Lymphocyte subpopulations in melanoma patients treated with dendritic cell vaccines

The main goal of cancer immunotherapy is to induce or boost tumor-specific effector cells able to eliminate or reduce tumor progression. In this study, we characterized lymphocyte phenotypes in melanoma patients receiving dendritic cell (DC)-based vaccinotherapy. We found that several biological markers served as unfavorable prognostic factors for patients' response to therapy. This included decrease of CD4+ and CD8+ lymphocyte levels, 10% and higher increase of CD16+CD3+CD8+ lymphocyte population, and increase of CD16+CD8+perforin+ T lymphocytes, especially in combination with decreased levels of CDI6+CD8(-)perforin+ and CD8+CD16(-)perforin+ cells. Increase in CD8+CD16(-)perforin+ T lymphocytes with normal levels of CD16+CD8(-)perforin+ cells and the absence of CD16+CD8+perforin+ and regulatory lymphocytes were shown to be the positive prognostic markers for patients' response to DC vaccines.