Relative and absolute numbers of E- and EAC-rosette-forming cells in lymphoid organs.

The percentage of lymphocytes of the blood and lymphoid organs of young pigs were determined by forming rosettes with pretreated sheep red blood cells (AET-rosettes) or with sheep red blood cells coated with antibody and complement (EAC-rosettes). The mean figures for AET-rosettes were 70% for the blood, 93% for the thymus, 78% for lymph-nodes and 68% for the spleen. For EAC-rosettes the numbers were 16%, 0%, 16% and 19% respectively. The absolute numbers of rosette-forming lymphocytes were estimated on the basis of previously determined numbers of lymphoid cells in young pigs. Even by excluding the data for the thymus, there would be about three times more AET-rosette forming lymphocytes than EAC-rosette forming cells in the whole animal. About 11% of all lymphocytes did not show any of these markers. Data on the numbers of "B" and "T" lymphocytes in human lymphoid organs from the literature were summarized and compared to those found in pigs and thus, the absolute numbers for a young adult man estimated.