Production of Interferon by an SV40‐Transformed Macrophage Line, BB‐W‐531–2

A simian virus 40-transformed mouse macrophage line, BB-W-531-2, was examined for its ability to produce interferon. BB-W-531-2 cells showed a phenotypic change between the macrophage and the nonmacrophage states. A viral inhibitor (interferon) was produced by the cells during the phenotypic change from the nonmacrophage to the macrophage state. Cells having macrophage properties were well capable of producing interferon when they were stimulated with ultraviolet-inactivated vaccinia virus, lipopolysaccharide, a streptococcal preparation (OK-432) or polyinosinate . polycytidylate. In contrast, cells that had lost their macrophage properties did not produce interferon even when they were given the same treatments as the cells having macrophage properties. The results suggest that the ability of BB-W-531-2 cells to produce interferon is associated with the expression of several macrophage properties.