ラット皮膚細胞に対する natural cytotoxicity (SCMC) の検討―natural cytotoxicity 細胞(NC)とキラー細胞(KC)との比較

We have reported that normal rat spleen cells show spontaneous cell-mediated cytotoxicity (SCMC) against rat skin epidermal cells and that the cold target inhibition assay reveals that NC and immune spleen cells belonged to different cell populations. This time, we attempted to separate NC and KC from skin allografted immune spleen cells by using Percoll sedimentation and compare their cytotoxicity with that of normal spleen cells. Normal and skin grafted immune spleen cells were fractionated by 30-50% (grading by 5%) Percoll, and each fraction was used as an effector in the (51)Cr release cytotoxicity assay with the target of allogeneic or syngeneic rat tail epidermal cells. The results were; Fr. 40% as NC and Fr. 50% as KC population. Cytotoxicity of nonadherent cells to the plastic dish and nylon wool column showed approximately the same distribution. Cold target inhibition assay was then performed with each fraction, confirming the results in our previous report. Each fraction was treated with antiasialo GM1 serum and complement and drastic elimination of the cytotoxicity was seen only in Fr. 40%. In addition, cytotoxicity of Fr. 40% and Fr. 50% of 0, 1, 2, 3, 4, 7, 10, 13 and 16th days, following the syngeneic and allogeneic skin graft, was mointored in order to determine the kinetics of NC and KC activities.