Investigation into the origin of mouse liver sinusoidal cells

The possibility that liver sinusoidal cells are derived from the bone-marrow was investigated in chimeric mice. H2k-positive bone-marrow cells from F1 (B10.BR X B10.D2) hybrid mice were transplanted into irradiated H2k-negative parental mice (B10.D2), and the liver examined immunohistochemically for the presence of H2k-positive cells, with the help of an anti-H2k monoclonal antibody. With the passage of time (from the fifth week onwards), increasing numbers of transplanted bone-marrow cells enter the liver sinusoids, undergo alteration in their shape, and remain there, probably replacing sinusoidal lining cells. DNA-synthesising cells in the sinusoids were observed, suggesting, in addition, local cell proliferation. The replacement of sinusoidal cells from bone-marrow was greatly accelerated after liver damage had been induced by sublethal doses of endotoxin (LPS), and proliferation was also enhanced after treatment with LPS. These results strongly suggest that the bone-marrow participates in the replacement of liver sinusoidal cells.