Small extracellular vesicles from pancreatic ductal adenocarcinoma cells modulate natural killer cells activity

DANIELA L. PAPADEMETRIO; MARIA NOÉ GARCIA; SANTIAGO BEHR; MARIEL BENITEZ; DANIEL GRASSO; ELIDA ALVAREZ

Mar del Plata

Congreso; Reunión Anual de Biociencias 2022; 2022

Sociedad Argentina de Investigación Clínica

Pancreatic ductal adenocarcinoma (PDAC) induces immunotolerance where tumor-derived extracellular vesicles (EVs) play a crucial role bearing signaling mediators from tumor to immune cells. Despite its poor efficacy, Gemcitabine (G) is a first line agent for PDAC treatment. Type-I IFNs had been shown to possess antitumoral properties with a model-dependent behavior. We investigated the role of G, IFNα and IFNβ in tumor derived small EVs composition and their impact on NK cells activity. Small EVs were collected from supernatants of MIAPaCa-2 and PANC-1 cells upon 2h of G or IFNs treatments. NK cells from Buffy-Coats of healthy donors were purified by magnetic MAbs negative selection. NK cytotoxicity was evaluated by CFSE/PI stain on K562 cells. We incubated NK cells with EVs for 2h. CFSE dyed-K562 cells were added in ratio 5:1 (NK:K562) for 4h. IFNγ release was measured in supernatants from cytotoxicity assays by ELISA. CD107a was analyzed in NK cells by flow cytometry. EVs-G slightly increased NK cytotoxicity (19% and 21%, for MIAPaCa-2 and PANC-1, respectively (p