Decreased Interferon γ Production in CD3⁺ and CD3⁻CD56⁺ Lymphocyte Subsets in Metastatic Regional Lymph Nodes of Melanoma Patients

Abstract

© 2015, Arányi Lajos Foundation. As lymphogenic dissemination is very common in melanoma, regional lymph nodes (LN)s represent first immunological barriers to tumor invasion and play a complex role in antitumor immune defense. In this sense, their most prominent role is the presentation of tumor-derived antigens to naïve T cells and generation of cell-mediated adaptive immune response. Since tumor micro-environment affects immune cell function in this study we have evaluated the ability of T cells and NK cells in metastatic (involved) and non-metastatic regional LNs to produce interferon γ (IFNγ), a pleiotropic cytokine that regulates adaptive antitumor immune response. Our results show reduced IFNγ production in both T and NK lymphocyte subsets and decreased prevalence of T cells in metastatic regional LNs of melanoma patients. The decrease of IFNγ production in T cells was more pronounced with increased number of involved regional LNs indicating tumor-induced functional impairment of both T and NK cell lymphocyte subsets in involved regional LNs. Therefore, shown low IFNγ production in metastatic LNs may represent an obstacle in adaptive cell-mediated antitumor immune response and hence may enable tumor progression.