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Biology subjects

Wang, K.-C.

Publications and source records attributed to Wang, K.-C..

4 recordsLinked to original sources

Lesion-specific suppression of YAP/TAZ by biomimetic nanodrug ameliorates atherosclerosis development

Atherosclerosis, characterized by the buildup of lipid-rich plaque on the vessel wall, is the primary cause of myocardial infarction and ischemic stroke. Recent studies have demonstrated that dysregulation of yes-associated protein 1 (YAP) and transcriptional coactivator with PDZ-binding domain (TAZ) contributes to plaque development, making YAP/TAZ potential therapeutic targets. However, systemic modulation of YAP/TAZ expression or activities risks serious off-target effects, limiting clinical applicability. To address the challenge, this study develops monocyte membrane-coated nanoparticles (MoNP) as a drug delivery vehicle targeting activated endothelium lining the plaque surface and utilizes MoNP to deliver verteporfin (VP), a potent YAP/TAZ inhibitor, for lesion-specific treatment of atherosclerosis. The results reveal that MoNP significantly enhance payload delivery to inflamed endothelial cells (EC) while avoiding phagocytic cells, and preferentially accumulate in atherosclerotic regions. MoNP-mediated delivery of VP substantially reduces YAP/TAZ expression, suppressing inflammatory gene expression and macrophage infiltration in cultured EC and mouse arteries exposed to atherogenic stimuli. Importantly, this lesion-targeted VP nanodrug effectively decreases plaque development in mice without causing noticeable histopathological changes in major organs. Collectively, these findings demonstrate a plaque-targeted and pathway-specific biomimetic nanodrug, potentially leading to safer and more effective treatments for atherosclerosis.

bioengineering↗

A versatile method to archive and delipidate brain tissues for ensuing multiplexed immunolabeling and organ-level imaging

Tissue clearing and labeling techniques have revolutionized brain-wide imaging and analysis, yet their application to clinical formalin-fixed paraffin-embedded (FFPE) blocks remains challenging. We introduce HIF-Clear, a novel method for efficiently clearing and labeling centimeter-thick FFPE specimens using elevated temperature and concentrated detergents. HIF-Clear with multi-round immunolabeling reveals neuron circuitry regulating multiple neurotransmitter systems in a whole FFPE mouse brain, and is able to be used as the evaluation of disease treatment efficiency. HIF-Clear also supports expansion microscopy and can be performed on a non-sectioned 15-year-old FFPE specimen, as well as a 3-month formalin-fixed mouse brain. Thus, HIF-Clear represents a feasible approach for researching archived FFPE specimens for future neuroscientific and 3D neuropathological analyses.

bioengineering↗

An M protein coiled coil unfurls and exposes its hydrophobic core to capture LL-37

Surface-associated, coiled-coil M proteins of Streptococcus pyogenes (Strep A) disable human immunity through interaction with select proteins. However, coiled coils lack features typical of protein-protein interaction sites, and it is therefore challenging to understand how M proteins achieve specific binding, for example, with the human antimicrobial peptide LL-37, leading to its neutralization. The crystal structure of a complex of LL-37 with M87 protein, an antigenic M protein variant from a strain that is an emerging threat, revealed a novel interaction mode. The M87 coiled coil unfurled and asymmetrically exposed its hydrophobic core to capture LL-37. A single LL-37 molecule bound M87 in the crystal, but in solution recruited additional LL-37 molecules, consistent with a protein trap neutralization mechanism. The interaction mode visualized crystallographically was verified to contribute significantly to LL-37 resistance in an M87 Strep A strain, and was identified to be conserved in a number of other M protein types that are prevalent in human populations. Our results provide specific detail for therapeutic inhibition of LL-37 neutralization by M proteins.

microbiology↗

Design of M protein immunogens to elicit broadly reactive antibodies against Streptococcus pyogenes

Coiled coil-forming M proteins of the widespread and potentially deadly bacterial pathogen Streptococcus pyogenes (Strep A) are immunodominant targets of opsonizing antibodies. However, antigenic sequence variability into >220 M types, as defined by the M protein hypervariable region (HVR), has been considered to limit its utility as a vaccine immunogen due to type-specificity in the antibody response. Surprisingly, a multi-HVR immunogen in clinical vaccine trials elicited M type cross-reactivity. The basis for this cross-reactivity is unknown but may be due in part to antibody recognition of a three-dimensional (3D) pattern conserved in many M protein HVRs that confers binding to human C4b-binding protein (C4BP). To test this hypothesis, we asked whether a single M protein immunogen carrying the 3D pattern would elicit cross-reactivity against other M types carrying the 3D pattern. We found that a 34-amino acid sequence of M2 protein bearing the 3D pattern retained full C4BP-binding capacity when fused to a coiled coil-stabilizing sequence from GCN4. This immunogen, called M2G, elicited cross-reactive antibodies against a number of M types that carry the 3D pattern but not against those that lack the 3D pattern. The M2G antiserum recognized M proteins as displayed natively on the Strep A surface, and promoted the opsonophagocytic killing of Strep A strains expressing these M proteins. As C4BP-binding is a conserved virulence trait of Strep A, targeting the 3D pattern may prove advantageous in vaccine design.

immunology↗