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Perriman, A. W.

Publications and source records attributed to Perriman, A. W..

5 recordsLinked to original sources

Extrahepatic, cell-specific delivery of LNPs through competitive inhibition of ApoE-mediated uptake

Targeted lipid nanoparticles (LNPs) for extrahepatic drug delivery are limited by apolipoprotein E (ApoE)-mediated hepatic accumulation. We developed NanoPilot, a modular fusion protein platform comprising antibodies and anchors blocking the low density lipoprotein receptor (LDLR) ApoE binding site, to block LNP liver uptake and redirect to target cells. NanoPilot can be applied to preformulated LNPs in 10 minutes with two pipetting steps. In vitro, an anti-CD3{varepsilon} NanoPilot increased T-cell transfection 40-fold and reduced monocyte transfection 10-fold in human peripheral blood mononucleocytes. In immunocompetent mouse models, NanoPilot-coated LNPs achieved 30-40% splenic and hepatic T-cell transfection whilst bulk liver accumulation was reduced 3-fold. An anti-c-Kit NanoPilot was further shown to enhance delivery to a haematopoietic stem cell-like cell line in an in-vitro co-culture assay. NanoPilot establishes a versatile framework for the systemic delivery of genetic therapies through concomitant cell-specific targeting and off-target blocking. Further research will assess potential clinical applications.

biochemistry↗

Damping nonlinearity in agarose hydrogels under relative humidity: balancing network stiffness and energy dissipation

Sustainable, biodegradable elastomers are needed to replace fossil-based alternatives and reduce the environmental impact of traditional vibration damping materials. We investigate agarose-based hydrogels as eco-friendly vibration absorbers, examining the combined effects of polymer concentration (1-7 wt%), relative humidity (55-98%), and mechanical pre-stress on their dynamic mechanical properties. Frequency-dependent viscoelastic and vibration transmissibility tests, supported by Gaussian Process Regression (GPR), reveal that increasing agarose concentration enhances the storage modulus (E') by over an order of magnitude, reaching[~] 5 MPa depending on humidity and applied prestress. Remarkably, the damping efficiency--characterised by the loss factor (tan(d))--exhibits a highly non-monotonic trend. Maximum energy dissipation is observed at intermediate network densities, with tan(d) up to 0.21 and a loss modulus of[~] 515 kPa at 5 w% and 75% relative humidity, comparable to synthetic elastomers. GPR analysis shows that prestress controls nonlinear stiffening and transmissibility resonance behavior, while shifting peak damping from 5 wt% to 1 wt% agarose as prestress increases. These findings underscore the mechanical tunability and sustainability of agarose hydrogels, providing potential design guidance for biodegradable vibration mitigation materials.

bioengineering↗

Tunable porosity in a hydrogel with extreme vibration damping properties

We have developed hydrogel systems with tunable porosity through dialysis casting by varying alginate and poloxamer compositions from 0% to 10%. These gels feature diverse porosity topologies, yielding loss factors between 16% and 29% in the 50 Hz to 300 Hz frequency range. The dynamic modulus shows a remarkable increase of over an order of magnitude, reaching approximately 3 MPa compared to the static modulus. Vibration transmissibility tests and dynamic mechanical analysis reveal that the poroelastic and pneumatic-like effects from the tunable porous structures contribute significantly to this damping effect. Furthermore, these hydrogels are biosourced and biodegradable, providing a sustainable alternative to conventional fossil-based damping materials.

bioengineering↗

The Immobilization of Hyaluronic Acid in 3D Hydrogel Scaffolds Modulates Macrophage Polarization

Macrophages are key modulators of immunity, tissue homeostasis and disease development. As our understanding of macrophage biology and their tissue specific behaviors grow the necessity to model macrophages within a 3D biomimetic environment becomes increasingly apparent. Numerous hydrogels have been developed and explored for this purpose, extracellular matrix (ECM) mimicking hydrogels gaining a special interest. In this study, we present the use of such a hydrogel composed of collagen and hyaluronic acid (HA), two of the major ECM components, for the 3D culture of macrophages to model their role in different tissues and diseases. We demonstrate the ability to tailor the mechanical properties of the hydrogel through formulation modulation. Human macrophages retain morphology, viability, and expression of key cell surface markers when 3D cultured within the hydrogel. Interestingly, we demonstrate in this work, that independent of mechanical properties, by adjusting the composition of the hydrogel, specifically HA molecular weight, we can steer macrophage polarization towards either a pro-inflammatory or anti-inflammatory phenotype. This HA-dependent modulation of macrophage behavior is nullified if the HA is chemically crosslinked, shedding light on the impact of one of the most commonly used preparation methods for collagen-HA hydrogels on macrophage behavior. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=84 SRC="FIGDIR/small/588451v1_ufig1.gif" ALT="Figure 1"> View larger version (20K): org.highwire.dtl.DTLVardef@1cbe667org.highwire.dtl.DTLVardef@1837e58org.highwire.dtl.DTLVardef@1dbdbc6org.highwire.dtl.DTLVardef@139d65b_HPS_FORMAT_FIGEXP M_FIG C_FIG Hyaluronic acid (HA) is an extracellular matrix component, which can modulate the polarization of macrophages. The chemical crosslinking of HA to hydrogel scaffolds counteracts the cell signaling role of this molecule, preventing HA from modulating the immune polarization of macrophages within the model. Key pointsO_LICollagen-HA hydrogels form suitable biomimetic niches for the 3D culture of human macrophages in which hydrogel composition modulates macrophage phenotype, specifically the presence and molecular weight of HA. C_LIO_LIPolarization of macrophage phenotype by HA is nullified if HA is chemically cross-linked within the hydrogel. C_LI

bioengineering↗

Controlling protein nanocage assembly with hydrostatic pressure

Controlling the assembly and disassembly of nanoscale protein cages for the capture and internalisation of protein or non-proteinaceous components is fundamentally important to a diverse range of bionanotechnological applications. Here, we study the reversible, pressure-induced dissociation of a natural protein nanocage, E. coli bacterioferritin (Bfr), using synchrotron radiation small angle X-ray scattering (SAXS) and circular dichroism (CD). We demonstrate that hydrostatic pressures of 450 MPa are sufficient to completely dissociate the Bfr icositetramer into protein dimers, and the reversibility and kinetics of the reassembly process can be controlled by selecting appropriate buffer conditions. We also demonstrate that the heme B prosthetic group present at the subunit dimer interface influences the stability and pressure lability of the cage, despite its location being discrete from the inter-dimer interface that is key to cage assembly. This indicates a major cage-stabilising role for heme within this family of ferritins.

biophysics↗