Human Lymphocyte Subpopulations in Metastatic Neoplasia — Six Years Later

IN 1977, Yu and associates reported the existence of an inhibitory T lymphocyte in patients with osteogenic sarcoma. This cell type suppressed in vitro tumor-specific cytotoxicity mediated by non-T, non-B, non-monocyte effector cells from the same patients.1 The authors posed two provocative questions based on their finding that three of the four patients in whom suppressor cells were detected had pulmonary metastases at the time: Does the production of inhibitory lymphocytes play a part in oncogenesis? and, Would it be reasonable to treat patients with agents that selectively reduce the numbers of circulating suppressor T cells?In our accompanying editorial, . . .