title: Ex vivo identification, isolation and analysis of tumor-cytolytic T cells.
abstract: We isolated pure, viable populations of tumor-cytolytic T cells directly from patient blood samples using flow cytometric quantification of the surface mobilization of CD107a-an integral membrane protein in cytolytic granules-as a marker for degranulation after tumor stimulation. We show that tumor-cytolytic T cells are indeed elicited in patients after cancer vaccination, and that tumor reactivity is strongly correlated with efficient T-cell recognition of peptide-bearing targets. We combined CD107a mobilization with peptide-major histocompatibility complex (P-MHC) tetramer staining to directly correlate antigen specificity and cytolytic ability on a single-cell level. This showed that tumor-cytolytic T cells with high recognition efficiency represent only a minority of peptide-specific T cells elicited in patients after heteroclitic peptide vaccination. We were also able to expand these cells to high numbers ex vivo while maintaining their cytolytic potential. These techniques will be useful not only for immune monitoring of cancer vaccine trials, but also for adoptive cellular immunotherapy after ex vivo expansion. The ability to rapidly identify and isolate tumor-cytolytic T cells would be very useful in cancer immunotherapy.
authors.affiliation: Department of Medicine, Stanford University, 269 Campus Drive, Stanford, California 94305, USA.
authors.forename: Valerie
authors.initials: V
authors.lastname: Rubio
authors.forename: Tor B
authors.initials: TB
authors.lastname: Stuge
authors.forename: Naileshni
authors.initials: N
authors.lastname: Singh
authors.forename: Michael R
authors.initials: MR
authors.lastname: Betts
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Weber
authors.forename: Mario
authors.initials: M
authors.lastname: Roederer
authors.forename: Peter P
authors.initials: PP
authors.lastname: Lee
mesh_terms: D015703:Antigens, CD / Q000276:immunology; D006801:Humans; D052118:Lysosomal-Associated Membrane Protein 1; D051907:Lysosomal Membrane Proteins; D009369:Neoplasms / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000145:classification / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D052118:Lysosomal-Associated Membrane Protein 1; D051907:Lysosomal Membrane Proteins