Interactions between T-reg and NK lymphocytes from patients with ovarian neoplasia

• Grant number: 14/17444-1
• Support type: Regular Research Grants
• Duration: January 01, 2015 - March 31, 2017
• Field of knowledge: Biological Sciences - Immunology - Cellular Immunology
• Principal researcher: Fernando Guimarães
• Grantee: Fernando Guimarães
• Home Institution: Centro de Atenção Integral à Saúde da Mulher (CAISM). Hospital da Mulher Professor Doutor José Aristodemo Pinotti. Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Assoc. researchers: Daniela Maira Cardozo ; Sophie Françoise Mauricette Derchain

Abstract

The natural killer (NK) cells are cytotoxic lymphocytes that act innately in defending the body against viral infections and neoplasms. Recently, we have demonstrated that it is possible to obtain enriched NK cell preparations from patients with ovarian cancer by long-term in vitro culture of peripheral blood mononuclear cells (PBMC). The effector cells thus obtained possess significantly greater proportion of functional NK cells than the usual preparations LAK cells (lymphokine activated killer). Additionally, we observed a significant increase in the expression of various activating receptors on NK cells, including the DNAM-1 receptor, which often is reduced in NK cells from patients with malignant ovarian neoplasm. However, preliminary data indicate that the expansion of effector cells from patients with ovarian cancer is eventually, accompanied by the growth of the population of regulatory T lymphocytes (T-reg). The T-reg lymphocytes have been implicated in the mechanisms of suppression of the immune response against tumors, including ovarian cancer. In general, the presence of T-reg cells in tumor lymphocytic infiltrate, as well as the production of TGF-² cytokines IL-10, are associated with worse prognosis. However, it is not known the specific mechanisms by which T-reg lymphocytes influence the function of NK cells. Thus, this study aims to evaluate the interaction between NK and T-reg of patients with ovarian cancer lymphocytes, elucidating the possible mechanisms of modulation of effector function of NK cells. (AU)