Activation of cytotoxic response mediated by polyfunctional natural killer cells and t CD8+ cells induced by Toll-like-receptors agonists in the mycosis fungoides and Sézary syndrome

Abstract

The most frequent form of cutaneous T cell lymphoma (CTCL), non-Hodgkin's type, is the Mycosis Fungóides (MF) and Sézary Syndrome (SS). In the early stages of CTCL there is a predominant regulatory profile in skin lesions and with disease progression there is a predominance of CD4+ Th2 cells. In parallel, due to tumor escape mechanisms, occurs a declining in the activity of effectors CD8+ T cells and Natural Killer (NK) cells, which are crucial components for antitumor response and controlling of disease progression. The use of innate immunity adjuvants such as Toll-like ligands, mainly those intracellular receptors, has been exploited to potentiate antitumor immunity. The aim of the study is to analyze in mycosis fungoides/Sézary Syndrome the responsiveness of NK cell subtypes and polyfunctional CD8+ T cells to the agonists of Toll-like receptors (TLR) and ligand for STING (stimulator genes for type I IFN). The frequency of regulatory T cells (Foxp3+) will be evaluated. In the mononuclear cells (MNC) from peripheral blood of patients with MF/SS. Therefore, the production of TNF-a, IFN-g, IL-10 and IL-17 by MNC upon TLR 2/7, 7/8 and STING (3', 3'- cGAMP) activation will be assessed. The frequency of NK cells subtypes which express inhibitory receptor (CD94-NKG2A) or activating (NKG2D) and natural cytotoxicity receptors, such as NKp30 and NKp46 as well as CD8+ T cells expressing IFN-g, TNF-±, CD107a will be analyzed upon stimulation with TLR2/7, TLR7/8 and STING ligands. The profile of memory NK cells will also be evaluated in MNCs. The frequency of regulatory T cells (CD3+, CD4+, CD25+, CD45RA, CD127-, CD95, Foxp3+) will be evaluate in non-malignant cells and malignant cells phenotype (CD3+,CD4+, CD5+, CD8-, CD7-,CD26-,CD158k, NKp46, Foxp3+) in the SS cases. The mRNA expression of NK receptor ligands and inhibitory molecules will be analyzed in skin lesions in plaque or tumor stages. The analysis of effect/cytotoxic and regulatory potential is crucial for better understanding the immunopathogenesis and to verify the potential modulator adjuvants as a strategy to enhance the antitumor response in CTCL. (AU)