611 Exploiting T cells as vehicles of liposomal SHP2i to enhance adoptive cell therapy

BackgroundAdoptive T cell therapy (ACT) is often accompanied by supporting immunomodulatory drugs to protect T cells from the suppressive tumor microenvironment (TME) [1]. However, systemic administration of these immunomodulators can cause serious side effects and fail to distribute optimally to exert sufficient lymphocyte stimulation within the tumor and lymphoid compartments. Loading T cells with adjuvant drugs or cytokines prior to cell transfer provides a solution to this issue, showing the potential to use T cells as vehicles to carry immunomodulatory molecules to target sites [2]. SHP2 is an important hub connecting several intracellular oncogenic signaling pathways including PD-1/PD-L1, representing a notable target for cancer immunotherapy. SHP2 inhibition has been shown to elicited tumor regression by improving CD8+ T cells activity [3]. Herein we present a lipid nanoparticle system encapsulating an SHP2 inhibitor (SHP2i) that allows high T cell loading capacity and enhances their therapeutic activity.MethodsRemote-loading gradients were used to achieve high encapsulation efficiency of SHP2i into the lipid nanoparticle platform. Mouse cytotoxic T cells were loaded with SHP2i, and loading efficiency and release rates from the T cells were evaluated in vitro. Flow cytometry was used to assess T cell viability, proliferation, and phenotype. In vivo biodistribution of loaded T cells was evaluated by labeling lipid nanoparticles with gadolinium and T cells with Cell-trace-marker, which were measured with ICP-MS and Flow respectively. The therapeutic anti-tumor efficacy of the loaded T cells was demonstrated on EG.7-OVA tumor-bearing mice.ResultsThe developed formulation allowed high T cell loading efficiency of SHPi and extended-release over 5 days. Loading T cells with lipid formulated SHP2i did not compromise cell viability and proliferation and resulted in T cells retaining a central memory phenotype than unloaded counterparts. Adoptively transferred T cells loaded with lipid nanoparticles showed the same distribution and proliferation behavior as the unloaded T cells in vivo, accumulating into tumor tissue three days post cell infusion. Loaded OT.I T cells significantly improved tumor growth inhibition and overall survival than OT.I T cells alone, with 5 out of 6 mice completely tumor-free, resulting in durable long-term responders.ConclusionsLoading T cells with liposomal SHP2i before ACT allowed specific and controlled delivery of immunomodulatory drugs by T cells. The loaded T cells showed improved anti-tumor efficacy. The developed lipid formulation allows the loading of a variety of immunomodulatory drugs to T cells, which serve both as a drug delivery vehicle and enhance the tumor efficacy of the transferred cells.ReferencesWaldman AD, Fritz JM, Lenardo MJ. A guide to cancer immunotherapy: from T cell basic science to clinical practice. Nat. Rev. Immunol. 2020. p. 651–68.Combes F, Meyer E, Sanders NN. Immune cells as tumor drug delivery vehicles. J Control Release. Elsevier; 2020;327:70–87.Yuan X, Bu H, Zhou J, Yang CY, Zhang H. Recent Advances of SHP2 Inhibitors in Cancer Therapy: Current Development and Clinical Application. J Med Chem. 2020;63:11368–96.Ethics ApprovalThe study has been approved by the Danish Animal Experiments Inspectorate with the permit number 2020-15-0201-00482. The participants gave informed consent before taking part.

Textile-based cyanobacteria biocomposites for potential environmental remediation applications

Microalgae and cyanobacteria are effective platforms for environmental remediation (phycoremediation), particularly of air and water. There is limited scope to deploy suspension cultures due to space, cost and maintenance challenges—driving an imperative towards biofilm-based treatment systems; however, these systems are ill-equipped for rapid and mobile deployment. In this study we explored the main technical challenges to developing cheap, accessible and low-maintenance engineered biofilm systems (biocomposites) comprising cyanobacteria (Synechococcus elongatus) immobilised to a range of textiles (n = 4) by natural or synthetic latex binders (n = 16), chitosan or shellac. Biocomposite viability (measured as net CO2 uptake) was assessed over 20 days in semi-batch trials. No maintenance was required during this period as the humidity within the reactor was sufficient to support metabolism. Two commercial natural latex binders (AURO 320 and 321) supported strong growth within the biocomposite, outperforming suspension controls. There was variation in textiles performance, with an 80/20 polyester-cotton blend performing most consistently. Biocomposite formulation was varied in terms of binder solids content and cell loading rate, with 5% solids and 2.5% cell loading the most effective combination. We demonstrate the technical feasibility of fabricating functional textile-based cyanobacteria biocomposites and discuss this within the context of developing decentralised wastewater treatment services.

Heterogeneous toroidal spiral particles for islet encapsulation

Self-assembled toroidal-spiral particles were generated to encapsulate human islets of Langerhans with high cell loading and excellent cell viability.

Double Emulsion Picoreactors for High-Throughput Single-Cell Encapsulation and Phenotyping via FACS

ABSTRACTIn the past five years, droplet microfluidic techniques have unlocked new opportunities for the high-throughput genome-wide analysis of single cells, transforming our understanding of cellular diversity and function. However, the field lacks an accessible method to screen and sort droplets based on cellular phenotype upstream of genetic analysis, particularly for large and complex cells. To meet this need, we developed Dropception, a robust, easy-to-use workflow for precise single-cell encapsulation into picoliter-scale double emulsion droplets compatible with high-throughput phenotyping via fluorescence-activated cell sorting (FACS). We demonstrate the capabilities of this method by encapsulating five standardized mammalian cell lines of varying size and morphology as well as a heterogeneous cell mixture of a whole dissociated flatworm (5 - 25 μm in diameter) within highly monodisperse double emulsions (35 μm in diameter). We optimize for preferential encapsulation of single cells with extremely low multiple-cell loading events (<2% of cell-containing droplets), thereby allowing direct linkage of cellular phenotype to genotype. Across all cell lines, cell loading efficiency approaches the theoretical limit with no observable bias by cell size. FACS measurements reveal the ability to discriminate empty droplets from those containing cells with good agreement to single-cell occupancies quantified via microscopy, establishing robust droplet screening at single-cell resolution. High-throughput FACS phenotyping of cellular picoreactors has the potential to shift the landscape of single-cell droplet microfluidics by expanding the repertoire of current nucleic acid droplet assays to include functional screening.ABSTRACT FIGURE