Expression of LTβR-Ig fusion protein by eukaryocytes and evaluation of its bioactivity in vitro

Objective To express recombinant murine LTβR-Ig in CHO cells and evaluate its activities in suppressing T cell proliferation in vitro.Methods Insert LTβR outer domain cDNA and human IgG1 Fc cDNA into the expression vector pcDNA3.1(+),then transfect CHO-K cell line.Using Sepharose-protein A affinity column to purify the recombinant protein,and using 3[H]TdR incorporation method to measure T cell proliferation.Results The recombinant vector,LTβR-Ig/pcDNA3.1(+) was constructed and verified by PCR amplification,restriction endonucleases digestion and following sequencing.LTβR-Ig recombinant protein was stably and consistently expressed in CHO cells and the purified protein can effectively suppression T cell proliferation.Conclusion LTβR-Ig recombinant protein with biological activity was expressed in the eukaryotic system.It will provide a clue for study of LTβR in transplant rejection and develop a method by using recombinant gene drugs to treat diseases.