Functional integrity of NK and NK-like T lymphocytes from ovarian neoplasia patients

Author(s)

Rodrigo Fernandes da Silva

• Document type: Master's Dissertation
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Ciências Médicas
• Defense date: 2013-07-26

Examining board members

Carlos Alberto Petta; Joana Froes Bragança Bastos; Márcia Antoniazi Michelin

• Advisor: Carlos Alberto Petta; Fernando Guimarães

Abstract

NK cells are lymphocytes known by their ability to eliminate a variety of malignant cells without previous stimulation, in a process involving innate recognition by an array of stimulatory and inhibitory receptors. Similarly, the variant subset of NK-like T lymphocytes has been reported to eliminate tumor cells, but the targeting process might involve either innate or adaptive immune recognition. This study evaluated the functional activation of NK and NK-like T cells, the expression of activating receptors DNAM-1, NKp30 and NKp44 (pre, short- and long-term IL-2 stimulated), from blood and ascites of ovarian neoplasia patients. Blood was collected from 24 patients with ovarian neoplasias after signed consent: 11 benign (Bng), 6 malignant without metastasis (Mlg) and 7 malignant with metastasis (MlgMt). Ascites (Asc) was collected from 6 patients with ovarian neoplasia. Mononuclear cells were separated by gradient centrifugation. NK and NK-like T cells activation (pre, short- and long-term stimulated) was evaluated against K562 (1:1 ratio) by the expression of CD107a, analyzed by flow cytometry. Short-term stimulation with IL-2 (1000UI/ml) was conducted overnight in RPMI-1640 medium supplemented with FBS (10%) and L-glutamine (2mM). Long-term stimulation was conducted by a 21 day culturing process with SCGM CellGro medium supplemented with anti-CD3 (10ng/ml, first 5 days), IL-2 (1000UI/ml) and FBS (10%). The functional activation of NK cells pre stimulated seemed to be impaired with the progression of the disease. Short-term stimulation increased NK cells activation, but not significantly. Long-term stimulation increased NK cells activation significantly (p<0.001). The percentage of NK cells expressing the activating receptors DNAM-1, NKp30 and NKp44 increased significantly (p<0.05) after long-term stimulation. NK-like T cells showed low activation on pre and short-term and none activation on long-term IL-2 stimulation. Long-term stimulation resulted in a much higher number of functional NK cells compared to short-term, entitling this method for adoptive therapy. Long-term stimulation was particularly efficient to up-regulate DNAM-1 activating receptor on NK cells, representing a way to overcome down-regulation demonstrated on patients with ovarian carcinoma. The lack of activation of NK-like T cells (pre, short- and long-term IL-2 stimulated) suggests that, in the method applied; these cells are not activated through innate pathway (AU)

• FAPESP's process: 10/17202-7 - Autologous antitumor activity of NK cells expanded in vitro from ovarian cancer patients
• Grantee: Rodrigo Fernandes da Silva
• Support Opportunities: Scholarships in Brazil - Master