Publications by authors named "Weiwei Aileen Li"

Unlabelled: Mechanical properties of the extracellular microenvironment are known to alter cellular behavior, such as spreading, proliferation or differentiation. Previous studies have primarily focused on studying the effect of matrix stiffness on cells using hydrogel substrates that exhibit purely elastic behavior. However, these studies have neglected a key property exhibited by the extracellular matrix (ECM) and various tissues; viscoelasticity and subsequent stress-relaxation.

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DNA nanostructures have evoked great interest as potential therapeutics and diagnostics due to ease and robustness of programming their shapes, site-specific functionalizations and responsive behaviours. However, their utility in biological fluids can be compromised through denaturation induced by physiological salt concentrations and degradation mediated by nucleases. Here we demonstrate that DNA nanostructures coated by oligolysines to 0.

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Therapeutic cancer vaccines aim to induce durable antitumor immunity that is capable of systemic protection against tumor recurrence or metastatic disease. Many approaches to therapeutic cancer vaccines have been explored, with varying levels of success. However, with the exception of Sipuleucel T, an ex vivo dendritic cell vaccine for prostate cancer, no therapeutic cancer vaccine has yet shown clinical efficacy in phase 3 randomized trials.

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Biomaterial scaffold based vaccines show significant potential in generating potent antigen-specific immunity. However, the role of the scaffold surface chemistry in initiating and modulating the immune response is not well understood. In this study, a mesoporous silica micro-rod (MSR) scaffold was modified with PEG, PEG-RGD and PEG-RDG groups.

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Implanting materials in the body to program host immune cells is a promising alternative to transplantation of cells manipulated ex vivo to direct an immune response, but doing so requires a surgical procedure. Here we demonstrate that high-aspect-ratio, mesoporous silica rods (MSRs) injected with a needle spontaneously assemble in vivo to form macroporous structures that provide a 3D cellular microenvironment for host immune cells. In mice, substantial numbers of dendritic cells are recruited to the pores between the scaffold rods.

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Three-dimensional macroporous scaffolds have extensively been studied for cell-based tissue engineering but their use is mostly limited to mechanical support for cell adhesion and growth on the surface of macropores. Here, a templated fabrication method is described to prepare cell-friendly inverse opal-like hydrogels (IOHs) allowing both cell encapsulation within the hydrogel matrix and cell seeding on the surface of macropores. Ionically crosslinked alginate microbeads and photocrosslinkable biocompatible polymers are used as a sacrificial template and as a matrix, respectively.

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The in vivo enrichment of dendritic cells (DCs) in implanted macroporous scaffolds is an emerging strategy to modulate the adaptive immune system. The pore architecture is potentially one of the key factors in controlling enrichment of DCs. However, there have been few studies examining the effects of scaffold pore structure on in vivo DC enrichment.

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Immunotherapy is a promising approach for treating cancer. However, there are limitations inherent to current approaches which may be addressed by integrating them with biomaterial-based strategies. Material platforms have been fabricated to interact with immune cells through spatially controlled and temporally controlled delivery of immune modulators and to promote immune cell crosstalk.

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