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Biology subjects

Speed, S.

Publications and source records attributed to Speed, S..

4 recordsLinked to original sources

Optimizing an avian influenza vaccine using a novel Bacterial Enzymatic Combinatorial Chemistry (BECC) TLR4 adjuvant

The development of broadly protective and dose-sparing influenza vaccines remains a critical challenge, particularly for zoonotic H5N1 strains with pandemic potential. This study evaluates BECC470s, a synthetic TLR4 adjuvant, for its ability to enhance the immunogenicity and protective efficacy of recombinant H5 hemagglutinin (rHA) vaccination in murine models. BECC470s-adjuvanted rHA elicited robust IgG1/IgG2a antibody responses and complete survival following homologous 2004 H5N1 challenge in a prime-boost model. Although BECC470s broadened antibody binding to both variable HA head and conserved stalk domains by ELISA, functional neutralizing antibody responses were restricted to the matched 2004 H5N1 isolate, with no detectable neutralization of H5N1 viruses isolated in 2022 or 2024. These data indicate that BECC470s enhances the magnitude and apparent breadth of binding antibody responses while maintaining strain-specific neutralizing activity, supporting its potential as an adjuvant for next-generation influenza vaccines while underscoring the need for further optimization to achieve true cross-neutralizing protection.

immunology↗

LASSO: versatile and selective biomolecule pulldown with combinatorial DNA-crosslinked polymers

Current methods for sequence-selective biomolecule isolation suffer from high cost, off-target effects, and limited flexibility. Here, we introduce LASSO (crossLink-Assisted Sequence-Selective isOlation), a versatile platform using programmable polymer phase separation to capture biomolecules under native conditions. LASSO relies on combinatorial crosslinker libraries--diverse mixtures of DNA strands that collectively trigger the formation of highly swollen polymer agglomerates with near-zero background binding. We demonstrate >80% pulldown efficiency for diverse targets, including DNA, SARS-CoV-2 RNA, and human thrombin. LASSO provides 8-20x higher binding capacity (4 nmol/mg polymer) than commercial microbeads. In RNA-seq workflows, LASSO depleted ribosomal RNA with 86% efficiency while yielding up to 7x fewer off-target outliers (p<0.001) versus state-of-the-art magnetic beads (riboPOOLs) and RNase H (NEBNext) kits. Thrombin was captured via switchable aptamers with 92% efficiency, and a gentle release mechanism allowed the subsequent isolation of 72% enzymatically active proteins from the polymer. LASSOs cost-effectiveness ($0.96/sample vs. $46-$51 for commercial kits), long-term stability (7+ years), simple usage, and modularity position it to transform diagnostics, transcriptomics, and bionanotechnology workflows.

bioengineering↗

Enhancing protective efficacy and immunogenicity of hemagglutinin-based influenza vaccine utilizing adjuvants developed by BECC

Seasonal influenza viruses continue to pose a significant threat, causing substantial morbidity and mortality in the US and worldwide despite the availability of vaccines and antivirals. These challenges may be addressed by improving vaccine immunogenicity through the inclusion of adjuvants that enhance immune responses against key antigens including influenza hemagglutinin (HA). BECC (Bacterial Enzymatic Combinatorial Chemistry) adjuvants are novel Toll-like Receptor 4 (TLR4) ligands created by modifying enzymes from lipid A synthesis pathways in Gram-negative bacteria. This study compares the ability of the biological and synthetic versions of these adjuvants to enhance the efficacy of recombinant HA (rHA) antigens in mouse influenza virus challenge. Mice immunized with rHA adjuvanted with BECCs stimulate the humoral and cell-mediated arms of the immune system without exhibiting cytotoxicity/pyrogenicity. A robust HA-specific immunoglobulin subtype, especially IgG2a, response was observed in mice adjuvanted with BECCs as compared to control adjuvants, MPL, and PHAD Further, animals adjuvanted with BECC470 cleared infection seven days post-infection, demonstrating their potential for further translational development. Vaccination adjuvanted with BECCs were also able to increase immune recognition of linear B and T cell epitopes when compared to control adjuvants, as well as induce durable immune response eighteen months post-vaccination. Together, these findings indicate that BECCs may serve as highly effective adjuvants in influenza vaccination. One Sentence Summary: Efficacy of engineered lipid A molecules as adjuvants for HA-based influenza vaccine

immunology↗

Assembling a true "Olympic Gel" from >16,000 combinatorial DNA rings

Olympic gels are an elusive form of soft matter, comprising a three-dimensional network of mechanically interlocked cyclic molecules. In the absence of defined network junctions, the high conformational freedom of the molecules was previously theorized to confer unique mechanical properties to Olympic gels, such as non-linear elasticity and unconventional swelling characteristics. However, the synthesis of an Olympic gel exhibiting these intriguing features is challenging, since unintended crosslinking and polymerization processes are often favored over cyclization. Here, we report the successful assembly of a true Olympic gel from a library of DNA rings comprising more than 16,000 distinct molecules. Each of these rings contains a unique sequence domain that can be enzymatically activated to produce reactive termini that favor intramolecular cyclization. We characterized the genetic, mechanical, and structural characteristics of the material by next-generation sequencing, oscillatory rheology, large-scale computational simulations, atomic force microscopy, and cryogenic electron microscopy. Our results confirm the formation of a stable Olympic gel, which exhibits unique swelling behavior and an elastic response that is exclusively determined by entanglements, yet persists on long time scales. By combining concepts from polymer physics, synthetic biology, and DNA nanotechnology, this new material class provides a flexible experimental platform for future studies into the effects of network topology on macroscopic material properties and its function as a carrier of genetic information in biological and biomimetic systems. This work moreover demonstrates that exotic material properties can emerge in systems with a high compositional complexity that is more reminiscent of biological than synthetic matter.

bioengineering↗