Mechanism of lymphocyte function-associated antigen-l/intercellular adhesion molecule-1 mediatedanti-neoplastic effects of cytokine-induced killer cells

Abstract

Objective To investigate the molecular mechanism underlying lymphocyte function- associated antigen-1 （LFA-1） / intercellular adhesion molecule-1 （ICAM-1） mediated anti-neoplastic effects of cytokine induced killer （CIK） cells. Methods Lymphocytes isolated from peripheral blood of children leukemia were induced with interferon-gamma （IFN-20, anti-CD3monoclonal antibody （CD3McAb） and interleukin-2 （IL-2） and co-cultured with dendrite cells （DC） to generate DC-CIK cells. When treated with LFA-1 monoclonal antibody, cytotoxicity of DC-CIK cells against leukemia cell lines was measured by the MTT assay, while RT-PCR and Western blotting were used to determine mRNA and protein expressions of GATA-3 and T-bet in DC-CIK cells, respectively. IL-12, IFN-γ and tumor necrosis factor-α （TNF-α levels released by DC-CIK cells were quantified by ELISA. Results Induced DC-CIK cells were regular, round and transparent with variable cell volume and cellular aggregation. When treated with mouse anti-human LFA-1 monoclonal antibody, the cytotoxicity decreased mostly towards B95 cells under administration of 20 μg/ml LFA-1 monoclonal antibody in comparison with the control group（t =10. 138, P 〈0.05）. It led to a highest elevation of GATA-3 mRNA and protein levels （t =16.386, P 〈 0.05; t =22.652, P 〈 0.05） and a most decrease of T-bet mRNA and protein levels （t =17.728, P 〈0.05; t =17.452, P 〈0.05） under 20 p,g/ml LFA-1 monoclonal antibody in B95 cells group in comparison with the control grouP. The expression levels of IL-12, IFN-T, and TNF-α in supernatant were the lowest under 20 μg/ml LFA-i monoclonal antibody in B95 cells group in comparison with the control group （t =21.621, P 〈0.05; t =13.739, P 〈0.05; t =15.278, P 〈0.05）. Conclusion GATA-3 and T-bet were implicated in the LFA-1/ICAM-1 mediated anti-neoplastic effects of DC-CIK cells via activation of the Thl pathway, with high secretion of Thl cytokines, such as IL-12, IFN-γ and TNF-α. Key words: Lymphocyte function-associated antigen-I; Intercellular adhesion molecule-l; DC-CIK; GATA3 transcription factor; T-bet gene