Expression of B7.1 (CD80) in a renal cell carcinoma line allows expansion of tumor-associated cytotoxic T lymphocytes in the presence of an alloresponse


  • D.J. Schendel
  • B. Frankenberger
  • P. Jantzer
  • S. Cayeux
  • E. Noessner
  • G. Willimsky
  • B. Maget
  • H. Pohla
  • T. Blankenstein


  • Gene Therapy


  • Gene Ther 7 (23): 2007-2014


  • We have selected a well-characterized human renal cell carcinoma (RCC) line as the basis for development of a genetically engineered tumor cell vaccine to be applied in an allogeneic setting. This cell line was genetically modified by retroviral transduction to express B7.1 costimulatory molecules. The unmodified tumor cells and B7.1-expressing tumor cells were compared for their ability to induce tumor-associated responses in allogeneic peripheral blood mono-nuclear cells (PBMC) of two normal control donors having single MHC class I allele matches with the tumor cells. PBMC primed using B7.1-modified tumor cells showed a preponderance of CD3+ CD8+ cytotoxic T lymphocytes (CTL) that proliferated over extended periods of time in mixed lymphocyte tumor cell (MLTC) cultures. Strong cytolytic activity developed in the primed populations and included allospecific CTL with specificity for mismatched HLA-A, -B and -C molecules. Nevertheless, it was possible to isolate CTL clones that were able to lyse tumor cells but not lymphoblastoid cells that expressed all the corresponding allospecificities. Thus, induction of complex allospecific responses did not hinder the development of tumor-associated CTL in vitro. These results support the use of this genetically modified allogeneic tumor cell line for vaccination of partial-MHC matched RCC patients.