Morphological Study of Mesenteric Lymph Nodes in Rats with Experimental Breast Cancer Treated with Fragmented Double-Stranded DNA.

We performed a morphometric analysis of mesenteric lymph nodes in rats with breast cancer induced by administration of N-methyl-N-nitrosourea. The volume of the paracortical zone and the number of mature plasma cells in the medullary sinuses were increased and the volume of lymphoid nodules with germinal centers and the number of macrophages were decreased in the group with tumor resection and chemotherapy in comparison with untreated rats with breast cancer. In rats receiving fragmented human double-stranded DNA in combination with adjuvant therapy, the volume of marginal and medullary sinuses and the number of small lymphocytes and macrophages in the paracortical zone increased in comparison with the group receiving chemotherapy without DNA preparation; the volume of lymphoid nodules with germinal centers returned to the level observed in the intact group; the volume of medullary substance and proliferative activity of cells in the germinal centers and medullary substance decreased, the number of mature plasma cells returned to normal in the medullary substance and decreased in the medullary sinuses.