Immunotherapy This image depicts cell‐mimicking artificial antigen‐presenting cells (aAPCs, pink) and biological T cells (blue). In article 2203163 by Anshu Agrawal, Abraham P. Lee, and co‐workers, aAPCs are produced using a microfluidic device, which enables facile and stable double emulsion droplet generation. By recapitulating the properties of a cell, namely, size, fluidity, and surface proteins, aAPCs are able to engage with T cells, forming immune synapses. Multiple ligands on aAPCs can engage with the receptors on T cells due to the high surface fluidity of the lipid bilayer. The size of the aAPC (≈20 μm diameter) also contributes to an adequate force that is essential for T cell activation. Experimental results suggest that T cells can tightly bind with the aAPCs and maximize their contact area. After interacting with aAPCs, T cells are activated and subsequently proliferate in large numbers. The background shows a wide spectrum of aAPCs, T cells, and most importantly, aAPC‐T cell pairs joint by immune synapses, as is observed in this research.

In this study, efficient T cell activation is demonstrated using cell‐sized artificial antigen‐presenting cells (aAPCs) with protein‐conjugated bilayer lipid membranes that mimic biological cell membranes. The highly uniform aAPCs are generated by a facile method based on standard droplet microfluidic devices. These aAPCs are able to activate the T cells in peripheral blood mononuclear cells, showing a 28‐fold increase in interferon gamma (IFNγ) secretion, a 233‐fold increase in antigen‐specific CD8 T cells expansion, and a 16‐fold increase of CD4 T cell expansion. The aAPCs do not require repetitive boosting or additional stimulants and can function at a relatively low aAPC‐to‐T cell ratio (1:17). The research presents strong evidence that the surface fluidity and size of the aAPCs are critical to the effective formation of immune synapses essential for T cell activation. The findings demonstrate that the microfluidic‐generated aAPCs can be instrumental in investigating the physiological conditions and mechanisms for T cell activation. Finally, this method demonstrates the feasibility of customizable aAPCs for a cost‐effective off‐the‐shelf approach to immunotherapy.

In this study, efficient T cell activation is demonstrated using cell-sized artificial antigen-presenting cells (aAPCs) with protein-conjugated bilayer lipid membranes that mimic biological cell membranes. The highly uniform aAPCs are generated by a facile method based on standard droplet microfluidic devices. These aAPCs are able to activate the T cells in peripheral blood mononuclear cells (PBMCs), showing a 28-fold increase in IFNg secretion, a 233-fold increase in antigen-specific CD8 T cells expansion, and a 16-fold increase of CD4 T cell expansion. The aAPCs do not require repetitive boosting or additional stimulants and can function at a relatively low aAPC-to-T cell ratio (1-to-17). The research presents strong evidence that the surface fluidity and size of the aAPCs are critical to the effective formation of immune synapses essential for T cell activation. The findings demonstrate that the microfluidic-generated aAPCs can be instrumental in investigating the physiological conditions and mechanisms for T cell activation. Finally, this method demonstrates the feasibility of customizable aAPCs for a cost-effective off-the-shelf approach to immunotherapy.

Phospholipid-stabilized microbubbles are utilized as contrast agents in medical ultrasound imaging, and researchers are currently investigating their potential as theranostic agents. Due to the inadequate water solubility and poor stability of numerous new therapeutics, the development of stable microbubbles with the capacity to encapsulate hydrophobic therapeutics is necessary. Herein, we proposed a flow-focusing microfluidic device to generate highly monodispersed, phospholipid-stabilized dual-layer microbubbles for theranostic applications. The stability and microstructural evolution of these microbubbles were investigated by microscopy and machine-learning-assisted segmentation techniques at different phospholipid and gold nanoparticle concentrations. The double-emulsion microbubbles, formed with the combination of phospholipids and gold nanoparticles, developed a protective gold nanoparticle shell that not only acted as a steric barrier against gas diffusion and microbubble coalescence but also alleviated the progressive dewetting instability and the subsequent cascade of coalescence events.