Adoptive immunotherapy for unresectable or recurrent pancreatic cancer, using lymphokine-activated killer cells or cytotoxic T cells

Abstract

Adoptive immunotherapy (AIT) has been reported to be effective for malignancies in some cases. We hypothesized that AIT may be effective for the treatment of pancreatic cancer. Seven patients with unresectable or recurrent pancreatic cancer underwent AIT, carried out with lymphokine-activated killer (LAK) cells or cytotoxic T cells (CTLS) and recombinant interleukin-2 (IL-2). The clinical and immunological effects were evaluated. Of four patients who received CTLs, one had a partial response, one had a minor response, and two showed no change. The three patients who received LAK cells had progressive disease. The CTLs had a significantly higher proportion of CD8 positive T cells and cytotoxic T cells than the LAK cells (P < 0.05), while the LAK cells had a significantly higher proportion of NK cells than did the CTLs (84 ± 12% vs 55 ± 15%,P < 0.05). The LAK activity of the CTLs (61 ± 14%) was significantly higher than that of the LAK cells (42 ± 8%,P < 0.05). Seven days after treatment with LAK cells or CTLs, lymphocyte subsets in the peripheral blood were examined. The proportion of CD8-positive T cells after CTL transfer (46 ± 5%) was greater than that before CTL transfer (28 ± 1%,P < 0.05). The proportion of cytotoxic T cells after CTL transfer increased from 23 ± 1% to 37 ± 2% (P < 0.05). However, these changes were not observed during LAK cell transfer. The proportions of suppressor inducer T cells, helper T cells, and suppressor T cells did not change during therapy. These results suggested that AIT, using CTLs, merits further clinical investigation in patients with pancreatic cancer.