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Wang, S. J.

Publications and source records attributed to Wang, S. J..

4 recordsLinked to original sources

A generalizable system for antigenic peptide targeting across HLA-I allotypes

T cell receptors (TCRs) and TCR-mimicking antibodies recognize peptide antigens in the context of specific Human Leucocyte Antigen (HLA-I) allotypes, and the extreme polymorphism of the HLA locus limits the breadth of immunotherapy development. Key barriers include divergent molecular surfaces on HLA proteins and differences in the peptide structure. As a result, existing modalities cannot confer therapeutic coverage across patients of divergent genetic backgrounds. Here, we develop an approach which combines a peptide conformational prediction tool, PepPred, with a cross-HLA binding protein engineering system, TRACeR-I1, to outline a generalized framework for developing binders (xTRACeRs) with compatibility across HLA allotypes while maintaining high levels of specificity towards the peptide antigen. We use our system to develop and validate xTRACeRs against clinically relevant, established peptide antigens presented across common alleles within five HLA-A/B/C supertypes2. Cryo-EM structures of xTRACeR-pHLA complexes for an oncofetal antigen from PRAME and a neuroblastoma-specific peptide from PHOX2B reveal effective mechanisms to navigate polymorphic HLA surface residues, and extensive interactions with the peptide. We implemented these two xTRACeRs as Chimeric Antigen Receptor (CAR) T cells and demonstrated their potent killing efficacy and specificity. Overcoming restriction across HLA supertypes lifts a key barrier in HLA-targeted immunotherapy by expanding patient coverage.

synthetic biology↗

Identification of Small Molecule Dimethyoxyphenyl Piperazine Inhibitors of Alpha-Synuclein Fibril Growth

Identification of Small Molecule Dimethyoxyphenol Piperazine Inhibitors of Alpha-Synuclein Fibril Growth Alpha-synuclein (asyn) fibril accumulation is the defining feature of Parkinson disease and is a target for disease-modifying treatments. One therapeutic strategy to reduce fibril accumulation is inhibition of asyn fibril growth. We developed a sensitive fluorescence-based fibril growth assay to screen for small molecule inhibitors. After validating the inhibition assay using a previously identified inhibitor, epigallocatechin-3-gallate, we identified compound 1 as a lead for inhibition of fibril growth. We analysed structure-activity relationships with analogs of 1 to optimize inhibition potency. Our results identified two dimethoxyphenyl piperazine analogs with more potent inhibition of in-vitro assembled fibrils. These analogs also inhibited the growth of asyn fibrils amplified from Lewy Body Disease brain tissue, further validating the inhibitor screening assay. Molecular docking studies indicate that these compounds can bind to the fibril ends, suggesting a potential capping mechanism through which these compounds inhibit the sequential association of monomeric asyn required for fibril growth.

neuroscience↗

Polyfunctional IL-21+ IFNg+ T follicular helper cells contribute to checkpoint inhibitor diabetes mellitus and can be targeted by JAK inhibitor therapy

Immune checkpoint inhibitors (ICI) have revolutionized cancer therapy, but their use is limited by the development of autoimmunity in healthy tissues as a side effect of treatment. Such immune-related adverse events (IrAE) contribute to hospitalizations, cancer treatment interruption and even premature death. ICI-induced autoimmune diabetes mellitus (ICI-T1DM) is a life-threatening IrAE that presents with rapid pancreatic beta-islet cell destruction leading to hyperglycemia and life-long insulin dependence. While prior reports have focused on CD8+ T cells, the role for CD4+ T cells in ICI-T1DM is less understood. Here, we identify expansion CD4+ T follicular helper (Tfh) cells expressing interleukin 21 (IL-21) and interferon gamma (IFN{gamma}) as a hallmark of ICI-T1DM. Furthermore, we show that both IL-21 and IFN{gamma} are critical cytokines for autoimmune attack in ICI-T1DM. Because IL-21 and IFN{gamma} both signal through JAK-STAT pathways, we reasoned that JAK inhibitors (JAKi) may protect against ICI-T1DM. Indeed, JAKi provide robust in vivo protection against ICI-T1DM in a mouse model that is associated with decreased islet-infiltrating Tfh cells. Moreover, JAKi therapy impaired Tfh cell differentiation in patients with ICI-T1DM. These studies highlight CD4+ Tfh cells as underrecognized but critical mediators of ICI-T1DM that may be targeted with JAKi to prevent this grave IrAE. VISUAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=92 SRC="FIGDIR/small/625710v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@ed4acdorg.highwire.dtl.DTLVardef@c9e062org.highwire.dtl.DTLVardef@1aa81eforg.highwire.dtl.DTLVardef@1388747_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Track-A-Worm 2.0: A Software Suite for Quantifying Properties of C. elegans Locomotion, Bending, Sleep, and Action Potentials

Comparative analyses of locomotor behavior and cellular electrical properties between wild-type and mutant C. elegans are crucial for exploring the gene basis of behaviors and the underlying cellular mechanisms. Although many tools have been developed by research labs and companies, their application is often hindered by implementation difficulties or lack of features specifically suited for C. elegans. Track-A-Worm 2.0 addresses these challenges with three key components: WormTracker, SleepTracker, and Action Potential (AP) Analyzer. WormTracker accurately quantifies a comprehensive set of locomotor and body bending metrics, reliably distinguish between the ventral and dorsal sides, continuously tracks the animal using a motorized stage, and seamlessly integrates external devices, such as a light source for optogenetic stimulation. SleepTracker detects and quantifies sleep-like behavior in freely moving animals. AP Analyzer assesses the resting membrane potential, afterhyperpolarization level, and various AP properties, including threshold, amplitude, mid-peak width, rise and decay times, and maximum and minimum slopes. Importantly, it addresses the challenge of AP threshold quantification posed by the absence of a pre-upstroke inflection point. Track-A-Worm 2.0 is potentially a valuable tool for many C. elegans research labs due to its powerful functionality and ease of implementation.

neuroscience↗