Analyzer-to-Analyzer Variations in Assaying Ultralow Concentrated Biomarkers Associated with Neurodegenerative Diseases Using Immunomagnetic Reduction.

By utilizing a high-temperature superconducting quantum interference device (high-Tc SQUID) magnetometer, an alternating current (AC) magnetosusceptometer, referred to as an analyzer, was developed for ultrasensitive immunoassays. The analyzer has been applied to assay biomarkers in human plasma associated with Alzheimer's disease (AD) and Parkinson's disease (PD). The involved assay methodology is the so-called immunomagnetic reduction (IMR). Such an analyzer has been approved for clinical use in Taiwan and Europe. The mass production of the analyzer is needed for clinical utilities. The issue of exploring analyzer-to-analyzer variations in the performances becomes critical. Unfortunately, there is no standard characterization to determine the variations in performances among analyzers. In this study, key characterizations, such as output signal stability, signal-to-noise ratio, measured concentrations of a control sample, etc., are proposed. In total, three analyzers are characterized in this work. The detected biomarkers include amyloid peptides, total tau protein, phosphorylated tau protein, and α-synuclein protein for AD and PD. Through one-way ANOVA for any of the characterizations among the three analyzers, it was found that there was no significant difference in any of these characterizations among the analyzers (p > 0.05). Furthermore, the three analyzers are applied to assay biomolecules for AD and PD in reference samples. High correlations (r > 0.8) in measured concentrations of any of these biomarkers in reference samples were obtained among the three analyzers. The results demonstrate that the proposed characterizations are feasible for achieving consistent performance among high-Tc SQUID-based AC magnetosusceptometers for assaying biomolecules.

Development of a 36-Channel Instrument for Assaying Biomarkers of Ultralow Concentrations Utilizing Immunomagnetic Reduction.

With the demands of the high-throughput assay of biomarkers of ultralow concentrations in clinics, a 36-channel instrument utilizing immunomagnetic reduction (IMR) has been developed. The instrument involves the use of a high-T c superconducting-quantum-interference-device (SQUID) magnetometer to detect the signals due to the associations between target biomarker molecules and the antibody-functionalized magnetic nanoparticles in the reagent of IMR. In addition to illustrating the design and the measurements of the instrument, the assay characterizations for eight kinds of biomarkers related to neurodegenerative disease are investigated. Furthermore, the assay results among three independent instruments were compared. For an instrument, the channel-to-channel variations in measured concentrations of biomarkers are within a range of 2.09 to 5.62%. The assay accuracy was found to be from 99 to 103.7%. The p values in measured concentrations for any of the tested biomarkers were higher than 0.05 among the three instruments. The results demonstrate high throughput, high stability, and high consistency for the SQUID-IMR instruments.

Discovery of BPR1R024, an Orally Active and Selective CSF1R Inhibitor that Exhibits Antitumor and Immunomodulatory Activity in a Murine Colon Tumor Model.

Colony-stimulating factor-1 receptor (CSF1R) is implicated in tumor-associated macrophage (TAM) repolarization and has emerged as a promising target for cancer immunotherapy. Herein, we describe the discovery of orally active and selective CSF1R inhibitors by property-driven optimization of BPR1K871 (9), our clinical multitargeting kinase inhibitor. Molecular docking revealed an additional nonclassical hydrogen-bonding (NCHB) interaction between the unique 7-aminoquinazoline scaffold and the CSF1R hinge region, contributing to CSF1R potency enhancement. Structural studies of CSF1R and Aurora kinase B (AURB) demonstrated the differences in their back pockets, which inspired the use of a chain extension strategy to diminish the AURA/B activities. A lead compound BPR1R024 (12) exhibited potent CSF1R activity (IC50 = 0.53 nM) and specifically inhibited protumor M2-like macrophage survival with a minimal effect on antitumor M1-like macrophage growth. In vivo, oral administration of 12 mesylate delayed the MC38 murine colon tumor growth and reversed the immunosuppressive tumor microenvironment with the increased M1/M2 ratio.