Cell surface phenotypes of radiolabeled immune long-lived lymphocytes that selectively localize in syngeneic tumours

Using a cell separation technique to isolate mononuclear leukocytes from solid tumors in conjunction with combined radioautography and two-color immunofluorescence, we have characterized the surface markers of 3H-labeled, immune, long-lived, small lymphocytes (LLSLs) that selectively localize into chemically induced sarcomas. When small tumor pieces were implanted into immune mice whose LLSLs had been radiolabeled, the LLSLs that selectively localized into those tumors to which the hosts had been immunized were predominantly Thy-1+, Lyt-1+2-. Localization into the appropriate tumor was also detected upon adoptive transfer of immune LLSLs to tumor-bearing mice, especially when these mice had, before transfer, received 400 rads of whole-body irradiation. These 3H-labeled LLSLs were also found to be predominantly Thy-1+, Lyt-1+2-.