, inoculum 3 x 105 cells." This cell line was originally established from the primary mouse embryonic fibroblast cells that were cultured by the designated protocol, so-called '3T3 protocol'. The primary mouse embryonic fibroblast cells were transferred (the "T") every 3 days (the first "3"), and inoculated at the rigid density of 3 x 105 cells per 20-cm² dish (the second "3") continuously. The spontaneously immortalized cells with stable growth rate were established after 20-30 generations in culture, and then named '3T3' cells. Specifically, "3T3-L1" is one of the current line.
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