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Biology subjects

Qui, M.

Publications and source records attributed to Qui, M..

5 recordsLinked to original sources

Development of a Time-Resolved Fluorescence Resonance Energy Transfer ultra-high throughput screening assay for targeting SYK and FCER1G interaction

The spleen tyrosine kinase (SYK) and high affinity immunoglobulin epsilon receptor subunit gamma (FCER1G) interaction has a major role in the normal innate and adaptive immune responses, but dysregulation of this interaction is implicated in several human diseases, including autoimmune disorders, hematological malignancies, and Alzheimers Disease. Development of small molecule chemical probes could aid in studying this pathway both in normal and aberrant contexts. Herein, we describe the miniaturization of a time-resolved fluorescence resonance energy transfer (TR-FRET) assay to measure the interaction between SYK and FCER1G in a 1536-well ultrahigh throughput screening (uHTS) format. The assay utilizes the His-SH2 domains of SYK, which are indirectly labeled with anti-His-terbium to serve as TR-FRET donor and a FITC-conjugated phosphorylated ITAM domain peptide of FCER1G to serve as acceptor. We have optimized the assay into 384-well HTS format and further miniaturized the assay into a 1536-well uHTS format. Robust assay performance has been achieved with a Z factor > 0.8 and signal-to-background (S/B) ratio > 15. The utilization of this uHTS TR-FRET assay for compound screening has been validated by a pilot screening of 2,036 FDA-approved and bioactive compounds library. Several primary hits have been identified from the pilot uHTS. One compound, hematoxylin, was confirmed to disrupt the SYK/FECR1G interaction in an orthogonal protein-protein interaction assay. Thus, our optimized and miniaturized uHTS assay could be applied to future scaling up of a screening campaign to identify small molecule inhibitors targeting the SYK and FCER1G interaction.

pharmacology and toxicology↗

A multiplexed time-resolved fluorescence resonance energy transfer ultrahigh-throughput screening assay for targeting SMAD4-SMAD3-DNA complex

The signaling pathway of transforming growth factor-beta (TGF{beta}) plays crucial roles in the establishment of an immunosuppressive tumor microenvironment, making anti-TGF{beta} agents a significant area of interest in cancer immunotherapy. However, the clinical translation of current anti-TGF{beta} agents that target upstream cytokines and receptors remains challenging. Therefore, the development of small molecule inhibitors specifically targeting SMAD4, the downstream master regulator of TGF{beta} pathway, would offer an alternative approach with significant therapeutic potential for anti-TGF-{beta} signaling. In this study, we present the development of a cell lysate-based multiplexed time-resolved fluorescence resonance energy transfer (TR-FRET) assay in an ultrahigh-throughput screening (uHTS) 1536-well plate format. This assay enables simultaneous monitoring of the protein-protein interaction (PPI) between SMAD4 and SMAD3, as well as the protein-DNA interaction (PDI) between SMADs and their consensus DNA binding motif. The multiplexed TR-FRET assay exhibits high sensitivity, allowing the dynamic analysis of the SMAD4-SMAD3-DNA complex at single amino acid resolution. Moreover, the multiplexed uHTS assay demonstrates robustness for screening small molecule inhibitors. Through a pilot screening of an FDA-approved and bioactive compound library, we identified gambogic acid and gambogenic acid as potential hit compounds. These proof-of-concept findings underscore the utility of our optimized multiplexed TR-FRET platform for large-scale screening to discover small molecule inhibitors that target the SMAD4-SMAD3-DNA complex as novel anti-TGF{beta} signaling agents.

cancer biology↗

Constitutively synergistic multiagent drug formulations targeting MERTK, FLT3, and BCL-2 for treatment of AML

Although high-dose, multi-agent chemotherapy has improved leukemia survival rates in recent years, treatment outcomes remain poor in high-risk subsets, including acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) in infants. Development of new, more effective therapies for these patients is therefore an urgent, unmet clinical need. To address this challenge, we developed a nanoscale combination drug formulation that exploits ectopic expression of MERTK tyrosine kinase and dependency on BCL-2 family proteins for leukemia cell survival in pediatric AML and MLL-rearranged precursor B-cell ALL (infant ALL). In a novel, high-throughput combination drug screen, the MERTK/FLT3 inhibitor MRX-2843 synergized with venetoclax and other BCL-2 family protein inhibitors to reduce AML cell density in vitro. Neural network models based on drug exposure and target gene expression were used to identify a classifier predictive of drug synergy in AML. To maximize the therapeutic potential of these findings, we developed a combination monovalent liposomal drug formulation that maintains ratiometric drug synergy in cell-free assays and following intracellular delivery. The translational potential of these nanoscale drug formulations was confirmed in a genotypically diverse set of primary AML patient samples and both the magnitude and frequency of synergistic responses were not only maintained but were improved following drug formulation. Together, these findings demonstrate a systematic, generalizable approach to combination drug screening, formulation, and development that maximizes therapeutic potential, was effectively applied to develop a novel nanoscale combination therapy for treatment of AML, and could be extended to other drug combinations or diseases in the future.

bioengineering↗

Screening and Development of Constitutively Synergistic Combination Drug Formulations for T Cell Acute Lymphoblastic Leukemia

Advances in multiagent chemotherapy have led to recent improvements in overall survival for patients with acute lymphoblastic leukemia (ALL); however, a significant fraction do not respond to frontline chemotherapy or later relapse with recurrent disease, after which long-term survival rates remain low. To address the challenge of developing new, effective treatment options for these patients, we conducted a series of high-throughput combination drug screens to identify chemotherapies that synergize in a lineage-specific manner with MRX-2843, a small molecule dual MERTK and FLT3 kinase inhibitor currently in clinical testing for treatment of relapsed/refractory leukemias and solid tumors. Using experimental and computational approaches, we found that MRX-2843 synergized strongly - and in a ratio-dependent manner - with vincristine chemotherapy to inhibit T-ALL cell expansion and, based on these findings, we developed multiagent lipid nanoparticle formulations of these drugs that not only constitutively maintained ratiometric drug synergy following T-ALL cell delivery, but also improved anti-leukemic activity following drug encapsulation. To determine the clinical relevance of these combination drug formulations and the therapeutic impact of ratiometric drug synergy, we compared the efficacy of lipid nanoparticles comprising synergistic, additive, and antagonistic ratios of MRX-2843 and vincristine, and observed that trends in in vitro synergy were directly recapitulated in primary T-ALL patient samples. Together, these findings present a systematic approach to high-throughput combination drug screening and multiagent drug delivery that maximizes the therapeutic potential of combined MRX-2843 and vincristine in T-ALL. This broadly generalizable approach could lead to the development of constitutively synergistic combination products for the treatment of cancer and other diseases.

bioengineering↗

Rapid determination of the wide dynamic range of SARS-CoV-2 Spike T cell responses in whole blood of vaccinated and naturally infected

BackgroundAntibodies and T cells cooperate to control virus infections. The definition of the correlates of protection necessary to manage the COVID-19 pandemic, require both immune parameters but the complexity of traditional tests limits virus-specific T cell measurements. MethodsWe test the sensitivity and performance of a simple and rapid SARS-CoV-2 Spike-specific T cell test based on stimulation of whole blood with peptides covering the SARS-CoV-2 Spike protein followed by cytokine (IFN-{gamma}, IL-2) measurement in different cohorts including BNT162b2 vaccinated (n=112; 201 samples), convalescent asymptomatic (n=62; 62 samples) and symptomatic (n=68; 115 samples) COVID-19 patients and SARS-CoV-1 convalescent individuals (n=12; 12 samples). ResultsThe sensitivity of the rapid cytokine whole blood test equates traditional methods of T cell analysis (ELISPOT, Activation Induced Markers). Utilizing this test we observed that Spike-specific T cells in vaccinated preferentially target the S2 region of Spike and that their mean magnitude is similar between them and SARS-CoV-2 convalescents at 3 months after vaccine or virus priming respectively. However, a wide heterogeneity of Spike-specific T cell magnitude characterizes the individual responses irrespective of the time of analysis. No correlation between neutralizing antibody levels and Spike-specific T cell magnitude were found. ConclusionsRapid measurement of cytokine production in whole blood after peptide activation revealed a wide dynamic range of Spike-specific T cell response after vaccination that cannot be predicted from neutralizing antibody quantities. Both Spike-specific humoral and cellular immunity should be tested after vaccination to define the correlates of protection necessary to evaluate current vaccine strategies.

immunology↗