Autopsy of the body of a 40-year-old man revealed enlarged group follicles in the small intestine. Their surface has furrows and convolutions, arranged in a pattern similar to that of a brain cortex. The follicles protrude from under the intestinal mucosa and are gray-red on section. Microscopy shows proliferation of monocytes, histiocytes, reticular cells, clusters of macrophages that form granulomas, displaced infectious disease can be characterized lymphocytes. What by these changes?