Cellular Immunity in Cancer Patients Against Embryonal Cells

Summary

We studied by in vitro cytotoxic microassay the cellular-immune reaction of patients with different types of tumor against cells from 2 human embryos and 2 fetuses. Peripheral blood lymphocytes from 13 of 19 patients with malignant tumor and 1 of 6 patients with benign tumor showed a killing effect on 1 - to 2-month-old embryo cells, whereas no cytotoxicity was demonstrated against 4- to 5-month-old fetal cells and adult skin fibroblasts. These data suggest that patients with malignant tumor are sensitized against antigen(s) in embryo cells.