Decreasing Immune Competence and Development of Reticulum Cell Sarcomas in Lymphatic Tissue of Aged Mice2

Abstract

The relation between the development of reticulum cell sarcoma and the reduced immune capacity in aged (C57BL/6× C3H/An)F₁ (B6C3F₁) mice was studied. ¹²⁵l-human γ-globulin (HGG) was used to analyze the relative immune clearance and antigen-trapping capacity of spleen germinal centers in 1.5-year-old, 2.5-year-old, and 13-week-old mice; the histopathologic development of reticuloendothelial neoplasia was determined with respect to its site of origin within the lymphatic nodules of the spleen. The results of these studies are: 1) The decrease in immune capacity in these aged mice is clearly not a function of the development of lymphoreticular neoplasia. However, impaired immune competence may be related causally to the subsequent development of lymphatic and non-lymphatic tumors. 2) Immune clearance and antigen localization in germinal centers of 1.5-year-old mice are markedly depressed. No immune clearance was detected in the 2.5-year-old animals, and antigen localization is extremely rare. 3) The reticulum cell sarcoma of the B6C3F₁ originates in the thymus-dependent periarteriolar region of the spleen lymphatic nodules. This is followed by invasion of anaplastic reticular cells into the cortical region of the nodule and spleen red pulp. 4) It is suggested that “mesenteric lymph node disease” is a degenerative disease associated with antigenic burden.