Proliferative and cytolytic potentials of purified human tumor-infiltrating T lymphocytes. Impaired response to mitogen-driven stimulation despite T-cell receptor expression

Int J Cancer. 1988 Nov 15;42(5):659-66. doi: 10.1002/ijc.2910420504.


Using limiting dilution analysis (LDA) we have previously shown that in most instances, the frequency (F) of proliferative T lymphocyte precursors (PTL-P) was strikingly reduced in tumor-infiltrating lymphocytes (TIL). In this study involving 19 cases, we show that the impaired clonogenic potential of CD2+ TILs is primarily caused by an intrinsic defect rather than to suppressor T cells or to a direct effect of the tumor cells usually present in the culture system. This was demonstrated by experiments in which the F of PTL-Ps was quantitated both in highly purified CD2+ TILs (using a cell-sorter) and in non-purified TIL suspensions (still containing tumor cells), which originated from the same biopsy specimen. The F of PTL-Ps was virtually identical in either sorted or nonsorted suspensions and the data from LDA were always consistent with the single-hit Poisson model, indicating that no suppressor cells interfered with growth of CD2+ TIL. Stimulation of sorted CD2+ TIL in low-density cultures by either phytohemagglutinin or anti-CD3-monoclonal antibody (MAb) indicated that the antigen-dependent activation pathway was impaired, although structurally intact T-cell receptor (TCR) complexes were apparently expressed, as assessed by immunofluorescence. The depressed proliferative response of CD2+ TIL could not be reversed in vitro when phorbol-esters were used in combination with ionomycin, which bypass the TCR. Nevertheless, 180 clones obtained from 8 cases were analyzed for their cytolytic activity. The majority mediated specific lytic activity (against unknown antigens), as assessed by lectin-dependent cell cytotoxicity, whereas only 6% of them manifested lymphokine-activated killing on appropriate targets.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, Differentiation, T-Lymphocyte / analysis*
  • CD3 Complex
  • Cell Division
  • Cell Separation
  • Cell Survival
  • Ethers / pharmacology
  • Humans
  • Interleukin-2 / analysis
  • Ionomycin
  • Lymphocyte Activation
  • Receptors, Antigen, T-Cell / analysis*
  • T-Lymphocytes, Cytotoxic / immunology*
  • T-Lymphocytes, Cytotoxic / pathology
  • Tetradecanoylphorbol Acetate / pharmacology


  • Antigens, Differentiation, T-Lymphocyte
  • CD3 Complex
  • Ethers
  • Interleukin-2
  • Receptors, Antigen, T-Cell
  • Ionomycin
  • Tetradecanoylphorbol Acetate