Renal cell carcinomas induce the up-regulation of PD-L1 on NK cells

SIERRA, JESSICA MARIEL; SECCHIARI, FLORENCIA; NÚÑEZ, SOL Y.; REGGE, MARÍA VICTORIA; FRIEDRICH, ADRIÁN D.; SANTILLI, MARÍA CECILIA; GANTOV, MARIANA; DOMAICA, CAROLINA INÉS; ZWIRNER, NORBERTO WALTER; FUERTES, MERCEDES BEATRIZ

Buenos Aires

Congreso; Reunión de Sociedades de Biociencias; 2020

Sociedad Argentina de Inmunología

Natural Killer (NK) cells are key effectors against tumor and virus-infected cells; however, evidence of a regulatory role is emerging in different models of autoimmunity and viral infections. In tumors, we have identified a subset of PD-L1-expressing tumor infiltrating NK cells in tumor-bearing mice and in patients with renal cell carcinoma (RCC). When PBMC from healthy donors (HD) were cultured with the HLA class I-/- cell line K562, PD-L1 was up-regulated on NK cells. Direct tumor recognition by NK cells and monocyte (Mo)-derived IL-18 were required for PD-L1 up-regulation. As the cellular and molecular mechanisms that control PD-L1 expression on NK cells in RCC remain unknown, the aim of this work was to study PD-L1 expression in human NK cells upon RCC recognition and the underlying mechanisms. To this end, we cultured PBMC from HD with different RCC cell lines (ACHN, SN12c and 786-O) and after 48h we evaluated PD-L1 expression on NK cells (CD56+ CD3- cells) by flow cytometry. PD-L1 was up-regulated on NK cells cultured with SN12c (p