Antitumor reactivity in vitro and in vivo of lymphocytes from normal donors and cancer patients propagated in culture with T cell growth factor (TCGF).

Peripheral blood lymphocytes (PBL) from 38 normal donors and from 27 cancer patients were propagated in bulk cultures for 3-6 weeks using T cell growth factor (TCGF). In addition, cultures derived from lymphocyte preparations enriched for or depleted of natural killer (NK) cells and several clones of cultured cells were studied. The following main observations were made: (a) PBL of both patients and healthy donors could be expanded to large numbers (up to 2500-fold); (b) CLC derived from unfractionated PBL exhibited intermediate levels of cytotoxic activity against autologous and allogeneic fresh lung tumor cells and strong cytotoxicity toward several cultured adherent tumor cells; (c) whereas cultures originated from populations enriched for NK cells were highly cytotoxic against both adherent tumor target cells and against an NK-sensitive leukemic cell line (K562), cultures derived from populations depleted of NK cells were preferentially cytotoxic to adherent target cells; (d) clones of CLC were also strongly cytotoxic, but 2 out of 3 clones tested showed a narrower spectrum of target cytotoxicity than that of uncloned CLC; (e) CLC, when mixed with two carcinoma cell lines, were able to inhibit tumor growth in nude mice.