Binding of radioiodinated bovine serum albumin to lymphoid cells of specifically primed or immunized mice in vitro

The ability of mouse popliteal lymph node cells to bind radioiodinated BSA "in vitro" was studied by radioautography. Cells of mice primed by a single injecction of 0.1 μg BSA in incoplete Freund's adjuvant bound BSA to the same extent as cells of normal mice. The increased efficiency of the secondary response cannot be therefore explained in terms of the classical clonal selection the theory Large numbers of cells from immunized nice bound the label, some of them quite strongly. Many of the labeled immune cells were of the "naked nucleus" type and only few of them were typical plasma cells.