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Updated: Feb 5, 2026

Efficient Transfection of In vitro Transcribed mRNA in Cultured Cells Using Peptide-Poloxamine Nanoparticles
Published on: August 17, 2022
mRNA Polyplexes with Post-Conjugated GALA Peptides Efficiently Target, Transfect, and Activate Antigen Presenting
Bo Lou1, Stefaan De Koker2, Chun Yin Jerry Lau1
1Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS) , Utrecht University , 3584CG Utrecht , The Netherlands.
Researchers developed peptide-functionalized mRNA polyplexes (PPx-GALA) for efficient delivery into antigen-presenting cells (APCs). This novel mRNA vaccine platform enhances T cell responses and DC maturation, showing promise for in vivo applications.
Area of Science:
- Biotechnology
- Immunology
- Materials Science
Background:
- Messenger RNA (mRNA) vaccines are effective for inducing CD8+ T cell responses against cancers and viral infections.
- Efficient intracellular delivery of mRNA into antigen-presenting cells (APCs) remains a challenge, requiring attachment, uptake, and endosomal escape.
Purpose of the Study:
- To develop a facile method for formulating peptide-functionalized mRNA polyplexes for enhanced antigen presentation by dendritic cells (DCs).
- To evaluate the efficacy of GALA-modified mRNA polyplexes (PPx-GALA) in cellular uptake, endosomal escape, and immune response induction.
Main Methods:
- Copper-free click chemistry was used to create peptide-functionalized mRNA polyplexes.
- Screening of membrane-active peptides (GALA, melittin, LEDE) for optimal mRNA delivery.
- Assessing transfection efficiency, cellular uptake, cytotoxicity, endosomal escape, and T cell responses in vitro.
Main Results:
- PPx-GALA polyplexes (∼350 nm, -7 mV) showed superior EGFP-mRNA transfection in macrophages and DCs compared to other peptide modifications.
- PPx-GALA demonstrated 18-fold higher cellular uptake than lipofectamine without cytotoxicity.
- Live cell imaging confirmed PPx-GALA-mediated endosomal escape and enhanced T cell responses and DC maturation when delivering OVA mRNA.
Conclusions:
- PPx-GALA represents a promising mRNA vaccine platform for efficient antigen delivery and immune stimulation.
- The formulation facilitates intracellular mRNA delivery, endosomal escape, and enhanced T cell responses.
- Further in vivo studies are warranted to validate the therapeutic potential of the PPx-GALA formulation.
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