PROBLEM TO BE SOLVED: To obtain a new cell line of the cultivated cell line of a silkworm having serially passaged properties and stably propagating within a specific temperature range, capable of being kept stable at a nonconventional high temperature, useful for elucidation, or the like of physiological biofunctions of an insect, and having simplified construction of tissue and organ of a polypide.
SOLUTION: This new cell line is a new serially passaged culturing cell line of a silkworm, capable of stably propagating within the temperature range of 25-37°C, and derived from the embryonic tissue of the silkworm. The cell line is selected from NISES-BoMo-MK (FERN P-17391), NISES-BoMo-DZ (FERM P-17389), NISES-BoMo-OH (FERM P-17392) and NISES-BoMo-KG (FERM P-17390). The cell line has a more simplified construction of tissue and organ of a polypide, and is useful for elucidation, or the like, of physical biofunctions of the insect. The culturing cell line is obtained by culturing the cells obtained from embryonic tissue of the silkworm at 25-270°C to establish the first culture, culturing the first-cultured product by changing the temperature to 37°C in the second culture, and further culturing the survival cells again.