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The generation of macrophage-like cell lines by transfection with SV40 origin defective DNA.

Two cell lines with properties of mature macrophages have been generated by transfection with SV40 DNA mutated in the origin of replication. One line, BAM, was derived from bone marrow cells from a BALB/c mouse. The other line, BAC1, was derived from splenic adherent cells from a (BALB/c X A.CA) F1 mouse. Both lines produce lysozyme, collagenase, and esterase, bear Fc receptors, and engage in Fc-mediated phagocytosis. Both lines require colony-stimulating factor-1 for continued proliferation. In addition, they express Ia antigens, and may be induced to secrete IL 1. This technique should make possible the generation of Ia-bearing diploid macrophage lines from any strain of mouse. In addition, it may be possible to use this technique to derive monocyte lines from species in which wild-type SV40 DNA causes a lytic infection.