Enhanced anti-tumor immunity generated by Rituximab-coated tumor cell vaccine.

Rituximab is a chimeric monoclonal antibody against CD20, and has been used to treat malignant tumors derived from B cell. We designed a tumor cell vaccine modified by Rituximab, and evaluated anti-tumor effect in human CD20 gene transfected mice tumor model in vivo, and in human CTLs induction by mixed lymphocyte tumor cell culture in vitro. The results demonstrated that the Rituximab-coated tumor cell vaccine had a significant therapeutic effect against tumor pulmonary metastasis formation. Antibody depletion experiments showed CD8+ T Cells were essential for the anti-tumor effect but not NK cells. Capture rate of tumor cells by DCs, which were detected by flow cytometry, was increased by adding Rituximab. The tumor specific cytolysis could be induced by Rituximab-coated tumor cell in human in vitro assay. This therapeutic strategy provides a simple way to potentialize CTLs function to combat cancer and may promote more clinical consideration in immunotherapy for tumors. Rituximab-coated tumor cell vaccine also expanded the clinical Rituximab applications.