Glycosyl-phosphatidylinositol-anchored interleukin-2 expressed on tumor-derived exosomes induces anti-tumor immune response / 中华肿瘤杂志

ABSTRACT

<p><b>OBJECTIVE</b>To prepare IL-2-anchored and tumor-derived exosomes vaccine, and investigate the antitumor efficiency of the special cytotoxic T-lymphocytes induced by Ex/GPI-IL-2.</p><p><b>METHODS</b>To construct pEGFP-N1-IL2gpi plasmid coding a fusion gene of a DNA oligo encoding GPI-anchor signal sequence attaching to human IL-2 cDNA. Then T24 cell lines stably expressing GPI-IL-2 proteins (T24/GPI-IL-2) were established. Ex/GPI-IL-2 were isolated and purified by ultrafiltration and sucrose gradient centrifugation, and the morphology and molecule markers were analyzed. The mixed lymphocyte reaction study and cytotoxic study were performed to determine the proliferative effect of T lymphocytes and the cytotoxicity induced by Ex/GPI-IL-2.</p><p><b>RESULTS</b>The pEGFP-N1-IL2gpi plasmid was successfully constructed, and cell lines stably expressing GPI-IL-2 fusion proteins were established. Ex/GPI-IL-2 were small vesicular and saucer-shaped in diameter of 30-90 nm, containing heat shock protein 70, intercellular adhesion molecule-1, MAGE-1 and GPI-IL-2. Ex/GPI-IL-2-pulsed could dendritic cells induce proliferation of T cells and cytotoxic immune response more efficiently (P<0.05).</p><p><b>CONCLUSIONS</b>GPI-IL-2 gene-modified tumor cells can make the exosomes containing GPI-IL-2 with an increased anti-tumor effect. Our study provides a feasible approach for exosome-based tumor immunotherapy of bladder transitional cell tumors.</p>