Study on the Effect of High Expression of Linker for Activated T Cells in Nude Mice Tumor Model

Author(s): ZHANG Min-Rui, Gao Mei-Hua, MA Yu, WANG Bing, ZHANG Bei

BACKGROUND: The activation and proliferation of T cells are based on the signal transduction after combinating of ligands and T cell antigen receptors(TCRs). As an adapter molecular, LAT(Linker for Activation of T Cells) is a kind of transmembrane protein which leads to a positive regulation for growth and differentiation of T cells[1,2]. Then, the palmitoylation of LAT is the foundation of signal transduction process. OBJECTIVE: By construct an tumor model with T leukemia Jurkat cells in nude mice, to research the effect of high expression of LAT to tumor load of mice. METHODS: Culturing the Jurkat cell line, the 5 weeks old female node mice were classified to three groups: high expression of LAT group, LAT mutation group and normal Jurkat group, each group had 8 mice. After pretreated with cyclophosphamide, 5×106/mice Jurkat cells were injected at armpit. Then observed the tumor of mice, measured weight of tumors, and HE stained of tumor tissues. Flow cytometry was used to detect proliferation of tumor cell in peripheral blood. ELISA was used to test the level of interleukia (IL)-2 in serum. RESULTS: After injected cells several days, the nude mice have appeared tumors under armpit and some symptoms like somnolent, anorectic and ect. The results of Flow cytometry and ELISA had shown that high expression of LAT group had the highest rate of tumor cells proliferation than other groups. CONCLUSION: It was successfully established the nude tumor model of T lymphocyte, confirmed the positive effect of LAT to the T cells activation and proliferation, provided a new target for acute T lymphocytic leukemia gene therapy.

LAT, Nude, Tumor Model, Leukemia

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