Closing the system: production of viral antigen-presenting dendritic cells eliciting specific CD8+ T cell activation in fluorinated ethylene propylene cell culture bags

Abstract

Background A major obstacle to anti-viral and -tumor cell vaccination and T cell immunotherapy is the ability to produce dendritic cells (DCs) in a suitable clinical setting. It is imperative to develop closed cell culture systems to accelerate the translation of promising DC-based cell therapy products to the clinic. The objective of this study was to investigate whether viral antigen-loaded monocyte-derived DCs (Mo-DCs) capable of eliciting specific T cell activation can be manufactured in fluorinated ethylene propylene (FEP) bags. Methods Mo-DCs were generated through a protocol applying cytokine cocktails combined with lipopolysaccharide or with a CMV viral peptide antigen in conventional tissue culture polystyrene (TCPS) or FEP culture vessels. Research-scale (< 10 mL) FEP bags were implemented to increase R&D throughput. DC surface marker profiles, cytokine production, and ability to activate antigen-specific cytotoxic T cells were characterized. Results Monocyte differentiation into Mo-DCs led to the loss of CD14 expression with concomitant upregulation of CD80, CD83 and CD86. Significantly increased levels of IL-10 and IL-12 were observed after maturation on day 9. Antigen-pulsed Mo-DCs activated antigen-responsive CD8+ cytotoxic T cells. No significant differences in surface marker expression or tetramer-specific T cell activating potency of Mo-DCs were observed between TCPS and FEP culture vessels. Conclusions Our findings demonstrate that viral antigen-loaded Mo-DCs produced in downscaled FEP bags can elicit specific T cell responses. In view of the dire clinical need for closed system DC manufacturing, FEP bags represent an attractive option to accelerate the translation of promising emerging DC-based immunotherapies.

Optimization and Validation of a Harmonized Protocol for Generating Therapeutic-Grade Dendritic Cells in a Randomized Phase II Clinical Trial, Using Two Varied Antigenic Sources

“…Several culture vessels have been evaluated for their suitability to generate large-scale DCs with materials like polystyrene (culture flasks), polyolefin (bags), and FEP (bags) [ 26 , 27 ]. Such studies showed that cell culture bags like the FEP-based VueLife A/C, which had a higher surface energy, were ideal, as they could easily accommodate clinical-scale volumes of starting and in-process material and were superior to flask-cultured cells in terms of yield, viability, and function with a reduced risk of contamination [ 28 , 29 ]. Our own results showed that a closed FEP-based system had the advantage of twin surface adherence for monocyte enrichment.…”

Nano Drug Delivery System for Tumor Immunotherapy: Next-Generation Therapeutics

“…In 2010, the FDA approved sipuleucel-T (Provenge) for the treatment of advanced prostate cancer. Provenge was hence the first autologous active immunotherapy drug and the first true therapeutic cancer vaccine ( 68 ).…”

Adoptive Immunotherapy beyond CAR T-Cells

“…Single-use bag bioreactors are somewhat similar to the conventional flasks, with the advantage of accurate and sterile medium supply, as well as enhanced sterility during cell growth and various manipulations. Simplicity of the device allows it to be used with the majority of cellular products, e.g., DCs, Tregs, CAR T-cells, TILs [95,96].…”

“…Single-use bag bioreactors are somewhat similar to the conventional flasks, with the advantage of accurate and sterile medium supply, as well as enhanced sterility during cell growth and various manipulations. Simplicity of the device allows it to be used with the majority of cellular products, e.g., DCs, Tregs, CAR T-cells, TILs [95,96]. The most common bioreactors for growing immune cells are suspension-based, such as the G-Rex ® flask by Wilson Wolf Inc. (New Brighton, MN, USA) and Z ® RP cell cultivation platform by Zellwerk GmbH (Oberkrämer, Germany).…”