A Quantitative Study of the Plasma Cell Population in Lymphoid Organs of Young Adult Albino Rats

Abstract

1. The percentage of plasma cells in total nucleated cells was determined with smear and imprint preparations of various lymph nodes, spleen, thymus, and PEYER's patches of normal albino rats. Plasma cells were found consistently in all the lymphoid organs examined, but their percentage was relatively high in all the lymph nodes except the superficial inguinal lymph nodes and also in the spleen, and remarkably low in the thymus or PEYER's patch, The organs mentioned in the order of decreasing percentage of plasma cells are: mesenteric lymph node (2.51±0.38%), superficial cervical lymph nodes (1.59±0.16%), deep cervical lymph nodes (1.53±0.41%), iliac lymph nodes (1.46±0.17%), popliteal lymph nodes (0.80±0.37%), spleen (0.75±0.14%), superficial axillary lymph nodes (0.64±0.24%), deep axillary lymph nodes (0.41±0.37%), superficial inguinal lymph nodes (0.27±0.09%), PEYER's patches (0.21±0.05%) and thymus (0.19±0.05%).2. A fairly remarkable regional difference was noticed in the percentage of the plasma cells in lymph nodes. Among lymph nodes of the same region, secondary lymph nodes tended to show higher percentage of plasma cells than primary ones in the lower half of the body, but such a trend could not be found in the upper half of the body.3. There was a fairly considerable individual variation in the percentage of the plasma cells in lymphoid organs, the variation coefficient of the organs except for the superficial, iliac, and mesenteric lymph nodes as well as the spleen being more than 50per cent.4. There was a trend of higher percentage of plasma cells being generally accompanied by a higher percentage of the granulocytes.