Characterization of tumor infiltrating NK cells (TINK) and type 1 innate lymphoid cells (ILC1) in breast cancer

SANTILLI, MARÍA CECILIA; REGGE, MARÍA VICTORIA; GANTOV, MARIANA; FRIEDRICH, ADRIÁN D.; SIERRA, JESSICA MARIEL; SECCHIARI, FLORENCIA; TROTTA, ALDANA; RUBINSZTAIN, NATALIA; LOZADA MONTANARI, BELÉN CANDELA; FUERTES, MERCEDES BEATRIZ; ZWIRNER, NORBERTO WALTER; DOMAICA, CAROLINA INÉS

Buenos Aires

Congreso; 69ª Reunión Anual de la Sociedad Argentina de Inmunología; 2021

Sociedad Argentina de Inmunología

ILC1 and NK cells are considered as innate counterparts of CD8 and Th1 CD4 T cells, respectively. They share several phenotypic and functional characteristics, and display plasticity as they can interconvert one into another in a context-dependent manner. In fact, TGF-β-driven conversion of TINK into intermediate populations of ILC1 (intILC1) and ILC1 has been proposed as a novel mechanism of tumor immune escape. However, the role of ILC1 in antitumor immunity has not been elucidated yet. Breast cancer is the most frequently diagnosed cancer and the second cause for cancer-related death in women. Thus, the aim of this work was to study TINK and ILC1 in the tumor microenvironment (TME) using the 4T1 cell mouse model of triple-negative breast cancer. BALB/c mice were injected with 30.000 4T1 tumor cells and after 19 days, mice were euthanized and cell suspensions of tumor cells, spleen, draining lymph nodes, lungs and liver were obtained to analyze the frequency and phenotype of TINK, intILC1 and ILC1 by flow cytometry. Spleens, lungs, liver and inguinal lymph nodes were also obtained from healthy mice. ILC1 and intILC1 were present in tumors and lungs, and they were absent in spleen and lymph node, while only ILC1 were found in liver from both groups of mice. A higher frequency of intILC1 than of ILC1 (p