Biology subjects

Wang, S.-T.

Publications and source records attributed to Wang, S.-T..

8 recordsLinked to original sources

bioRxiv2025

Multimodal profiling of proinflammatory protease activity identifies caspase-1 as a target for lung cancer interception

The systemic inhibition of IL-1b, a key mediator of pulmonary inflammation, has been shown to reduce the incidence of lung cancer in patients in years following treatment, but knowledge gaps surrounding its activation and role in the tumor microenvironment are hindering approaches for cancer interception. We developed a suite of activity-based technologies to probe inflammation in early lung cancer and identified a translational target candidate. We designed probes sensitive to various IL-1b-activating proteases and applied them to a murine model of inflammatory lung cancer, Kras/Trp53-mutant with SIINFEKL expression (KPS). Our nanosensors revealed reduced cleavage of a caspase-1 reporter in the lungs of KPS mice treated with IL-1b antibody, as well as elevated caspase-1 expression and activity in naive tumor tissue sections, highlighting the importance of caspase-1 processing of IL-1b during cancer development. We conducted a pre-clinical trial of a novel combination intervention by administering both IL-1b blockade and caspase-1 inhibition shortly after tumor induction. Following treatment, we observed significant reduction in lung cancer formation, including complete ablation of tumor incidence in nearly 20% of KPS mice. Our approach to understand the interplay of protease activity and cytokine activation supports development of new strategies to mitigate inflammation and intercept lung cancer progression.

bioengineering↗

bioRxiv2024

Engineering Multiplexed Synthetic Breath Biomarkers as Diagnostic Probes

Breath biopsy is emerging as a rapid and non-invasive diagnostic tool that links exhaled chemical signatures with specific medical conditions. Despite its potential, clinical translation remains limited by the challenge of reliably detecting endogenous, disease-specific biomarkers in breath. Synthetic biomarkers represent an emerging paradigm for precision diagnostics such that they amplify activity-based biochemical signals associated with disease fingerprints. However, their adaptation to breath biopsy has been constrained by the limited availability of orthogonal volatile reporters that are detectable in exhaled breath. Here, we engineer multiplexed breath biomarkers that couple aberrant protease activities to exogenous volatile reporters. We designed novel intramolecular reactions that leverage protease-mediated aminolysis, enabling the sensing of a broad spectrum of proteases, and that each release a unique reporter in breath. This approach was validated in a mouse model of influenza to establish baseline sensitivity and specificity in a controlled inflammatory setting and subsequently applied to diagnose lung cancer using an autochthonous Alk-mutant model. We show that combining multiplexed reporter signals with machine learning algorithms enables tumor progression tracking, treatment response monitoring, and detection of relapse after 30 minutes. Our multiplexed breath biopsy platform highlights a promising avenue for rapid, point-of-care diagnostics across diverse disease states.

bioengineering↗

bioRxiv2023

An intravenous DNA-binding priming agent protects cell-free DNA and improves the sensitivity of liquid biopsies

Blood-based, or "liquid," biopsies enable minimally invasive diagnostics but have limits on sensitivity due to scarce cell-free DNA (cfDNA). Improvements to sensitivity have primarily relied on enhancing sequencing technology ex vivo. Here, we sought to augment the level of circulating tumor DNA (ctDNA) detected in a blood draw by attenuating the clearance of cfDNA in vivo. We report a first-in-class intravenous DNA-binding priming agent given 2 hours prior to a blood draw to recover more cfDNA. The DNA-binding antibody minimizes nuclease digestion and organ uptake of cfDNA, decreasing its clearance at 1 hour by over 150-fold. To improve plasma persistence and limit potential immune interactions, we abrogated its Fc-effector function. We found that it protects GC-rich sequences and DNase-hypersensitive sites, which are ordinarily underrepresented in cfDNA. In tumor-bearing mice, priming improved tumor DNA recovery by 19-fold and sensitivity for detecting cancer from 6% to 84%. These results suggest a novel method to enhance the sensitivity of existing DNA-based cancer testing using blood biopsies.

genomics↗

bioRxiv2023

A nanoparticle priming agent reduces cellular uptake of cell-free DNA and enhances the sensitivity of liquid biopsies

Liquid biopsies are enabling minimally invasive monitoring and molecular profiling of diseases across medicine, but their sensitivity remains limited by the scarcity of cell-free DNA (cfDNA) in blood. Here, we report an intravenous priming agent that is given prior to a blood draw to increase the abundance of cfDNA in circulation. Our priming agent consists of nanoparticles that act on the cells responsible for cfDNA clearance to slow down cfDNA uptake. In tumor-bearing mice, this agent increases the recovery of circulating tumor DNA (ctDNA) by up to 60-fold and improves the sensitivity of a ctDNA diagnostic assay from 0% to 75% at low tumor burden. We envision that this priming approach will significantly improve the performance of liquid biopsies across a wide range of clinical applications in oncology and beyond.

genomics↗

bioRxiv2020

Artificial Antigen Presenting Cells for Detection and Desensitisation of Auto-reactive T cells Associated with Type 1 Diabetes

Autoimmune diseases and in particular type 1 diabetes rely heavily on treatments that target the symptoms rather than prevent the underlying disease. One of the barriers to better therapeutic strategies is the inability to detect and efficiently target rare autoreactive T-cell populations that are major drivers of these conditions. Here, we develop a unique artificial antigen presenting cell (aAPC) system from biocompatible polymer particles that allows specific encapsulation of bioactive ingredients. Using our aAPC we demonstrate that we are able to detect rare autoreactive CD4 populations in human patients and using mouse models we demonstrate that our particles are able to induce desensitization in the autoreactive population. This system provides a promising tool that can be used in the prevention of autoimmunity before disease onset.

bioengineering↗

bioRxiv2020

Bent DNA bows as amplifiers and biosensors for detecting DNA-interacting salts and molecules

Due to the central role of DNA, its interactions with inorganic salts and small organic molecules are important for understanding various fundamental cellular processes in living systems, deciphering the mechanism of many diseases related to DNA damages, and discovering or designing inhibitors and drugs targeting DNA. However, there is still a need for improved sensitivity to detect these interactions, especially in situations where expensive sophisticated equipment is not available. Here we report our development and demonstration of bent DNA bows for amplifying, sensing, and detecting the interactions of 14 inorganic salts and small organic molecules with DNA. With the bent DNA bows, these interactions were easily visualized and quantified in gel electrophoresis, which were difficult to measure without bending. In addition, the strength of the interactions of DNA with the various salts/molecules were quantified using the modified Hill equation. This work highlights the amplification effects of the bending elastic energy stored in the DNA bows and the potential use of the DNA bows for quantitatively measuring DNA interactions with small molecules as simple economic methods; it may also pave the way for exploiting the bent DNA bows for other applications such as monitoring water quality and screening DNA-targeting molecules and drugs.

biophysics↗

bioRxiv2019

Pathogenicity of urinary tract infection Escherichia coli in Caenorhabditis elegans

Uropathogenic Escherichia coli (UPEC) is a major bacterial pathogen that causes urinary tract infections (UTIs). Several virulence factors (VFs) in the bacteria have been associated with the pathogenicity. The mouse is an available UTI model for studying the pathogenicity; however, Caenorhabditis elegans represents as an alternative surrogate host for studying UPEC with the capacity for high-throughput analysis. Therefore, we established a simple assay for a UPEC infection model with C. elegans for large-scale screening. An E. coli culture to be tested and synchronized C. elegans were mixed in 96-well plates, and the pathogenicity was determined by comparison of the turbidity before and after incubation. A total of 133 clinically isolated E. coli strains, which included UTI-associated and fecal isolates, were applied to demonstrate the liquid pathogenicity assay. The E. coli isolates associated with UTIs showed higher pathogenicity in C. elegans than the fecal isolates, suggesting that the simple assay with C. elegans is useful as a UPEC infectious model. From the screening, VFs involved with iron acquisition (chuA, fyuA, and irp2) were significantly associated with high pathogenicity. C. elegans is a heme auxotroph, and iron homeostasis also serves innate immunity in C. elegans. We then evaluated whether the VFs in UPEC were involved in the pathogenicity. Mutants of E. coli UTI89 with defective iron acquisition systems were applied to a solid killing assay with C. elegans. As a result, the survival rate of C. elegans fed with the mutants significantly increased compared to when fed with the parent strain. To our knowledge, this is the first report of the involvement of iron acquisition in the pathogenicity of UPEC in a C. elegans model.

microbiology↗

bioRxiv2019

Retinoic acid promotes in vitro development of haploid germ cells from pre-pubertal porcine spermatogenic cells

Spermatogonial stem cells (SSCs) self-renew and contribute genetic information to the next generation. Inducing directional differentiation of porcine SSCs may be an important strategy in exploring the mechanisms of spermatogenesis and developing better treatment methods for male sterility. Here, we established an in vitro culture model for porcine small seminiferous tubule segments, to induce SSCs to differentiate into single-tail haploid spermatozoa. The culture model subsequently enabled spermatozoa to express the sperm-specific protein acrosin, and oocytes to develop to blastocyst stage after round spermatid injection. The addition of retinoic acid (RA) to the differentiation media promoted the efficiency of haploid differentiation. RT-PCR analysis indicated that RA stimulated the expression of Stra8 but reduced the expression of NANOS2 in spermatogonia. Genes involved in post-meiotic development, Prm1 and Tnp1, were up-regulated in the presence of RA. The addition of RAR inhibitor, BMS439, showed that RA enhanced the expression of cAMP responsive-element binding protein through RAR, and promoted the formation of round spermatids.

developmental biology↗