Artificial antigen-presenting cells transduced with telomerase efficiently expand epitope-specific, human leukocyte antigen-restricted cytotoxic T cells

Cancer Res. 2005 Jun 15;65(12):5417-27. doi: 10.1158/0008-5472.CAN-04-2991.

Abstract

Human telomerase reverse transcriptase (hTERT) is overexpressed in most human tumors, making it a potential target for cancer immunotherapy. hTERT-derived CTL epitopes have been identified previously, including p865 (RLVDDFLLV) and p540 (ILAKFLHWL), which are restricted by the human leukocyte antigen (HLA) class I A*0201 allele. However, it remains a major challenge to efficiently and consistently expand hTERT-specific CTLs from donor peripheral blood T lymphocytes. To bypass the need for generating conventional antigen-presenting cells (APC) on an autologous basis, we investigated the potential ability of fibroblast-derived artificial APCs (AAPC) to activate and expand HLA-A*0201-restricted CTLs. We show here that AAPCs stably expressing HLA-A*0201, human beta(2)-microglobulin, B7.1, intercellular adhesion molecule-1, and LFA-3, together with either p540 and p865 minigenes or the full-length hTERT, effectively stimulate tumoricidal, hTERT-specific CTLs. hTERT-expressing AAPCs stimulated both p540 and p865 CTLs as shown by peptide-specific cytolysis and tetramer staining, indicating that hTERT is processed by the AAPCs and that the two peptides are presented as codominant epitopes. The level of cytotoxic activity against a panel of tumors comprising hematologic and epithelial malignancies varied, correlating overall with the level of HLA-A2 and hTERT expression by the target cell. Starting from 100 mL blood, approximately 100 million hTERT-specific CTLs could be generated over the course of five sequential stimulations, representing an expansion of approximately 1 x 10(5). Our data show that AAPCs process hTERT antigen and efficiently stimulate hTERT-specific CTLs from human peripheral blood T lymphocytes and suggest that sufficient expansion could be achieved to be clinically useful for adoptive cell therapy.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antigen-Presenting Cells / immunology*
  • Cell Line, Tumor
  • DNA-Binding Proteins
  • Epitopes, T-Lymphocyte / biosynthesis
  • Epitopes, T-Lymphocyte / genetics
  • Epitopes, T-Lymphocyte / immunology*
  • HLA-A Antigens / genetics
  • HLA-A Antigens / immunology
  • HLA-A2 Antigen
  • Humans
  • Immunotherapy, Adoptive / methods*
  • K562 Cells
  • Lymphocyte Activation
  • Mice
  • Molecular Sequence Data
  • Peptide Fragments / genetics
  • Peptide Fragments / immunology
  • T-Lymphocytes, Cytotoxic / immunology*
  • Telomerase / genetics
  • Telomerase / immunology*
  • Telomerase / metabolism
  • Transduction, Genetic
  • Transfection

Substances

  • DNA-Binding Proteins
  • Epitopes, T-Lymphocyte
  • HLA-A Antigens
  • HLA-A*02:01 antigen
  • HLA-A2 Antigen
  • Peptide Fragments
  • Telomerase