Histology of the Reticuloendothelial System of the Spleen in Mice of Inbred Strains2

Abstract

The histologic structure of the reticuloendothelial system of the spleen of mice of inbred strains was studied with a silver impregnation technique. The reticuloendothelial cells in the spleen form a general pattern common to all strains of mice examined. A central structure is formed by parallel rows of fibers and reticuloendothelial cells disposed around the follicular artery. Distributed throughout the follicle are scattered reticuloendothelial cells. At the periphery of the follicle the reticuloendothelial cells form a collar surrounding it. In the space between the collar and the red pulp is an area filled with sinusoids and a few reticuloendothelial cells. This space stains lightly with silver, appearing as a halo around the follicles. In the red pulp, the reticuloendothelial cells do not form geometric patterns as they do in the follicles. The morphological structure and arrangement of the reticuloendothelium are characteristic for each strain of inbred mice examined. The differences by which the strains are distinguished depend on the pattern of the reticuloendothelium in the splenic follicles. No quantitative difference was detected and the number of cells appeared to be roughly equivalent in all strains. Susceptibility to spontaneous tumor development could not be correlated with the structural differences found, though in strains highly susceptible to the development of leukemia the germinal centers of the splenic follicles were prominent, and their reticuloendothelial cells were abundant and large.