Distribution pattern of lymphocyte subpopulations in human tonsils as analysed by monoclonal antibodies with double immunoenzymatic labeling.

The distribution of B- and T-lymphocytes, T-cell subpopulations, including natural killer cells and monocytes/macrophages, was studied in cryostat sections of human tonsils by the avidin-biotin-peroxidase technique using monoclonal antibodies. A double immunostaining procedure was also developed to detect two types of lymphocytes on one single section simultaneously using horseradish peroxidase and alkaline phosphatase as labeling enzymes. The primary follicles and the germinal centers of the secondary follicles were mainly found to be positive for B-cells. T-cells were predominantly localized in the follicular caps and in the interfollicular areas. The ratio of helper/inducer cells to suppressor/cytotoxic cells was in favour of helper T-cells. Both subpopulations were also predominant in follicular caps and interfollicular areas. The quantity of natural killer cells was very variable and nearly all were localized exclusively in the germinal centers. Monocytes/macrophages were only seen occasionally in the interfollicular areas. The double-immunoenzymatic labeling was useful for the visualization of combinations of antigens, however, without demonstrating the presence of two different surface antigens on one single cell.