Comparative study of various subpopulations of cytotoxic cells in blood and ascites from patients with ovarian carcinoma
Abstract
A number of observations indicate that the immune system plays a significant role in patients with epithelial ovarian cancer (EOC). In case of EOC the prognostic significance of tumour infiltrating lymphocytes, (TILs) has not been obviously explained yet.
The aim is to determine the phenotype and activation molecule of cytotoxic T cells and NK cells subpopulations and to compare their representation in malignant ascites and peripheral blood (PBL) in patients with ovarian cancer. The cytotoxic cells taken from blood samples of the cubital vein and malignant ascites were obtained from 53 patients with EOC.
Their surface and activation characteristics were determined by means of a flow cytometer. Immunophenotype multiparametric analysis of PBL and TILs was carried out.
CD3+ T lymphocytes were the main population of TILs (75.9%) and PBL (70.9%). The number of activating T cells was significantly higher in TILs, CD3+/69+ 6.7% vs.0.8% (p<0.001).
The representation of (CD3-/16+56+) NK cells in TILs was significantly higher, 11.0% vs. 5.6% (p=0.041), alike CD56bright and CD56bright from CD56+ cells were higher in TILs (both p<0.001). The activation receptor NKG2D was present on 45.1% of TILs vs. 32.3% of PBLs (p=0,034), but in the numbers of CD56+/NKG2D+ in TILs and PBLs we did not find significance.
The above-mentioned results prove that the characteristics and intensity of anti-tumour responses are different in compared compartments (ascites/PBL). The knowledge of phenotype and functions of effector cells, which are responsible for the anti-tumour response, are the basic precondition for understanding the anti-tumour immune response and the cause of its failure.