Αn optimized, simplified and clinically approved culture system to produce, in large scale, dendritic cells capable of priming specific T cells

Abstract

Cancer immunotherapy using dendritic cells (DCs) able to induce specific immune responses to naïve T lymphocytes raises great research interest. However, the extremely complex and expensive methods used to produce DCs, combined with the limited number of autologous DCs in the circulation make any application almost impossible. Aim of the study is the development of an optimized and simplified system to easily produce in large scale cord blood-derived DCs, loaded with common tumor antigens, capable of promoting controlled Th1 immunoresponses following clinically approved maturation with vaccines. CD34+cells cultured in the presence of a cytokine cocktail in miniPERM® bioreactors and the generated DCs were matured using anti-flu vaccines. Autologous T cells plated with DCs pulsed with overlapping peptides CEA and WT1 for multiple stimulations. 200 billion of myeloid DCs were produced and matured in just 8 h in bioreactors, presenting an increased expression of the co-stimulatory molecules and also high levels of Th1 related cytokines. Upon just the 2nd stimulation, the T cells exhibited specificity following stimulation with the CEA/WT1 peptides and strong cytotoxic capacity in co-culture with a colorectal cancer (CRC)-cell line. The high produced doses of DCs, easily maturated with clinically approved agents, and capable of priming specific T cells, could potentially strengthen the further progress in DCs-mediated cancer immunotherapy field.