Inhibition of tumor growth by peptide specific cytotoxic T lymphocytes in a three-dimensional collagen matrix.
Tumor associated, MHC I restricted antigenic peptides have been identified in both human and mouse tumors. Cytotoxic T lymphocytes (CTL) which recognize these tumor associated antigenic peptides are potential anti-cancer effectors. The anti-tumor activity of CTL is usually measured in vitro by the 51Cr release assay and in mice by tumor growth inhibition which is the most direct assessment of anti-tumor effect. In clinical studies, an in vivo tumor growth inhibition assay is not an option and an in vitro assay which corroborates with in vivo tumor growth is needed to assess the long-term outcome of CTL activity. Here, a three-dimensional (3-D) collagen gel assay was developed to measure in vitro the inhibition of mouse mammary tumor growth by anti-tumor CTL. BALB/c mouse CTL were induced with peptide E474 SFAVATTAL which was expressed by mouse mammary tumor cells D2F2. To measure D2F2 tumor growth inhibition in vitro, a mixture of tumor cells and anti-E474 CTL in a 1 microl cell bolus was embedded in the collagen gel. Complete eradication of tumor growth was observed at E:T ratio of or greater than 1:1. rIL-2 supplementation was necessary to achieve long-term tumor growth inhibition. Even spontaneous D2 tumor explant could be grown in the collagen gel and addition of anti-E474 to this culture reduced tumor growth. This assay system provides a realistic and sensitive alternative to the in vivo tumor growth inhibition assay and allows easy adaptation to test additional therapeutic reagents.
Wei
W Z
WZ
Karmanos Cancer Institute, Department of Immunology/Microbiology, School of Medicine, Wayne State University, Detroit, MI 48201, USA. weiw@kci.wayne.edu
Miller
B
B
Gutierrez
R M
RM
D000818:Animals; D000951:Antigens, Neoplasm / Q000276:immunology*; D003094:Collagen; D003602:Cytotoxicity, Immunologic; D007376:Interleukin-2 / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014407:Tumor Cells, Cultured
D000951:Antigens, Neoplasm; D007376:Interleukin-2; D003094:Collagen