Establishment of cell lines from the wild rodent Millardia meltada and tests for endogenous virus.

Four cell lines were established from the wild rodent, Millardia meltada; an untransformed cell line (MM-D), a non-producer (NP) cell line transformed with murine sarcoma virus (MM-CL4), and SV40-transformed cell lines (MM-8 MM-663). MM-D is epithelioid and contact-inhibited, whereas MM-CL4, MM-8, and MM-663 are fibroblastic and grow piling up. No endogenous virus was induced in Millardia cell lines by a long-term culture with various inducers. Millardia cell DNA has no nucleotide sequence homology with cDNA of either murine leukemia virus or rat endogenous virus.