Investigating the delivery of PD-L1-targeted immunoliposomes in a dynamic cervical cancer-on-a-chip model
Seth-Frerich Fobian1, Mohamadreza Amin2, Andrea Sacchetti3
1Precision Medicine in Oncology (PrMiO), and Nanomedicine Innovation Center Erasmus (NICE), Department of Pathology, Erasmus MC Cancer Institute, Erasmus MC, Dr. Molewaterplein 40, 3015 GD Rotterdam, the Netherlands; Department of Radiation Oncology, Amsterdam UMC, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands; Center for Experimental and Molecular Medicine (CEMM), Laboratory for Experimental Oncology and Radiobiology (LEXOR), Cancer Center Amsterdam (CCA), Amsterdam UMC, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands.
Abstract:
The recent approval of pembrolizumab in recurrent or metastatic cervical cancer warrants further investigations into the usefulness of immunotherapies for more durable and less radical interventions. In this study, the targeting potential of anti-PD-L1-functionalized immunoliposomes was tested in a 3D in vitro cervical cancer-on-a-chip model. Immunolipsomes were synthesized and decorated externally with monovalent anti-PD-L1 Fab' fragments of commercially available atezolizumab. Cervical cancer cell lines with varying levels of PD-L1 expression were cultured as spheroids embedded in a collagen I matrix, and treated under flow of culture media. Flow cytometry and live-cell confocal imaging were used to measure the interactions and uptake of untargeted liposomes and immunoliposomes in this panel of cell lines. The immunoliposomes retained specific functionality regardless of protein corona formation in high serum environments. As such, spheroids expressing high levels of PD-L1 preferentially internalized immunoliposomes in a 3D environment with extracellular matrix present, while low PD-L1-expressing cell lines showed no preference for either formulation. Importantly, treatments performed in monolayer cultures (on plastic) showed no differences between immuno- and untargeted liposome uptake, including the way in which the endocytosed liposomes are trafficked subcellularly. This study demonstrates the importance of both active and passive accumulation strategies to achieve nanoparticle targeting. Immunoliposomes remain a promising platform for the development of targeted nanotherapies against cervical cancers. However, initial functional tests did not translate directly to biological performance and this should be kept in mind for future formulations. Furthermore, the in vitro model developed appeared useful for visualizing liposome uptake in a 3D, live tissue environment and represents a cost-effective and reproducible model for future studies.
Insights
Anti-PD-L1 immunoliposomes show targeted uptake in 3D cervical cancer models, highlighting the need for advanced in vitro systems for nanotherapy development. This approach may lead to less radical treatments for cervical cancer.
Area of Science:
- Oncology
- Nanotechnology
- Biomedical Engineering
Background:
- Pembrolizumab approval for cervical cancer spurs interest in immunotherapies.
- Targeted nanotherapies offer potential for less radical interventions.
Purpose of the Study:
- To evaluate anti-PD-L1 immunoliposomes in a 3D cervical cancer-on-a-chip model.
- To assess nanoparticle targeting strategies in a relevant in vitro environment.
Main Methods:
- Synthesized anti-PD-L1 immunoliposomes using atezolizumab fragments.
- Utilized 3D spheroids in collagen I matrix under flow conditions.
- Employed flow cytometry and confocal imaging to analyze liposome-cell interactions.
Main Results:
- Immunoliposomes demonstrated specific uptake in high PD-L1 expressing cervical cancer spheroids.
- Targeting was observed in 3D models but not in traditional 2D monolayer cultures.
- Protein corona did not impede immunoliposome functionality in high serum.
Conclusions:
- 3D in vitro models are crucial for evaluating nanoparticle behavior in complex environments.
- Immunoliposomes show promise for targeted cervical cancer nanotherapy.
- Further optimization is needed as in vitro functional tests may not fully predict biological performance.
