Custom Dendritic Cell Reprogramming by mRNA

Dendritic cells (DCs) play important roles in anti-tumor immune responses and reprogramming of the DCs by mRNA has shown clinical promise in recent years. Empowered by the advanced platforms and rich experience in the field of cell reprogramming and immunotherapy, Creative Biolabs leans on our in-depth studies to provide customized DCs reprogramming services by mRNA, aiming to provide a blueprint for the design and manufacture of the next generation of personalized DC-based therapies.

Introduction of DCs

At the interface between the innate and adaptive immune systems, DCs play key roles in tumor immunity and hold a hitherto unrealized potential for cancer immunotherapy. DCs are a particularly interesting immunotherapeutic target given their ability to uptake and present tumor-associated antigens (TAAs) through a variety of mechanisms: cross-presentation, cross-dressing, antigen transfer, and MHC II-restricted presentation. Currently, DCs can be exploited for vaccination against cancer through different approaches:

1. Non-targeted peptide or protein and nucleic-acid-based vaccines captured by DCs in vivo
2. Antigens targeting endogenous DCs
3. Ex vivo generated DCs matured and loaded with tumor antigens
4. Biomaterial-based platforms for the in situ recruitment and reprogramming of endogenous DCs

Fig.1 Therapeutic vaccines act via DCs to generate protective CD8+ T cell immunity. (Perez, 2019)

Genetic Reprogramming by mRNA

Although multiple clinical trials have demonstrated the safety and immunogenicity of DC vaccines, clinical responses have been largely disappointing. This can be attributed in part to functional deficiencies in the cells such as insufficient antigen presentation, migratory capacity, and cytokine release.

Reprogramming of the DCs by mRNA has emerged as a novel strategy with great promise. As an alternative to direct injection of mRNA, an immune response may also be induced by vaccination with DCs transfected with mRNA ex vivo. Scientists have successfully used RNA to program DCs. Specific functions can be achieved by transfection or co-transfection of RNAs encoding immunomodulatory molecules to induce robust and effective immune responses. Vaccination with DCs transfected with mRNA encoding tumor antigens has now been translated into clinical trials in cancer patients. Compared with other methods used for gene delivery, such as transduction with viral vectors and DNA transfection, mRNA transfection is safe, efficient and simple.

Featured DCs Reprogramming Services

By screening combinations of multiple transcription factors, Creative Biolabs has identified several transcription factors as being sufficient to reprogram DCs. Our mRNA reprogramming system contributes to a better understanding of DC specification programs and has served as a platform for the development of patient-specific DCs for immunotherapy. Transfecting DCs with mRNA that encodes immune modulating molecules (such as cytokines, chemokines, toll-like receptors, immune receptor ligands, immune receptor targeting antibodies) can program DCs behavior and/or function. An efficient method to deliver mRNA into human DCs is achieved by electroporation. The general steps are shown in Fig.2.

• Generation of in vitro transcribed mRNA with 5' cap and 3' poly(A) tail.
• Generation of human DCs.
• Programming DCs using RNA electroporation.
• FACS analysis to monitor transfection efficiency.

Fig.2 Programming human DCs with mRNA by electroporation.

RNA-based programming of DCs is a convenient, robust and clinically relevant approach to modifying DCs to develop effective cell-based therapies. If you are interested in our customized DC reprogramming services, please feel free to contact us for more information.

Reference

1. Perez, C. R.; De Palma, M. Engineering dendritic cell vaccines to improve cancer immunotherapy. Nature communications. 2019, 10(1): 1-10.