[Cytological structure of the lymph nodes after administration of foreign protein]

Changes in the cellular compositon of popliteal lymphatic nodes of albino rats were studied in normality and after injection of a foreign protein. Allergic inflammation was caused by injection of 0,25 ml of the horse serum. Observations were made on the 1, 3, 8, 19 and 30 days after the beginning of experiment. The cellular composition was counted in 30 visual fileds in the cortical plateu, follicles and myelinated cords. The average percentage of cellular elements has been determined. It has been shown that the reticular cells have less changes as compared with other cells in response to antigen stimulation. An inverse correlative relationship was noted between small and medium-sized lymphocytes. The greatest percentage of plasmic cells was noted in myelinated cords; in the follicles they are found as solitary units. In the primary immunization the cellular composition of follicles was little changed as compared with the cellular composition of the cortical and medullary substance. The cellular reaction was most pronounced in myelinated cords. Thus, the investigation of the cellular composition of different structure components of the rat's lymphatic nodes after injection of the foreign protein has revealed a different degree of their reaction.