Marked differences in human melanoma antigen-specific T cell responsiveness after vaccination using a functional microarray.
BACKGROUND
In contrast to many animal model studies, immunotherapeutic trials in humans suffering from cancer invariably result in a broad range of outcomes, from long-lasting remissions to no discernable effect.


RESULTS
In order to study the T cell responses in patients undergoing a melanoma-associated peptide vaccine trial, we have developed a high-throughput method using arrays of peptide-major histocompatibility complexes (pMHC) together with antibodies against secreted factors. T cells were specifically immobilized and activated by binding to particular pMHCs. The antibodies, spotted together with the pMHC, specifically capture cytokines secreted by the T cells. This technique allows rapid, simultaneous isolation and multiparametric functional characterization of antigen-specific T cells present in clinical samples. Analysis of CD8+ lymphocytes from ten melanoma patients after peptide vaccination revealed a diverse set of patient- and antigen-specific profiles of cytokine secretion, indicating surprising differences in their responsiveness. Four out of four patients who showed moderate or greater secretion of both interferon-gamma (IFNgamma) and tumor necrosis factor-alpha (TNFalpha) in response to a gp100 antigen remained free of melanoma recurrence, whereas only two of six patients who showed discordant secretion of IFNgamma and TNFalpha did so.


CONCLUSIONS
Such multiparametric analysis of T cell antigen specificity and function provides a valuable tool with which to dissect the molecular underpinnings of immune responsiveness and how this information correlates with clinical outcome.
Chen
Daniel S
DS
Department of Internal Medicine/Division of Oncology, Stanford University, Stanford, California, United States of America.
Soen
Yoav
Y
Stuge
Tor B
TB
Lee
Peter P
PP
Weber
Jeffrey S
JS
Brown
Patrick O
PO
Davis
Mark M
MM
D000917:Antibody Formation; D000951:Antigens, Neoplasm / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D019496:Cancer Vaccines / Q000276:immunology*; D016207:Cytokines / Q000378:metabolism; D006801:Humans; D008545:Melanoma / Q000276:immunology* / Q000628:therapy; D040081:Protein Array Analysis
D000951:Antigens, Neoplasm; D019496:Cancer Vaccines; D016207:Cytokines