Repolarization of human M2 macrophages restores NK cell-mediated functions: implications in human renal cell carcinomas.

NÚÑEZ, SOL YANEL; SIERRA, JESSICA MARIEL; SECCHIARI, FLORENCIA; REGGE, MARÍA VICTORIA; ZIBLAT, ANDREA; FRIEDRICH, ADRIÁN; DOMAICA, CAROLINA INÉS; FUERTES, MERCEDES BEATRIZ; ZWIRNER, NORBERTO WALTER

Congreso; Reunión anual de la Sociedad Argentina de Inmunología; 2018

SAIC-SAI-SAFIS

Macrophages represent the most abundant population within the tumor microenvironment and they have been associated with poor prognosis in many cancer patients due to local and systemic effects that facilitate tumor growth, aberrant angiogenesis, metastases and immunosuppression. We previously demonstrated that anti-inflammatory macrophages (M2) inhibit NK cell-mediated cytotoxicity against tumor cells and IFN- production upon stimulation with cytokines. Also, we demonstrated that M2-driven up-regulated expression of the inhibitory receptor CD85j (ILT-2) on NK cells restrains NK cell degranulation through interaction with HLA-G expressed by M2. Therefore, in this work we characterized the macrophage polarization status and the expression of CD85j in NK cells from human renal cell carcinoma (RCC) biopsies. Flow cytometry analysis revealed a higher percentage of CD68+ (macrophages) infiltrating cells within tumors compared with renal healthy parenchyma (HP) (p