Cell delivery

Islet transplantation for type 1 diabetes management is hindered by the life-long need for immunosuppressive medications. Here, the authors report an islet encapsulation device with local anti-rejection drug release that achieves long-term diabetes reversal in male rats and reduces drug-related toxicity.

Transplanting encapsulated insulin-producing cells may achieve a functional cure for type 1 diabetes, but efficacy is constrained by mass transfer limits. Here, the authors report a dynamic computational platform to investigate the therapeutic potency of such programmable bioartificial pancreas devices.

Biocontainment is a key to developing safe genetically-engineered microbes (GEMs). Here the authors demonstrate genetically stable CRISPR-based kill switches that control GEMs’ viability in animal hosts, enabling their safe biomedical applications.

Cell encapsulation into biomaterials for transplantation is currently limited by inadequate oxygenation. Here the authors present a biomimetic scaffold featuring internal continuous air channels endowed with 10,000-fold higher O2 diffusivity than hydrogels and demonstrate correction of diabetes in immunocompetent mice using rat islets for over 6 months.

Protein delivery with cell-penetrating peptides suffers from ineffective endosomal escape and low tolerance in serum, thereby limiting treatment success. Here the authors present an intracellular protein delivery system and demonstrate efficient delivery in vitro and therapeutic efficacy in a liver failure model in vivo.

Despite recent progress to advance cardiac cell-based therapy for patients, heart failure mortality rivals most cancers. Here, the authors describe an approach to control and pattern 3 distinct human cardiac cell populations to promote superior repair and regeneration after myocardial infarction.

The type III secretion system (T3SS) of bacteria can be used to inject cargo into eukaryotic cells but its lack of target specificity is a disadvantage. Here the authors place the T3SS under the regulation of light by engineering optogenetic switches into the dynamic cytosolic T3SS component SctQ.

Oral microbiota delivery is an approach to treat and prevent disease but suffers from low retention and bioavailability. Here the authors report on a lipid coating to protect against environmental assault maintaining viability and bioactivity of the bacteria and demonstrate effective application in a colitis model.

Most reagents designed to deliver cargo into cells are cationic and so cannot deliver cationic cargo. Here the authors show that pretreating cells with the anionic polymer poly(propylacrylic acid) facilitates the uptake and endosomal escape of a wide variety of cationic cargo in numerous cell types.

To enter the cells, nanomaterials often need covalent conjugation with cell-penetrating ligands such as TAT. Here, the authors show that simple mixing with TAT-coupled nanoparticles enables the cellular uptake of unfunctionalized nanoparticles, and its activity is stimulated by cysteine in the medium.

The use of engineered bacteria for biomedical applications is limited by side effects such as inflammatory response. Here the authors engineer cell membrane coated bacteria as in vivo tumor imaging agents, and show that these generate a lower inflammatory response and reduced macrophage clearance.

The incorporation of cells into tissue engineering scaffolds can be a major challenge. Here, the authors report on anchoring thrombin to cell membranes for the in situ formation of fibrin scaffolds around the modified cells, demonstrate scaffold formation in vitro and show cell survival in vivo.

Therapeutic peptide nucleic acids can be delivered into cells by conjugation to cell penetrating peptides (CPPs), but efficiency is usually low. Here the authors use synthetic molecular evolution and a luciferase-based library screen to generate new CPPs with improved efficiency and lower toxicity.

Quantum dots (QDs) mimic delivery agents for drugs and analytic compounds, but which route do they take inside cells? Here, the authors developed a technique to follow QDs, and they show that zwitterionic nanoparticle surface coatings make for the best delivery vehicle.

Cell-based hormone replacement therapy (cHRT) may be an alternative therapy to pharmacological (p)HRT. Here, the authors show that implanted 3D bioengineered ovarian constructs of granulosa and theca cells in ovariectomized rats recapitulate native cell interactions and improve efficacy compared to similar doses of pHRT.