Abstract: | The immunological memory T cells assayed by the cytotoxic T lymphocyte (CTL) generation in the secondary mixed lymphocyte culture bear H-2 antigen-binding receptors as shown by the technique of the specific lymphocyte absorption on target cell (TC) monolayers of different H-2 origin. Memory T cells and specific suppressor T cells are demonstrated to be capable of adhering to native and fixed TC in a similar fashion, whereas CTL absorption appears to be two-fold reduced when the TC monolayer is fixed. The primary CTL precursors differ from memory T cells by a poor adherence to native TC which is not demonstrable at all when TC are fixed. The findings evidence the differences in receptor affinity (or structure) among the primary and secondary CTL precursors and the CTL themselves. |