Increase of GM-CSF responsive cells in organs of systemic lupus erythematodes -SLE- developing mice

Our investigations of the macrophage system in systemic lupus erythematodes developing mice, have revealed increased numbers of macrophages in the liver of lupus prone mouse strains. This phenomenon was already shown in phenotypically unaffected, four weeks old mice. Based on these results we studied the proliferation of different organ-associated macrophage populations from mice at an age of four weeks and stimulated the cells with recombinant murine GM-CSF. In these experiments only a slightly increased proliferation under the influence of GM-CSF was observed. The incubation of non parenchymal liver cells in the presence of indomethacine, however, resulted in an increased spontaneous and GM-CSF induced proliferation in the autoimmune strains. The latter was found also in spleen and bone marrow derived cells. Our results implicate an enhanced number or an increased proliferation of GM-CSF responsive cells in the organs from autoimmune mice in comparison to mormal control mice.