Immortalization of growth factor-dependent mouse splenic macrophages derived from cloned progenitors

We describe a nonviral transformation strategy for the establishment of permanent cell lines derived from the progeny of individual mouse splenic macrophage (M Φ) progenitors. These colony stimulating factor-1 (CSF-1)-dependent cell lines possess many features of mature M Φs, including antibody-dependent phagocytic and cellular cytotoxic activities, ability to secrete lysozyme, and expression of the Mac-1 antigen and mRNA for the CSF-1 receptor. It was also possible to immortalize selected clones of splenic M Φs differing in their constitutive antigen-presenting activities with the retention of the antigen-presenting phenotype in the resultant cell lines. The approach described in this report should be useful in obtaining additional cell lines of M Φs expressing other phenotypes of interest.