Surface-Activated Ti3C2Tx Adsorption of Acetylene Black Coupled with Polyaniline as a Signal Tag for the Detection of the ESAT-6 Antigen of Mycobacterium tuberculosis

Early secretory antigenic target-6 (ESAT-6) is regarded as the most immunogenic protein produced by Mycobacterium tuberculosis, whose detection is of great clinical significance for tuberculosis diagnosis. However, the detection of the ESAT-6 antigen has been hampered by the expensive cost and complex experimental procedures, resulting in low sensitivity. Herein, we developed a titanium carbide (Ti3C2Tx)-based aptasensor for ESAT-6 detection utilizing a triple-signal amplification strategy. First, acetylene black (AB) was immobilized on Ti3C2Tx through a cross-linking reaction to form the Ti3C2Tx-AB-PAn nanocomposite. Meanwhile, AB served as a conductive bridge, and Ti3C2Tx can synergistically promote the electron transfer of PAn. Ti3C2Tx-AB-PAn exhibited outstanding conductivity, high electrochemical signals, and abundant sites for the loading of ESAT-6 binding aptamer II (EBA II) to form a novel signal tag. Second, N-CNTs were adsorbed on NiMn layered double hydride (NiMn LDH) nanoflowers to obtain NiMn LDH/N-CNTs, exhibiting excellent conductivity and preeminent stability to be used as electrode modification materials. Third, the biotinylated EBA (EBA I) was immobilized onto a streptavidin-coated sensing interface, forming an amplification platform for further signal enhancement. More importantly, as a result of the synergistic effect of the triple-signal amplification platform, the aptasensor exhibited a wide detection linear range from 10 fg mL-1 to 100 ng mL-1 and a detection limit of 4.07 fg mL-1 for ESAT-6. We envision that our aptasensor provides a way for the detection of ESAT-6 to assist in the diagnosis of tuberculosis.

Aggregation-induced enhancement of pyrene-based metal-organic framework as a new electrochemiluminescence emitter for ultrasensitive detection of sulfadimethoxine

In this study, a signal-on electrochemiluminescence (ECL) aptasensor for ultrasensitive detection of sulfadimethoxine (SDM) was constructed based on a competitive aptamer strategy. Specifically, cerium-metal-organic framework (Ce-MOF) with large specific surface area and excellent electrical conductivity was combined with gold nanoparticles (AuNPs) to form a substrate, followed by the immobilisation of double-stranded DNA (dsDNA) via AuN bonds. In the presence of SDM, the aptamer tended to form an aptamer-SDM complex, which caused dsDNA to dissociate. After release of the aptamer, the capture probe (CP) combined with the tracer label to enhance the ECL signal. As expected, the prepared sensor displayed an ideal linear response range from 10.0 fg mL-1 to 100 ng mL-1 with a limit of detection (LOD) of 1.28 fg mL-1 and successfully detected SDM in milk and quality control samples.

Immune profiling of patients with extranodal natural killer/T cell lymphoma treated with daratumumab

Natural killer/T cell lymphoma (NKTCL) is a highly aggressive, heterogeneous non-Hodgkin lymphoma resulting from malignant proliferation of cytotoxic natural killer (NK) or T cells. Previous studies demonstrated variable expression of CD38 on NKTCL tumors. Daratumumab, a human IgGκ monoclonal antibody targeting CD38 with a direct on-tumor and immunomodulatory mechanism of action, was hypothesized to be a novel therapeutic option for patients with relapsed or refractory (R/R) NKTCL. In the phase 2 NKT2001 study (ClinicalTrials.gov Identifier: NCT02927925) assessing the safety and efficacy of daratumumab, a suboptimal overall response rate was seen in R/R NKTCL patients. One patient, whose tumors did not express CD38, responded to treatment, suggesting that the immunomodulatory activities of daratumumab may be sufficient to confer clinical benefit. To understand the suboptimal response rate and short duration of response, we investigated the immune profile of NKTCL patients from NKT2001 in the context of daratumumab anti-tumor activity. Tumor tissue and whole blood were, respectively, analyzed for CD38 expression and patient immune landscapes, which were assessed via cytometry by time-of-flight (CyTOF), multiparameter flow cytometry (MPFC), clonal sequencing, and plasma Epstein-Barr virus (EBV)-DNA level measurements. Changes observed in the immune profiles of NKTCL patients from NKT2001, including differences in B and T cell populations between responders and nonresponders, suggest that modulation of the immune environment is crucial for daratumumab anti-tumor activities in NKTCL. In conclusion, these findings highlight that the clinical benefit of daratumumab in NKTCL may be enriched by B/T cell-related biomarkers.

"Gold-plated" PCN-222(Fe) and superconductive carbon black-based sandwich-type immunosensor for detecting CYFRA21-1

Cytokeratin 19 fragment antigen 21-1 (CYFRA21-1) is a protein fragment dissolved in the blood after apoptosis of lung epithelial cells, which is a predictive biomarker for the diagnosis of non-small cell lung cancer (NSCLC). Detection of serum CYFRA21-1 has a significant clinical value in diagnosis, monitoring and prognosis of NSCLC. Herein, a novel electrochemical immunosensor was constructed for the sensitive detection of CYFRA21-1. First, superconductive carbon black (KB) functionalized polyethyleneimine (PEI)-gold nanoparticles (AuNPs) were covered on the surface of methylene blue (MB) and used as substrate materials to immobilize the CYFRA21-1 antibody. Then, target CYFRA21-1 was successfully detected using an electrochemical immunosensor through specific recognition of antigen and antibody. The zirconium-based metal organic framework of PCN-222(Fe) with a large pore size and three-dimensional (3D) structure can absorb abundant AuNPs through strong electrostatic interaction, which enhances the conductive properties of PCN-222(Fe) and prevents the self-aggregation of AuNPs. However, PCN-222(Fe) with peroxidase-like activity can catalyze the generation of hydroxyl free radicals (˙OH) from H2O2, which oxidized MB, leading to a decrease in the current signal. The signal response to the degradation of MB was recorded using differential pulse voltammetry (DPV). This indirect method of immunosensor offered a new strategy to address the limitations imposed by the poor conductivity of PCN-222(Fe), further enabling the amplification of the signal through the oxidative degradation of MB. Compared with traditional electrochemical immunosensors, this method has the advantages of a stable current signal and good reproducibility, providing a promising reference for the broad application of PCN-222(Fe) in electrochemical biosensors.

Smartphone and paper-based device for glucose monitoring using acetylene black-hemin nanozyme as catalyst

Glucose management is an important part of disease control for diabetes patients, thus the development of a rapid and real-time point of care testing (POCT) device for monitoring blood glucose is of great significance. In this work, a paper-based analytical device (PAD) is constructed by combining acetylene black (AB)-hemin complex modified filter paper as sensing platform with a smartphone as signal detector. Large specific surface area of AB decreases the self-associate and aggregate of hemin in aqueous solution, resulting in improved peroxidase-like activity of hemin. Compared with graphene oxide supported hemin, AB-hemin exhibits superior signal response on paper. Glucose oxidase (GOx) catalyzes the conversion of blood glucose to hydrogen peroxide, and then AB-hemin complex catalyzes the oxidation of colorless 3,3',5,5'-tetramethylbenzidine (TMB) to blue TMB oxidized products (TMB⁺) in the presence of hydrogen peroxide, thus achieving the visual detection of blood glucose. In optimal conditions, PAD provides an applicable linear range from 0.2 mM to 30 mM and a low limit of detection (LOD) (0.06 mM). Notably, the detection accuracy of the developed paper-based sensor is in good agreement with that of the commercially available blood glucose meter (p > 0.05). Moreover, the proposed PAD presents high recoveries from 95.4% to 112% (RSD ≤ 3.2%), and therefore holds great potential for glucose monitoring and diabetes diagnosis.

A sandwich-type electrochemical immunosensor for sensitive detection of HER2 based on dual signal amplification of La-MOF-PbO2 and PEI-MoS2NFs composites

In recent decades, the incidence of breast cancer has increased year by year, posing a serious threat to human health and quality of life, and about 30% of breast cancer patients have human epidermal growth factor receptor 2 (HER2) overexpression. Therefore, HER2 has become an important biomarker and indicator for the clinical evaluation of breast cancer in diagnosis, prognosis and recurrence. In this work, polyethyleneimine functionalized MoS₂ nanoflowers (PEI-MoS₂NFs) with good electrical conductivity and abundant active binding sites were designed and employed as a sensing platform for immobilizing the primary antibody of HER2 (Ab₁). In addition, a La-MOF-PbO₂ composite with a large specific surface area and good conductivity was used to load lots of electroactive toluidine blue (TB) and the secondary antibody of HER2 (Ab₂) via gold nanoparticles (AuNPs) as the linker. Thus, the constructed sandwich-type electrochemical immunosensor was applied for sensitive detection of HER2, which showed a wide linear range from 100 fg mL^-1 to 10 μg mL^-1 with a lower limit of detection of 15.64 fg mL^-1. Therefore, the resulting immunosensor in this study would have a potential application in clinical bioanalysis.

An enzymatic activity regulation-based clusterzyme sensor array for high-throughput identification of heavy metal ions

The accurate identification and sensitive quantification of heavy metal ions are of great significance, considering that pose a serious threat to environment and human health. Most array-based sensing platforms, to date, utilize nanozymes as sensing elements, but few studies have explored the application of the peroxidase-like activity of clusterzymes in identification of multiple analytes. Herein, for the first time, we developed a clusterzyme sensor array utilizing gold nanoclusters (AuNCs) as sensing elements for five heavy metal ions identification including Hg²⁺, Pb²⁺, Cu²⁺, Cd²⁺ and Co²⁺. The heavy metal ions can differentially regulate the peroxidase-like activity of AuNCs, and that can be converted into colorimetric signals with 3,3',5,5'-tetramethylbenzidine (TMB) as the chromogenic substrate. Subsequently, the generated composite responses can be interpreted by combining pattern recognition algorithms. The developed clusterzyme sensor array can identify five heavy metal ions at concentrations as low as 0.5 μM and their multi-component mixtures. Especially, we demonstrated the successful identification of multiple heavy metal ions in tap water and traditional Chinese medicine, with an accuracy of 100% in blind test. This study provided a simple and effective method for identification and quantification of heavy metal ions, rendering a promising technique for environmental monitoring and drug safety assurance.

Kill two birds with one stone: Ratiometric sensing of phosphate via a single-component probe with fluorescence-scattering dual-signal response behavior

Ratiometric fluorescence sensors gain stronger anti-interference ability via self-calibration. Nevertheless, ratiometric analysis of phosphate (Pi) still faces problems such as complicated construction process of dual emission probes and possible interferences from outputting mono-category fluorescent signal. Herein, we propose a "kill two birds with one stone" strategy to address these challenges, by simply introducing a single-component probe, porphyrin paddlewheel framework-3 (PPF-3) nanosheets without modification, encapsulation or complex, to integrate fluorescence (FL)-second-order scattering (SOS) dual-signal for ratiometric detection of Pi. PPF-3 nanosheets are constructed by coordination of Co²⁺ with 5,10,15,20-tetrakis(4-carboxyl-phenyl)-porphyrin (TCPP) ligands, displaying weak FL and strong SOS, two different and independent signals. In the response system to Pi, Co²⁺ and TCPP serve as the recognition element and signal unit, respectively. After interacting with Pi, the high affinity for Co²⁺ makes Pi snatch Co²⁺ from the PPF-3 nanosheets, causing their structure disassembly (SOS decrease) and TCPP release (FL increase). Finally, the FL-SOS ratiometric platform is successfully employed to access Pi in real water samples. Synchronous collection of FL and SOS from the single-component probe provides a simpler and more efficient way on ratiometric sensor design as well as a new useful technique for monitoring target-induced aggregation and disaggregation behavior.

A Novel Signal-On Electrochemiluminescence Immunosensor for the Detection of NSCLC Antigen Biomarker Based on New Co-Reaction Accelerators

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer with substantial morbidity and mortality. Herein, a new signal-on electrochemiluminescence (ECL) immunosensor based on multiple amplification strategies is constructed for ultrasensitive detection of cytokeratin 19 fragment antigen 21-1 (CYFRA21-1) biomarker related to NSCLC. Polyethyleneimine (PEI) functionalized MXene is decorated with NiMn layer double hydroxide (NiMn LDH) to form MXene-PEI-NiMn LDH composite. Specially, the La-MOF@ZIF-67 bimetallic organic framework (named as LZBM) and MXene-PEI-NiMn LDH both served as coreaction accelerators to improve the ECL emission of the luminol-H₂ O₂ system. To be specific, Au nanoparticles (AuNPs) coated MXene-PEI-NiMn LDH is applied to immobilize primary CYFRA21-1 antibody (Ab₁ ), while AuNPs decorated LZBM was used for the loading of luminol and secondary CYFRA21-1 antibody (Ab₂ ) to form tracer label. Therefore, the ECL signal of the sandwich-type immunosensor is significantly enhanced due to the high loading capability for luminol and the synergistic catalytic ability for the decomposition of H₂ O₂ into reactive oxygen species (ROS). Under the optimal experimental conditions, the ECL immunosensor exhibited good analytical performances for CYFRA21-1 detection with a wide linear range (100 fg mL^-1 -100 ng mL^-1 ) and a low limit of detection (85.20 fg mL^-1 ), providing a promising method for early diagnosis of NSCLC.

Quadruple analyte responsive platform: Point-of-care testing and multi-coding logic computation based on metal ions recognition and selective response

While it is recognized that instrumentation techniques can provide precise and sensitive solutions to heavy metal ion monitoring, it remains challenging to transform laboratory testing into a convenient, on-site, and quantitative sensing platform for point-of-care testing (POCT) in a resource-constrained setting. To address these limitations, an affordable and user-friendly colorimetric POCT sensing system is proposed here for selectively monitoring four metal ions (Fe³⁺, Co²⁺, Pb²⁺, and Cd²⁺) based on the sulfur quantum dots (S dots). Quadruple distinct visual signals (green, brown, precipitation, and bright yellow) are presented on the fabricated paper-based analytical devices (PADs) when mixing S dots and metal ions. The high-quality photographs of the PADs are captured by a scanner, while a smartphone App converts visual signals to HSV values. The quantitative analysis relies on the digital colorimetric reading, and the limits of detection are 0.59, 0.47, 0.82, and 0.53 μM for Fe³⁺, Co²⁺, Cd²⁺, and Pb²⁺, respectively. This metal ions-responsive platform is engineered as a smart strategy for multiple logic operations (YES, NOT, AND, INHIBIT, and NOR) by integrating multi-responsive blocks into the S dots with encoded patterns, which improves the computing capability. Accordingly, this strategy demonstrates its potential for on-site environmental testing and sophisticated molecular computation.

Rational design of a fluorescent probe for specific sensing of hydrogen peroxide/glucose and intracellular imaging applications

A new type of dye with advantages of high selectivity and sensitivity is formed by using the strategy of hybridization between the luminescent unit and recognition unit. Based on this strategy, we exploit a novel dye bonding the benzopyrylium salt as a luminescent unit and phenylboronate group as a response site, which is served as a fluorescent probe 1 for specific recognition of hydrogen peroxide in biological application. Probe 1 employs a unique recognition switch, phenylboronate unit, to"turn-on"a highly specific and rapid fluorescence response toward hydrogen peroxide combined with the 1,6-rearrangement elimination reaction strategy. Meanwhile, probe 1 has the ability to glucose assay by taking advantage of glucose oxidase/glucose enzymatic reaction. What's more, the probe 1 is capable of tracking endogenous hydrogen peroxide in living cells and intracellular imaging. Therefore, the newly developed bioprobe 1 is expected to be used to monitor hydrogen peroxide and glucose levels in complex organisms.

A dual-response fluorescent probe for discriminative sensing of hydrazine and bisulfite as well as intracellular imaging with different emission

Bisulfite and hydrazine are harmful to the environment safety and human health. Therefore, it is of great value to develop a smart fluorescent probe with high selectivity for detection of bisulfite and hydrazine. In our report, a dual-response fluorescent probe EDBI with high selectivity, rapid response, and low detection limit for discriminative determination HSO₃^- and N₂H₄ was exploited. The probe EDBI is capable of distinctive sensing HSO₃^- and N₂H₄ based on nucleophilic addition reactions by taking advantage of ratiometric fluorescence and fluorescence "on-off" mode, respectively. The dual-responses behaviors of probe EDBI toward HSO₃^- and N₂H₄ were attribute to different reaction sites, which it has been confirmed by HRMS. More importantly, cytotoxicity experiment authenticated that probe possesses low toxicity and good penetration. The probe EDBI with excellent performance, it was successfully employed to distinguishable sense HSO₃^- and N₂H₄ in living cells by diverse channel patterns. Therefore, this simple dual-response fluorescence probe is expected to be used for real-time monitoring bisulfite and hydrazine in biological samples.

Updated analysis with longer follow up of a phase 2a study evaluating erdafitinib in Asian patients (pts) with advanced cholangiocarcinoma (CCA) and fibroblast growth factor receptor (FGFR) alterations

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Background: Pts with CCA progressing after first-line therapy have limited treatment options. We report an updated analysis of the ongoing LUC2001 open-label, multicenter, phase 2a study (NCT02699606) investigating the efficacy and safety of erdafitinib in Asian pts with advanced CCA and FGFR alterations who progressed after ≥1 prior systemic treatment. Methods: Eligible adults (aged ≥18 years) received erdafitinib 8 mg once daily (QD) with pharmacodynamically guided up-titration to 9 mg QD. The primary endpoint was objective response rate (ORR; RECIST 1.1); secondary endpoints included best overall response (BOR), disease control rate (DCR), duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety. Survival estimates were determined by the Kaplan–Meier method. Results: Of 232 patients with CCA who underwent molecular screening, 39 (16.8%) had FGFR alterations (21 [9.1%] fusions and 19 [8.2%] mutations). Overall, 22 (9.5%) eligible pts (median age, 52 [range, 29–69] years) were enrolled and received treatment. Median follow-up was 22.4 (range, 2.3–47.0) months; median treatment duration was 6.2 (range, 1.5–35.6) months. All 22 pts received ≥1 line of prior systemic therapy and 12 (55.0%) pts had ≥2 prior lines of therapy. The ORR was 40.9% (95% CI, 20.7%–63.6%) and median time to response was 1.8 (range, 1.5–5.6) months. Median DOR was 7.3 (95% CI, 3.7–17.5) months, median PFS was 5.6 (95% CI, 3.6–12.7) months, and median OS was 40.2 (95% CI: 9.9–not estimable) months (Table). Responses were observed in 8/14 pts with FGFR fusions and 1/8 pts with FGFR mutations and in pts who received 1 or ≥2 prior lines of therapy. All 22 pts had ≥1 treatment-emergent adverse event (TEAE), the most common being dry mouth (15/22 [68.2%]) and stomatitis (14/22 [63.6%]). Grade ≥3 TEAEs occurred in 15/22 (68.2%) pts (11/22 [50.0%] were treatment related), of which the most common were stomatitis (3/22 [13.6%]) and alanine aminotransferase (ALT) increased (3/22 [13.6%]); 11/22 (50.0%) pts had ≥1 serious TEAE (1/22 [4.5%] pts had a serious treatment-related TEAE). A TEAE leading to death occurred in 1 patient (sepsis; not treatment-related). Conclusions: Asian pts with advanced CCA and FGFR alterations treated with erdafitinib had durable efficacy and a manageable safety profile, supporting the earlier findings of erdafitinib benefit in this population. Clinical trial information: NCT02699606. [Table: see text]

An optical sensing system with ratiometric and turn-off dual-mode of CDs@MnO2 nanosheets for the determination of H2O2 and glucose based on a combination of first-order scattering, fluorescence, and second-order scattering

The optical sensor with ratiometric and turn-off dual modes is constructed to detect H₂O₂ and glucose based on blue fluorescent carbon dots (CDs) and MnO₂ nanosheets with great ability of fluorescence quenching and scattering. Employing CDs@MnO₂ nanosheets nanocomposite as the probe, H₂O₂ is detected by simultaneously collecting first-order scattering (FOS, 353.5 nm), fluorescence (440 nm), and second-order scattering (SOS, 710 nm) under the excitation of 350 nm. H₂O₂ with strong oxidation property can etch the lamellar structure of MnO₂ nanosheets into nano-fragments, which made the fluorescence of CDs in the system recover and the scattering intensity (FOS and SOS) of the system decrease significantly. Therefore, the optical sensor combined FOS and fluorescence signals in ratiometric mode, and SOS signal in turn-off mode to realize sensitive determination of H₂O₂. The linear ranges of ratiometric mode and turn-off mode for H₂O₂ detection were 0.2-40 and 0.2-15 μM, respectively. And the limits of detection (LODs) of two modes were 73 and 104 nM, respectively. Furthermore, the sensor was also successfully applied to the detection of glucose which can react to produce H₂O₂. Satisfactorily, the LODs of this sensor for glucose detection were 95 and 113 nM for ratiometric mode and turn-off mode, respectively. This work not only provides a new method for the accurate detection of H₂O₂ and glucose, but also extends a new idea for the study of the combination of scattering and fluorescence.

'Plug and play' microelectrode assisted with Y-motif-mediated primer-free cyclic signal amplification for sensitive quantitation of DNA methyltransferase activity

DNA methyltransferase (MTase), modulating the level of genomic DNA methylation, harbors both a pharmacological target for clinical therapy and a potential biomarker for genetic disorders and tumorigenesis. Typical homogeneous electrochemical approaches, employing solution phase probes, have been considered simple, efficient, and economical method, yet these architectures usually require electroactive molecules labeling, rely on weak electrostatic adsorption interaction, and possess low sensitivity. For circumventing the above drawbacks, herein, we devise a 'plug and play' microelectrode featuring microminiaturization, rapid response time and enhanced mass transport to quantify MTase activity through monitoring the variation of diffusion current of methylene blue (MB) induced by the less-mobile G-quadruplex framework. By coupling the unique signal-transduction approach with Y-motif-mediated primer-free cyclic signal amplification (YPCSA), the miniaturized biosensor possesses low detection limit (down to 2.5 × 10^-4 U mL^-1), high specificity, good stability and satisfying reusability, and has been successfully applied to the screening of MTase inhibitors, holding great potential in clinical diagnosis and pharmacological research.

Abstract 1023: Understanding the anti-tumor activities of daratumumab in natural killer/T cell lymphoma (NKTCL)

Background: NKTCL is an aggressive and heterogenous type of non-Hodgkin's lymphoma that is characterized by malignant proliferation of cytotoxic natural killer (NK) or T cells and is associated with Epstein-Barr virus (EBV). Previous studies have shown that NKTCL tumors variably express CD38. Thus daratumumab (DARA), a human IgGκ monoclonal antibody targeting CD38 with direct on-tumor and immunomodulatory mechanism of action, was hypothesized to be a novel therapeutic option for patients with relapsed or refractory (R/R) NKTCL. The open-label, single-arm, multicenter, phase 2 study NKT2001 (NCT02927925) assessed the safety and efficacy of DARA in patients with R/R NKTCL, with an overall response rate of 25% and a 55 day median duration of response (DOR). Baseline serum EBV and CD38 expression levels did not show a clear correlation with clinical response. One NKTCL patient whose tumors did not express CD38 responded to treatment, suggesting that the immunomodulatory activities of DARA may be sufficient to confer clinical benefit. To understand the suboptimal response rate and short DOR, we interrogated the environmental, viral, and immune profile of NKTCL patients from NKT2001 in the context of DARA anti-tumor activity.

Methods: CD38 expression was assessed by immunohistochemistry. Patient immune landscapes were assessed by cytometry by time-of-flight (CyTOF), multi-parameter flow cytometry (MPFC), clonal sequencing, and serum EBV level measurements.

Results: Based on CyTOF and MPFC, high levels of baseline naive CD38- B cells with low percentage of CD38+ B cell populations (including transitional B, plasmablast, and plasma cells) were found to be significantly correlated with clinical response. However, subsequent B and T cell receptor sequencing did not detect clear relationships between pre-existing or treatment-emergent EBV-related B or T cell clones with clinical response. CyTOF analyses demonstrated a reduction of CD38+ NK cells, NK T cells, myeloid-derived suppressor cells (MDSCs), and regulatory T cells (Tregs) with DARA treatment. Nevertheless, persisting NK and NK T cells maintained cell surface markers indicative of functionality. Total Tregs and MDSCs levels did not change despite diminished CD38 expression, suggesting that DARA did not reverse the immune suppression mediated by Tregs or MDSCs. In contrast, there was a trend towards a decrease in CD4/CD8 ratio from baseline in responders but not in nonresponders, suggesting modulation of the immune environment is crucial for DARA anti-tumor activities in NKTCL.

Conclusion: These results demonstrate that DARA can lead to clinical response in patients with NKTCL by modulating the immune environment.

Citation Format: Tianyuan Zhou, Min Qing, Yann Abraham, Tatiana Perova, Cheryl Sweeney, Maria Krevvata. Understanding the anti-tumor activities of daratumumab in natural killer/T cell lymphoma (NKTCL) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1023.

Universal and Programmable Rolling Circle Amplification-CRISPR/Cas12a-Mediated Immobilization-Free Electrochemical Biosensor

The development of a sensing platform with high sensitivity and specificity, especially programmability and universal applicability, for the detection of clinically relevant molecules is highly valuable for disease monitoring and confirmation but remains a challenge. Here, for the first time, we introduce the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas system into an immobilization-free electrochemical biosensing platform for sensitively and specifically detecting the disease-related nucleic acids and small molecules. In this strategy, a modular rolling circle amplification (RCA) is designed to transform and amplify the target recognition event into the universal trigger DNA strand that is used as the trigger to activate the deoxyribonuclease activity of CRISPR/Cas12a for further signal amplification. The cleavage of the target-activated blocker probe allows the methylene blue-labeled reporter probes to be captured by the reduced graphene oxide-modified electrode, leading to an obviously increased electrochemical signal. We only need to simply tune the sequence for target recognition in RCA components, and this strategy can be flexibly applied to the highly sensitive and specific detection of microRNAs, Parvovirus B19 DNA, and adenosine-5'-triphosphate and the calculated limit of detection is 0.83 aM, 0.52 aM, and 0.46 pM, respectively. In addition, we construct DNA logic circuits (YES, NOT, OR, AND) of DNA inputs to experimentally demonstrate the modularity and programmability of the stimuli-responsive RCA-CRISPR/Cas12a system. This work broadens the application of the CRISPR/Cas12a system to the immobilization-free electrochemical biosensing platform and provides a new thinking for developing a robust tool for clinical diagnosis.

Spatially localized amplification reaction with accelerated target conversion for sensitive microRNA detection

Herein, we construct an ingenious spatially localized amplification reaction (SLAR) by colocalizing the entropy-driven reaction (EDR) in a nanometer space, which greatly accelerates target conversion and realizes the sensitive detection of microRNA-21 (miRNA-21). A large number of EDR complex are hybridized with the prefabricated DNA scaffold via a DNA self-assembly strategy to form the SLAR nanoprobe. Target miRNA-21 triggers interval EDR along the long DNA scaffold, resulting in fluorescence recovery with high signal gain because of the fast release of reporter. Compared with reactions with diffusible components, spatial arrangement of all components of EDR on a nanoscale scaffold can increase the local concentration of reactants, accelerating the interaction between adjacent components, and can also avoid the influence of stochastic diffusion to reduce the unintentional binding interaction between further separated components. Therefore, this SLAR assay displayed an excellent analytical performance for miRNA-21 detection with a detection limit of 6 pM and showed good specificity in distinguishing miRNA-21 from similar miRNAs. In addition, the proposed assay has been experimentally demonstrated for estimation of miRNA-21 in MCF-7 and HeLa cells lysates, which exhibited great promise in the sensitive detection of biomarkers in early diagnosis.

Daratumumab monotherapy for patients with relapsed or refractory natural killer/T-cell lymphoma, nasal type: an open-label, single-arm, multicenter, phase 2 study

Background

Natural killer/T-cell lymphoma (NKTCL) is a disease with limited treatment options and poor outcomes. Daratumumab monotherapy demonstrated clinical activity in a single-patient case report. We present data from the primary analysis of a phase 2 study of daratumumab monotherapy in relapsed or refractory (R/R) NKTCL.

Methods

This phase 2 study with Simon’s two-stage design evaluated daratumumab in patients with histologically confirmed extranodal NKTCL, nasal type, per WHO classification that was refractory to or relapsed after ≥ 1 line of chemotherapy, who were not candidates for other treatment modalities. All patients received daratumumab 16 mg/kg intravenously once weekly for Cycles 1 and 2, every other week for Cycles 3 through 6, and every 4 weeks thereafter until progression or unacceptable toxicity; all cycles were 28 days. The primary end point was objective response rate (ORR) based on blinded independent central review per Revised Criteria for Response Assessment of Hodgkin and non-Hodgkin Lymphoma (Lugano classification).

Results

In total, 32 Asian patients received daratumumab. The ORR was 25.0% (95% confidence interval [CI] 11.5–43.4); all 8 responders had a partial response; and the median duration of response was 55.0 days (95% CI 29–339). At 10.2 months of median follow-up, median progression-free survival (PFS) was 53.0 days (95% CI 43–106); the 4-month PFS rate was 13.0%. Median overall survival (OS) was 141.0 days (95% CI 94–438); the 6-month OS rate was 42.9%. Nineteen (59.4%) patients had grade 3/4 treatment-emergent adverse events (TEAEs); the most common was thrombocytopenia (25.0%; n = 8). TEAEs leading to death occurred in 4 patients (death, respiratory failure, septic shock, and pneumonia); all were unrelated to daratumumab.

Conclusions

In patients with R/R NKTCL, daratumumab monotherapy was well tolerated with no new safety concerns and achieved an ORR of 25.0%. However, no patients achieved complete response, and duration of response was short.

Trial registration ClinicalTrials.gov, NCT02927925. Registered 7 October 2016.

Smartphones and Test Paper-Assisted Ratiometric Fluorescent Sensors for Semi-Quantitative and Visual Assay of Tetracycline Based on the Target-Induced Synergistic Effect of Antenna Effect and Inner Filter Effect

Development of selective and sensitive methods for on-site assay of tetracycline (TC) is of great significance for public health and food safety. Herein, a valid ratiometric fluorescence strategy using g-C₃N₄ nanosheets coupled with Eu³⁺ is designed for the assay of TC. In this strategy, both Eu³⁺ and g-C₃N₄ nanosheets serve as the recognition units of TC. The blue fluorescence of g-C₃N₄ nanosheets can be quenched by TC via the inner filter effect (IFE); meanwhile, the red fluorescence of Eu³⁺ can be enhanced by TC through the antenna effect (AE). The synergistic effect of AE and IFE caused by TC makes the developed ratiometric fluorescent sensor display a wide linear range for TC from 0.25 to 80 μM with a detection limit of 6.5 nM and a significant fluorescence color evolution from blue to red. Given its simplicity, free-label, excellent selectivity, high sensitivity, and recognizable color change, point-of-care testing systems, including smartphones and test paper-based assays, are developed for the visual sensing of TC. The integration of smartphones and test paper on a ratiometric fluorescent sensor greatly reduces the detection cost and time, providing a promising method for the qualitative discernment and semi-quantitative assay of TC on-site. Moreover, the potential application of the approach is also verified by detecting TC in milk.

Analysis for 208 children with psoriasis vulgaris

OBJECTIVES

Psoriasis is a chronic inflammatory skin disease that affects adults and children. The most common subtype is psoriasis vulgaris. This article analyzes the characteristics and clinical features of children with psoriasis vulgaris to strengthen the understanding, treatment, and management for children with psoriasis.

METHODS

A total of 208 children with psoriasis vulgaris, who were first admitted to the Department of Dermatology, Xiangya Hospital, Central South University from October 2012 to December 2018, were retrospectively analyzed. Their clinical characteristics, results of laboratory examination, treatment options and efficacy were summarized.

RESULTS

The age of the 208 children with psoriasis vulgaris was (11.19±3.97) years old, the peak incidence was 12 years old, the disease duration was (27.46±31.30) months, and the male-female ratio was 1∶0.96. The most common site of the first attack was the scalp (37.98%), followed by the trunk (26.44%) and the limbs (22.12%). The causes leading to exacerbation were more common in infections and diets. There were 33 patients (15.87%) with a family history of psoriasis, showing the higher score of Psoriasis Area and Severity Index (PASI) and the higher Dermatological Quality of Life Index (DLQI) (both P<0.05). In all patients, 29 cases (13.94%) were overweight, 19 cases (9.14%) were obese, and the rate of overweight and obesity in children with psoriasis vulgaris was higher than that of normal children in China. In the laboratory test, the serum levels of 25-hydroxyvitamin D (25-OH-VD) were decreased in most patients (47.5%), and the serum 25-OH-VD levels were found to be moderately negatively correlated with PASI score (P<0.05). The score of DLQI in the patient was 5.56±3.57, the score of PASI was 7.25±6.83, and they were positively correlated (r=0.409, P<0.001). In most patients (72.11%), the severity of the disease was mild to moderate. Their treatment was often dominated by topical drugs and Chinese patent medicine (65.67%). Retinoids showed a good effect on children. Cyclosporine and methotrexate were effective in more severe cases.

CONCLUSIONS

Children with psoriasis vulgaris are mainly caused by infection and diet. Patients with family history have more serious illness, lower quality of life, and are more likely to have metabolic abnormalities such as overweight and obesity. The serum 25-OH-VD levels in children with psoriasis vulgaris are negatively correlated with the score of PASI.

Updated results of a phase IIa study to evaluate the clinical efficacy and safety of erdafitinib in Asian advanced cholangiocarcinoma (CCA) patients with FGFR alterations

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Background: Patients (pts) with advanced CCA who progressed on or after first line chemotherapy have no approved treatment options. Fibroblast growth factor receptor (FGFR) gene alterations are observed in many tumor types including 14-17% in CCA. Erdafitinib, an orally bioavailable, selective pan-FGFR kinase inhibitor, has shown clinical activity against solid tumors with FGFR alterations. Methods: LUC2001 is an open-label, multicenter, Ph2a study in advanced CCA pts with FGFR alterations (FoundationOne), who progressed after ≥ 1 prior treatment. The primary endpoint is objective response rate (ORR; RECIST 1.1). The secondary endpoints are disease control rate (DCR), progression free survival (PFS), duration of response (DOR), safety and pharmacokinetics (PK). Disease is evaluated every 8 weeks until disease progression (PD). Results: As of 3 Dec 2018, 222 CCA pts were molecularly screened; 34 had FGFR alterations, of whom 14 (8 FGFR2 fusion, 3 FGFR2 mutation, 1 FGFR3 fusion, 2 FGFR3 mutation) were dosed 8 mg once daily with up titration option. Median age was 51.5 years. 13/14 and 12/14 pts had prior platinum or gemcitabine based therapy respectively, 7/14 pts got re-treated with platinum or gemcitabine based therapy, and 9/14 pts had ≥2 prior lines of therapy. Median number of treatment cycles was 5.0 (range: 1; 22) and treatment duration was 4.83 (range: 0.5; 20.3) months. In 12 evaluable pts, there were 6 confirmed partial response (PR), 4 stable disease (SD) and 2 PD; ORR (CR+PR) was 6/12 (50.0%), DCR (CR+PR+uCR+uPR+SD) was 10/12 (83.3%); median DOR was 6.83 months (95% CI: 3.65; 12.16); median PFS was 5.59 months (95% CI: 1.87, 13.67). In 10 evaluable FGFR2+ pts, ORR was 6/10 (60.0%); DCR was 10/10(100%); median PFS was 12.35 months (95% CI: 3.15, 19.38). The most common TEAEs ( > 30%) were hyperphosphatemia, dry mouth, stomatitis, and dry skin. 9 pts had ≥ Grade 3 AEs (8 Grade 3,1 Grade 5), of which 7 drug related. TEAE led to treatment 1 discontinuation, 6 dose reductions and 1 death (not drug related). The results of PK and PK/PD relationship were consistent with other erdafitinib studies in different ethnic background pts. Conclusions: Asian advanced CCA pts with FGFR alterations treated with erdafitinib had encouraging efficacy and acceptable safety profile similar to experience in other tumor types and populations. Clinical trial information: NCT02699606.

Concordance of immune checkpoints within tumor immune contexture and their prognostic significance in gastric cancer

Checkpoint blockade therapy has emerged as a novel approach for cancer immunotherapy in several malignancies. However, patient prognosis and disease progression relevant to immune checkpoints in gastric tumor microenvironment are not defined. This study aims to investigate the expression and prognostic significance of immune checkpoints within gastric cancer. In the study, a cohort of 398 cancer tissues from stage I to IV gastric cancer patients were assessed for programmed cell death 1 ligand 1 (PD-L1) expression and tumor-infiltrating lymphocyte (TIL) infiltration using immunohistochemistry to ascertain their survival correlation. The data revealed that higher TIL density correlated with less risk of disease progression, and exhibited survival benefits in gastric cancer patients, and PD-L1 positivity showed a significant association with the presence of high TIL infiltration. Furthermore, real-time quantitative polymerase chain reaction was performed to detect expression of multiple immune checkpoints with the relation to clinical outcome in 139 samples randomly selected from the same cohort, and higher messenger RNA levels of most immune checkpoints were associated with favorable outcome, while consistently showing a positive correlation with interferon gamma levels. In situ hybridization was used to determine the localization of Epstein-Barr virus (EBV) in 97 specimens, and showed EBV-positive gastric cancer samples correlated with PD-L1 expression and increased TIL density. These results suggest that induction of immune checkpoint within gastric cancer patients reflects a high immune infiltration density, especially in those with EBV-associated gastric cancer, which may direct patient selection for checkpoint blockade therapy.

The C-terminal helical domain of dengue virus precursor membrane protein is involved in virus assembly and entry

The role of the α-helical domain (MH) of dengue virus (DENV) precursor membrane protein in replication was investigated by site-directed mutagenesis. Proline substitutions of three residues (120, 123 and 127) at the C-terminus, but not those at the N-terminus of MH domain, reduced the virus-like particles of DENV1, DENV2 and DENV4 detected in supernatants. In a DENV2 replicon trans-packaging system, these three mutations suppressed particles detected; two of them (I123P and V127P) also affected viral entry. In the context of DENV2 genome-length RNA, all three mutations reduced virion assembly and virus spreading in cell culture. Analysis of revertants showed that mutation A120P could partially support viral infection cycle; in contrast, mutations I123P and V127P were lethal, and adaptations of I123P→I123L and V127P→V127L were required to restore the viral infection cycle. These findings demonstrate that the C-terminus of the MH domain is involved in both assembly and entry of DENV.

Antiviral effect of interferon lambda against West Nile virus

Type III interferons (IFN), IFN-lambda or IL-28/29, are new members of the IFN super-family. Except for using distinct receptors, type I and type III IFNs share the same major post receptor signaling components to activate the transcription of a similar set of IFN-stimulated genes (ISGs). To examine the antiviral effects of the new type IFNs against West Nile virus (WNV), we compared the antiviral effects of IFN-alpha and IFN-lambda on WNV virus-like particle (VLP) infection and replicon replication in Huh7.5 and Hela cells. The results revealed that (i) both types of IFNs could efficiently prevent the WNV infection, but IFN-alpha demonstrated a stronger antiviral efficacy; (ii) WNV genome replication in VLP-infected cells and replicon-containing cell lines could only be inhibited by IFN-alpha, but not IFN-lambda; (iii) in agreement with the observed antiviral effects, only IFN-lambda-induced activation of JAK-STAT signaling pathway and induction of ISG expression were completely inhibited in WNV replicon-containing cell lines, but IFN-alpha signal transduction was either unaffected or only partially inhibited in Huh7.5 or Hela cells by the virus. Hence, the differential inhibition of WNV on IFN-alpha and IFN-lambda signal transduction implies that the receptors of the two types of IFNs, but not the common post receptor signaling components, could be selectively targeted either directly by WNV nonstructural proteins or indirectly by the cellular responses induced by the virus infection to inhibit the signal transduction of the cytokines.

Moderate hypothermia during cardiopulmonary bypass reduces myocardial cell damage and myocardial cell death related to cardiac surgery

OBJECTIVES

The goal of this study was to test the hypothesis that moderate hypothermia during cardiopulmonary bypass (CPB) provides myocardial protection by enhancing intra-myocardial anti-inflammatory cytokine balance.

BACKGROUND

Moderate hypothermia during experimental CPB stimulates production of interleukin-10 (IL10) and blunts release of tumor necrosis factor-alpha (TNFalpha).

METHODS

Twelve young pigs were assigned to a temperature (T degrees ) regimen during CPB: moderate hypothermia (T degrees : 28 degrees C; n = 6) and normothermia (T degrees : 37 degrees C; n = 6). Intra-myocardial TNFalpha- and IL10-messenger RNA were detected by competitive reverse transcriptase polymerase chain reaction and quantification of cytokine synthesis by Western blot. Levels of cardiac troponin I (cTnI) in cardiac lymph and in arterial and coronary venous blood were examined during and after CPB. Myocardial cell damage was assessed by histologic and ultrastructural anomalies of tissue probes taken 6 h after CPB.

RESULTS

Synthesis of IL10 was significantly higher, while that of TNFalpha was significantly lower, in pigs that were in moderate hypothermia during surgery than in the others. In contrast with normothermia, moderate hypothermia was also associated with significantly lower cumulative cardiac lymphatic flow during and after CPB, significantly lower lymphatic cTnI concentrations after CPB, significantly lower percentages of myocardial cell necrosis and a significantly lower score of ultrastructural anomalies of myocardial cells. While the percentage of apoptotic cells was not different between groups, the apoptosis/necrosis ratio tended to be higher in animals that were in moderate hypothermia during surgery. In all animals, TNFalpha synthesis correlated positively while IL10 production correlated negatively with necrosis and total cell death, respectively.

CONCLUSIONS

Our results suggest that moderate hypothermia during CPB provides myocardial protection by enhancing intra-myocardial anti-inflammatory cytokine balance.

Influence of temperature during cardiopulmonary bypass on leukocyte activation, cytokine balance, and post-operative organ damage

This study examined the hypothesis that core temperature (T(o)) during cardiopulmonary bypass (CPB) influences the perioperative systemic inflammatory response and post-operative organ damage. Twenty-four pigs were assigned to a T(o) regimen during CPB: normothermia (T(o) 37 degrees C; n = 8), moderate hypothermia (T(o) 28 degrees C; n = 8), or deep hypothermia (T(o) 20 degrees C; n = 8). Perioperative leukocyte activation, endotoxin release, and production of tumor necrosis factor-alpha (TNFalpha) and interleukin-10 (IL10) were examined with regard to post-operative organ damage, which was scored at histological examination of tissue probes of heart, lungs, liver, kidney, and ileum, taken 6 h after CPB. Total blood leukocyte count and TNFalpha plasma levels during CPB were significantly lower and IL10 levels were significantly higher in the moderate hypothermic group than in both other groups. Elastase activity, leukotriene B4-, and endotoxin levels were not affected by T(o) regimen. Moderate hypothermia was associated with the lowest histological organ damage score and normothermia with the highest. In all animals organ damage score for heart, lungs, and kidneys correlated significantly with TNFalpha levels at the end of CPB. Our data demonstrate a clear relationship between TNFalpha production during cardiac operations and post-operative multiple-organ damage. Moderate hypothermia, by stimulating IL10 synthesis and suppressing TNFalpha production during CPB, might provide organ protection.

Identification of 10 novel snoRNA gene clusters from Arabidopsis thaliana

Ten novel small nucleolar RNA (snoRNA) gene clusters, consisting of two or three snoRNA genes, respectively, were identified from Arabidopsis thaliana. Twelve of the 25 snoRNA genes in these clusters are homologous to those of yeast and mammals according to the conserved antisense sequences that guide 2'-O-ribose methylation of rRNA. The remaining 13 snoRNA genes, including two 5.8S rRNA methylation guides, are new genes identified from A.thaliana. Interestingly, seven methylated nucleotides, predicted by novel snoRNAs Z41a-Z46, are methylated neither in yeast nor in vertebrates. Using primer extension at low dNTP concentration the six methylation sites were determined as expected. These snoRNAs were recognized as specific guides for 2'-O:-ribose methylation of plant rRNAs. Z42, however, did not guide the expected methylation of 25S rRNA in our assay. Thus, its function remains to be elucidated. The intergenic spacers of the gene clusters are rich in uridine (up to 40%) and most of them range in size from 35 to 100 nt. Lack of a conserved promoter element in each spacer and the determination of polycistronic transcription from a cluster by RT-PCR assay suggest that the snoRNAs encoded in the clusters are transcribed as a polycistron under an upstream promoter, and individual snoRNAs are released after processing of the precursor. Numerous snoRNA gene clusters identified from A.thaliana and other organisms suggest that the snoRNA gene cluster is an ancient gene organization existing abundantly in plants.

Systemic inflammatory response to cardiac surgery: does female sex really protect?

Sex hormones have important interactions with the immune system and modulate the inflammatory response. In this regard, oestrogen inhibits the transcription of proinflammatory cytokines and confers tissue protection in experimental models. On the basis of this evidence, Trotter et al. in this issue of Critical Care addressed the question of whether, in children, female sex would protect against the deleterious effects of cardiac operations with cardiopulmonary bypass by providing a favourable anti-inflammatory cytokine balance. The observations made in that study suggest sex-related immunomodulation and organ protection during cardiac surgery in the paediatric population. Prospective trials conducted in large series, including sex hormone determination in neonates, infants and children with congenital cardiac defects, are necessary to test this hypothesis. The verification of sex-related intraoperative organ protection would provide new opportunities for preventing the uncontrolled systemic inflammatory response that may occur during cardiac surgery.

Cannulation of the cardiac lymphatic system in swine

OBJECTIVE

Cardiac lymph is the most direct medium for analyzing metabological changes in the myocardial cell. Currently, dogs are the animals used for investigation of myocardial lymphatic function. However, questions arise when comparing and interpreting the human system to the experimental model, since the dog coronary anatomy is different from human anatomy and pulmonary lymph contamination is found in up to 81% of the cases. Swine, having similar coronary anatomy to humans, are a proven model for cardiovascular research. The purpose of this study was to investigate the cardiac lymphatic anatomy of the swine and to develop a reliable cannulation technique to collect the lymph.

METHODS AND RESULTS

The lymphatic anatomy of 60 pigs was studied and classified and a new technique for lymphatic cannulation was developed. The cannulation success rate was 55%. In addition, no pulmonary lymph contamination was found at the cannulation site.

CONCLUSION

We conclude that porcine myocardial lymphatics can be successfully cannulated for the investigation of myocardial lymphatic function.

[Bone mineral density and exercises: a cross-sectional study on Chinese athletes]

OBJECTIVES

To evaluate the effect of exercise to osteoporosis by bone mineral density (BMD) measurement of athelets comparing normal individuals in general population.

METHODS

BMD of radium, lumber spine, and femoral neck were measured by single photon absorptiometry (SPA), quantitative CT (QCT), and dual X-ray absorptiometry (DXA) respectively in athletes (n = 162, male 79, female 83) and age matched non-athletes normal population (n = 204, male 91, female 113) in Beijing.

RESULTS

BMD of all sites in all age groups of both male and female athletes are significantly higher comparing with that in non-athletic population. This predominance in athletes is even more distinctive in peak bone mass. Peak bone mass of male athletes is significantly higher than that of female athletes. Bone loss with age is less apparent in athletes than in control. However, there is an accelerated decline of BMD in lumber spine and femoral neck in 30-39 year age group in both male and female athletes, which may be due to the wanting of physical exercise.

CONCLUSIONS

Long term regular proper exercise started in adolescence may play a very important role in the prevention of osteoporosis by improving peak bone mass and decreasing bone loss.