AUTOPHAGY ALTERS THE COMPOSITION OF PANCREARTIC EXOSOMES AND MODULATES THE ANTITUMORAL ACTIVITY OF NK CELLS

ESTEFANIA S. PAPARATTO; NADIA PAGLILLIA; MARIA NOÉ GARCIA; DANIEL GRASSO; ELIDA ALVAREZ; DANIELA L. PAPADEMETRIO

Tucumán

Congreso; LXVII Reunión Científica Anual de la Sociedad Argentina de Inmunología; 2019

Sociedad Argentina de Inmunología

Pancreatic ductal adenocarcinoma (PDAC) induces immunotolerance where exosomes are intercellular messengers, carrying molecules from tumor to immune cells. We previously described that autophagy is crucial for PDAC survival to gemcitabine. We investigated the role of autophagy in tumor-derived exosomes composition and their impact on Natural Killer cells (NK) activity. Exosomes were collected from supernatants of MIAPaCa-2 (EXOM-Basal) and PANC-1 (EXOP-Basal) treated with gemcitabine (Gem), Spautin-1 (SP-1) as autophagy inhibitor and starvation (St) as autophagy inducer during 2h. NK cells from Buffy-Coats of healthy donors (Ethical statement CEIC-Res#677-19) were purified by magnetic MAbs negative selection. NK cytotoxicity was evaluated by CFSE/PI stain on K562 cells. We incubated NK cells with EXOM/P-Basal, EXOM/P-Gem, EXOM/P-SP-1 or EXOM/P-St during 2h. CFSE dyed-K562 cells were added in ratio 5:1 (NK:K562) for 4h. IFNγ release was evaluated in supernatants of cytotoxicity assays by ELISA. CD107a expression was evaluated in co-cultures of NK:K562 ratio 1:1.EXOM-Gem increased NK cytotoxicity in 19% (p