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T-cell therapies are rapidly emerging for treatment of cancer and other diseases but are limited by inefficient non-viral delivery methods. Acoustofluidic devices are in development to enhance non-viral delivery to cells. The effect of acoustofluidic parameters, such as channel geometry, on molecular loading in human T cells was assessed using 3D-printed acoustofluidic devices. Devices with rectilinear channels (1- and 2-mm diameters) were compared directly with concentric spiral channel geometries. Intracellular delivery of a fluorescent dye (calcein, 100 lg/ml) was evaluated in Jurkat T cells using flow cytometry after ultrasound treatment with cationic microbubbles (2.5% v/v). B-mode ultrasound pulses (2.5 MHz, 3.8 MPa output pressure) were generated by a P4-1 transducer on a Verasonics Vantage ultrasound system. Cell viability was assessed using propidum iodine staining (10 lg/ml). Intracellular molecular delivery was significantly enhanced with acoustofluidic treatment in each channel geometry, but treatment with the 1-mm concentric spiral geometry further enhanced delivery after acoustofluidic treatment compared to both 1- and 2-mm rectilinear channels (ANOVA p < 0.001, n ¼ 6/group). These results indicate that 3Dprinted acoustofluidic devices enhance molecular delivery to T cells, and channel geometry modulates intracellular loading efficiency. This approach may offer advantages to improve manufacturing of T cell therapies. 

Proteinaceous liquid-liquid phase separation (LLPS) occurs when a polypeptide coalesces into a dense phase to form a liquid droplet (i.e., condensate) in aqueous solution. In vivo, functional protein-based condensates are often referred to as membraneless organelles (MLOs), which have roles in cellular processes ranging from stress responses to regulation of gene expression. Late embryogenesis abundant (LEA) proteins containing seed maturation protein domains (SMP; PF04927) have been linked to storage tolerance of orthodox seeds. The mechanism by which anhydrobiotic longevity is improved is unknown. Interestingly, the brine shrimpArtemia franciscanais the only animal known to express such a protein (AfrLEA6) in its anhydrobiotic embryos. Ectopic expression ofAfrLEA6 (AWM11684) in insect cells improves their desiccation tolerance and a fraction of the protein is sequestered into MLOs, while aqueousAfrLEA6 raises the viscosity of the cytoplasm. LLPS ofAfrLEA6 is driven by the SMP domain, while the size of formed MLOs is regulated by a domain predicted to engage in protein binding.AfrLEA6 condensates formed in vitro selectively incorporate target proteins based on their surface charge, while cytoplasmic MLOs formed inAfrLEA6-transfected insect cells behave like stress granules. We suggest thatAfrLEA6 promotes desiccation tolerance by engaging in two distinct molecular mechanisms: by raising cytoplasmic viscosity at even modest levels of water loss to promote cell integrity during drying and by forming condensates that may act as protective compartments for desiccation-sensitive proteins. Identifying and understanding the molecular mechanisms that govern anhydrobiosis will lead to significant advancements in preserving biological samples.