Repression of the SUMO-conjugating enzyme UBC9 is associated with lowered double minutes and reduced tumor progression

Double minutes (DMs), extrachromosomal gene fragments found within certain tumors, have been noted to carry onco- and drug resistance genes contributing to tumor pathogenesis and progression. After screening for SUMO-related molecule expression within various tumor sample and cell line databases, we found that SUMO-conjugating enzyme UBC9 has been associated with genome instability and tumor cell DM counts, which was confirmed both in vitro and in vivo. Karyotyping determined DM counts post-UBC9 knockdown or SUMOylation inhibitor 2-D08, while RT-qPCR and Western blot were used to measure DM-carried gene expression in vitro. In vivo, fluorescence in situ hybridization (FISH) identified micronucleus (MN) expulsion. Western blot and immunofluorescence staining were then used to determine DNA damage extent, and a reporter plasmid system was constructed to detect changes in homologous recombination (HR) and non-homologous end joining (NHEJ) pathways. Our research has shown that UBC9 inhibition is able to attenuate DM formation and lower DM-carried gene expression, in turn reducing tumor growth and malignant phenotype, via MN efflux of DMs and lowering NHEJ activity to increase DNA damage. These findings thus reveal a relationship between heightened UBC9 activity, increased DM counts, and tumor progression, providing a potential approach for targeted therapies, via UBC9 inhibition.

Catalytic hairpin assembly triggering amplified DNAzyme-feedback for sensitive detection of hepatitis C virus genotype 1b

Developing a simple, reliable, and sensitive hepatitis C virus (HCV) genetic sensing platform is of great significance for diagnosing diseases and selecting appropriate antiviral treatments. Herein, a tandem nucleic acid amplification strategy for sensitive detection of HCV genotype 1b (HCV-1b) was developed by stringing the catalytic hairpin assembly (CHA) and the triggered DNAzyme amplifier. The hairpin reactants were initiated by the target to produce lots of triggering double-stranded DNA sequences which can efficiently activate the subsequent blocked DNAzyme. Thereby, the continuous cleavage of substrate was realized, resulting in the fluorescence signal amplification. The DNA-based isothermal CHA-DNAzyme (CDz) sensing platform was successfully applied for sensitive detection of HCV-1b with the limit of detection (84 pM) and showed good selectivity. Moreover, the practical detection of target DNA in the complex biologic matrix indicated that the developing strategy had good potential for early HCV infection diagnosis.

Combination of metagenomic next-generation sequencing and conventional tests unraveled pathogen profiles in infected patients undergoing allogeneic hematopoietic stem cell transplantation in Jilin Province of China

Background

Infection is the main cause of death for patients after allogeneic hematopoietic stem cell transplantation (HSCT). However, pathogen profiles still have not been reported in detail due to their heterogeneity caused by geographic region.

Objective

To evaluate the performance of metagenomic next-generation sequencing (mNGS) and summarize regional pathogen profiles of infected patients after HSCT.

Methods

From February 2021 to August 2022, 64 patients, admitted to the Department of Hematology of The First Hospital of Jilin University for HSCT and diagnosed as suspected infections, were retrospectively enrolled.

Results

A total of 38 patients were diagnosed as having infections, including bloodstream (n =17), pulmonary (n =16), central nervous system (CNS) (n =4), and chest (n =1) infections. Human betaherpesvirus 5 (CMV) was the most common pathogen in both bloodstream (n =10) and pulmonary (n =8) infections, while CNS (n =2) and chest (n =1) infections were mainly caused by Human gammaherpesvirus 4 (EBV). For bloodstream infection, Mycobacterium tuberculosis complex (n =3), Staphylococcus epidermidis (n =1), and Candida tropicalis (n =1) were also diagnosed as causative pathogens. Furthermore, mNGS combined with conventional tests can identify more causative pathogens with high sensitivity of 82.9% (95% CI 70.4-95.3%), and the total coincidence rate can reach up to 76.7% (95% CI 64.1-89.4%).

Conclusions

Our findings emphasized the importance of mNGS in diagnosing, managing, and ruling out infections, and an era of more rapid, independent, and impartial diagnosis of infections after HSCT can be expected.

[Genetic analysis of a Chinese pedigree with an allele dropout at the HLA-B locus]

OBJECTIVE

To delineate a deletional mutation of the HLA-B gene in a Chinese pedigree.

METHODS

A female patient with acute myeloid leukemia who had visited Liuzhou People's Hospital in April 2022 was selected as the study subject. Routine human leukocyte antigen (HLA) was determined by using PCR-sequence specific oligonucleotide polymorphism (PCR-SSOP) and PCR-sequence-based typing (PCR-SBT) methods. Next generation sequencing (NGS) was used to validate the candidate variant in the HLA-B gene.

RESULTS

The PCR-SBT and SSOP results for the HLA-B locus were inconsistent for the patient and her daughter. The SSOP results of the two individuals were HLA-B*35:01, 40:02 and HLA-B*35:01, 40:01, respectively. However, the PCR-SBT results has indicated a mismatch with the nearest HLA-B*35:01 at exon 4. NGS results showed that the HLA-B*35:01 had a 9 bp deletion in the intron 5. The patient's husband was HLA-B*40:01, 58:01, which was normal.

CONCLUSION

The variant in intron 5 of the HLA-B gene in this pedigree has mapped to a primer-binding region for the SBT reagent, which has affected the accuracy of PCR-SBT results.

Invasion of glioma cells through confined space requires membrane tension regulation and mechano-electrical coupling via Plexin-B2

Glioblastoma (GBM) is a malignant brain tumor with uncontrolled invasive growth. Here, we demonstrate how GBM cells usurp guidance receptor Plexin-B2 to gain biomechanical plasticity for polarized migration through confined space. Using live-cell imaging to track GBM cells negotiating microchannels, we reveal active endocytosis at cell front and filamentous actin assembly at rear to propel GBM cells through constrictions. These two processes are interconnected and governed by Plexin-B2 that orchestrates cortical actin and membrane tension, shown by biomechanical assays. Molecular dynamics simulations predict that balanced membrane and actin tension are required for optimal migratory velocity and consistency. Furthermore, Plexin-B2 mechanosensitive function requires a bendable extracellular ring structure and affects membrane internalization, permeability, phospholipid composition, as well as inner membrane surface charge. Together, our studies unveil a key element of membrane tension and mechanoelectrical coupling via Plexin-B2 that enables GBM cells to adapt to physical constraints and achieve polarized confined migration.

Aryl hydrocarbon receptor restricts axon regeneration of DRG neurons in response to injury

Injured neurons sense environmental cues to balance neural protection and axon regeneration, but the mechanisms are unclear. Here, we unveil aryl hydrocarbon receptor (AhR), a ligand-activated bHLH-PAS transcription factor, as molecular sensor and key regulator of acute stress response at the expense of axon regeneration. We demonstrate responsiveness of DRG sensory neurons to ligand-mediated AhR signaling, which functions to inhibit axon regeneration. Ahr deletion mimics the conditioning lesion in priming DRG to initiate axonogenesis gene programs; upon peripheral axotomy, Ahr ablation suppresses inflammation and stress signaling while augmenting pro-growth pathways. Moreover, comparative transcriptomics revealed signaling interactions between AhR and HIF-1α, two structurally related bHLH-PAS α units that share the dimerization partner Arnt/HIF-1β. Functional assays showed that the growth advantage of AhR-deficient DRG neurons requires HIF-1α; but in the absence of Arnt, DRG neurons can still mount a regenerative response. We further unveil a link between bHLH-PAS transcription factors and DNA hydroxymethylation in response to peripheral axotomy, while neuronal single cell RNA-seq analysis revealed a link of the AhR regulon to RNA polymerase III regulation and integrated stress response (ISR). Altogether, AhR activation favors stress coping and inflammation at the expense of axon regeneration; targeting AhR can enhance nerve repair.

Characterization of a novel variant allele, HLA-B*56:04:05, identified in a Chinese Han individual

The novel HLA-B *56:04:05 allele differs from its most closely related allele B*56:04:01:01 in exon 4.

Circadian clock regulator Bmal1 gates axon regeneration via Tet3 epigenetics in mouse sensory neurons

Axon regeneration of dorsal root ganglia (DRG) neurons after peripheral axotomy involves reconfiguration of gene regulatory circuits to establish regenerative gene programs. However, the underlying mechanisms remain unclear. Here, through an unbiased survey, we show that the binding motif of Bmal1, a central transcription factor of the circadian clock, is enriched in differentially hydroxymethylated regions (DhMRs) of mouse DRG after peripheral lesion. By applying conditional deletion of Bmal1 in neurons, in vitro and in vivo neurite outgrowth assays, as well as transcriptomic profiling, we demonstrate that Bmal1 inhibits axon regeneration, in part through a functional link with the epigenetic factor Tet3. Mechanistically, we reveal that Bmal1 acts as a gatekeeper of neuroepigenetic responses to axonal injury by limiting Tet3 expression and restricting 5hmC modifications. Bmal1-regulated genes not only concern axon growth, but also stress responses and energy homeostasis. Furthermore, we uncover an epigenetic rhythm of diurnal oscillation of Tet3 and 5hmC levels in DRG neurons, corresponding to time-of-day effect on axon growth potential. Collectively, our studies demonstrate that targeting Bmal1 enhances axon regeneration.

Hypoxic niches attract and sequester tumor-associated macrophages and cytotoxic T cells and reprogram them for immunosuppression

Glioblastoma (GBM), a highly lethal brain cancer, is notorious for immunosuppression, but the mechanisms remain unclear. Here, we documented a temporospatial patterning of tumor-associated myeloid cells (TAMs) corresponding to vascular changes during GBM progression. As tumor vessels transitioned from the initial dense regular network to later scant and engorged vasculature, TAMs shifted away from perivascular regions and trafficked to vascular-poor areas. This process was heavily influenced by the immunocompetence state of the host. Utilizing a sensitive fluorescent UnaG reporter to track tumor hypoxia, coupled with single-cell transcriptomics, we revealed that hypoxic niches attracted and sequestered TAMs and cytotoxic T lymphocytes (CTLs), where they were reprogrammed toward an immunosuppressive state. Mechanistically, we identified chemokine CCL8 and cytokine IL-1β as two hypoxic-niche factors critical for TAM trafficking and co-evolution of hypoxic zones into pseudopalisading patterns. Therefore, perturbation of TAM patterning in hypoxic zones may improve tumor control.

Plasmonic Cu2-xSe Mediated Colorimetric/Photothermal Dual-Readout Detection of Glutathione

Plasmonic nanomaterials have attracted great attention in the field of catalysis and sensing for their outstanding electrical and optical properties. Here, a representative type of nonstoichiometric Cu_2-xSe nanoparticles with typical near-infrared (NIR) localized surface plasma resonance (LSPR) properties originating from their copper deficiency was applied to catalyze the oxidation of colorless TMB into their blue product in the presence of H₂O₂, indicating they had good peroxidase-like activity. However, glutathione (GSH) inhibited the catalytic oxidation of TMB, as it can consume the reactive oxygen species. Meanwhile, it can induce the reduction of Cu(II) in Cu_2-xSe, resulting in a decrease in the degree of copper deficiency, which can lead to a reduction in the LSPR. Therefore, the catalytic ability and photothermal responses of Cu_2-xSe were decreased. Thus, in our work, a colorimetric/photothermal dual-readout array was developed for the detection of GSH. The linear calibration for GSH concentration was in the range of 1-50 μM with the LOD as 0.13 μM and 50-800 μM with the LOD as 39.27 μM. To evaluate the practicability of the assay, tomatoes and cucumbers were selected as real samples, and good recoveries indicated that the developed assay had great potential in real applications.

Global distribution and ecological risk assessment of synthetic musks in the environment

Synthetic musks, as an alternative product of natural musks, are widely used in almost all fragrances of consumer products, such as perfumes, cosmetics and detergents. During the past few decades, the production of synthetic musks has been increasing year by year, subsequently followed by large concern about their adverse effects on ecosystems and human beings. Until now, several studies have reviewed the latest development of analytical methods of synthetic musks in biological samples and cosmetics products, while there is still lack of a systematic analysis of their global distribution in different environmental media. Thus, this review summarizes the occurrence of synthetic musks in the environment including biota around the world and explores their global distribution patterns. The results show that galaxolide (HHCB), tonalide (AHTN), musk xylene (MX) and musk ketone (MK) are generally the most frequently detected synthetic musks in different samples with HHCB and AHTN being predominant. Higher concentrations of HHCB and AHTN are normally found in western countries compared to Asian countries, indicating more consumptions of these musks in western countries. The persistence, bioaccumulation and toxicity (PBT) of synthetic musks (mainly for polycyclic musks and nitro musks) are also discussed. The risk quotients (RQs) of HHCB, AHTN, MX and MK in most waters and sediments are below 0.1, reflecting a low risk to aqueous and sediment-dwelling species. In some sites, e.g., close to STPs, high risks (RQs>1) are characterized. Currently, limited data are available for macrocyclic musks and alicyclic musks in terms of either occurrence or PBT properties. More studies with an expanded scope of chemical type, geographical distribution and (synergic) toxicological effects especially from a long-term point of view are needed.

Plasmonic scattering imaging of single Cu2-xSe nanoparticle for Hg2+ detection

The development of new efficient contrast nanoprobe has been greatly concerned in the field of scattering imaging for sensitive and accurate detection of trace analytes. In this work, the non-stoichiometric Cu_2-xSe nanoparticle with typical localized surface plasmon resonance (LSPR) properties originating from their copper deficiency as a plasmonic scattering imaging probe was developed for sensitive and selective detection of Hg²⁺ under dark-field microscopy. Hg²⁺ can compete with Cu(I)/Cu(II) which were sources of optically active holes coexisting in these Cu_2-xSe nanoparticles for its higher affinity with Se^2-. The plasmonic properties of Cu_2-xSe were adjusted effectively. Thus, the color scattering images of Cu_2-xSe nanoparticles was changed from blue to cyan, and the scattering intensity was obviously enhanced with the dark-field microscopy. There was a linear relationship between the scattering intensity enhancement and the Hg²⁺ concentration in the range of 10-300 nM with a low detection limit of 1.07 nM. The proposed method has good potential for Hg²⁺ detection in the actual water samples. This work provides a new perspective on applying new plasmonic imaging probe for the reliable determination of trace heavy metal substances in the environment at a single particle level.

[Effects of long working hours exposure on occupational stress and depression symptoms in couriers in Zhejiang Province]

Objective: To understand the current situation of long working hours exposure of couriers in Zhejiang Province, and to analyze the influence of long working hours exposure levels on their occupational stress and depression symptoms, and provide a basis for promoting the physical and mental health of couriers. Methods: From September to December 2021 , 1159 couriers from Zhejiang Express Transport Companies were selected as respondents by cluster sampling, and their basic information were collected. The occupational stress and depression symptoms of the couriers were assessed using the Core Occupational Stress Scale (COSS) and the Patient Health Questionnaire-9 (PHQ-9). The effects of long work hours (>48 h per week) on the occupational stress and depression symptoms of the couriers were analyzed. Results: The average age of 1159 courier in Zhejiang Province was (33.24±8.42) years, the average weekly working hours were (63.21±18.77) h, and 75.15% (871/1159) were long-term workers. The detection rates of occupational stress and depression symptoms in courier were 32.44% (376/1159) and 32.53% (377/1159), respectively. There were significant differences in the detection rates of occupational stress and depression symptoms among couriers with different ages, educational background, marital status, monthly average income, length of service, position or post, shift status, drinking status, and average weekly working hours (P <0.05). The adjusted logistic regression analysis showed that, after adjusting for the influence of confounding factors such as age, educational background, marital status, monthly average income, length of service, position or post, shift status and drinking status, compared with the weekly working hours ≤48 h, weekly working hours of 63-77 h, 78-92 h, ≥93 h were the risk factors for occupational stress (OR=1.547, 95%CI: 1.019-2.350; OR=1.886, 95%CI: 1.184-3.006; OR=2.338, 95%CI: 1.188-4.062) and depression symptoms (OR=1.897, 95%CI: 1.258-2.860; OR=2.041, 95%CI: 1.290-3.230; OR=4.978, 95%CI: 2.551-9.715) of couriers (P<0.05) . Conclusion: Long working hours could increase the risk of occupational stress and depression symptoms among couriers. It is necessary to arrange working hours reasonably to reduce the occurrence of occupational stress and depression symptoms of couriers.

Alveolar Macrophages-Mediated Translocation of Intratracheally Delivered Perfluorocarbon Nanoparticles to Achieve Lung Cancer 19F-MR Imaging

Recent advances in intratracheal delivery strategies have sparked considerable biomedical interest in developing this promising approach for lung cancer diagnosis and treatment. However, there are very few relevant studies on the behavior and mechanism of imaging nanoparticles (NPs) after intratracheal delivery. Here, we found that nanosized perfluoro-15-crown-5-ether (PFCE NPs, ∼200 nm) exhibite significant ¹⁹F-MRI signal-to-noise ratio (SNR) enhancement than perfluorooctyl bromide (PFOB NPs) up to day 7 after intratracheal delivery. Alveolar macrophages (AMs) engulf PFCE NPs, become PFCE NPs-laden AMs, and then migrate into the tumor margin, resulting in increased tumor PFCE concentration and ¹⁹F-MRI signals. AMs-mediated translocation of PFCE NPs to lung draning lymph nodes (dLNs) decreases the background PFCE concentration. Our results shed light on the dynamic AMs-mediated translocation of intratracheally delivered PFC NPs for effective lung tumor visualization and reveal a pathway to develop and promote the clinical translation of an intratracheal delivery-based imaging strategy.

Abstract 1260: Tumor hypoxia conditions glioblastoma cells for immunosuppression

Glioblastoma (GBM) is the most common and lethal malignant brain tumor that invariably recurs after standard therapy, with a median survival of only ~16 months. A major determinant of high GBM lethality is the overall immunosuppressive tumor microenvironment and the presence of treatment resistant hypoxic niches. In a recent study, we engineered murine GBM cell line GL261 with a lentiviral HRE driven fluorescent reporter, HRE-UnaG-PEST to study the relationship between tumor hypoxia and immunosuppression. By 3-4 weeks post-transplant in mice, we observed an abundance of UnaG+ GBM cells that were organized as pseudopalisading patterns around necrotic cores, similar to histological features observed in GBM patient specimens. We also observed an accumulation of TAMs and cytotoxic T cells inside hypoxic cores surrounded by UnaG+ GBM cells, which coincided with a gradual increase in vascular disarray and development of hypoxic niches. Single cell RNA sequencing (scRNA-seq) revealed that UnaG+ GBM cells were negatively enriched for neuroinflammation, Type II IFN signaling, TNFα and NF-κB signaling pathways, and IFNα and IFNγ responses. Furthermore, the gene ontology term “Negative Regulation of Immune System Process” (including genes such as Mif, Lgals3, Sdc4, Cd44, Dusp1) was predominantly upregulated in UnaG+ GBM cells. Hypoxia transcriptional program in GL261 GBM thus favors immunosuppression. To longitudinally study the immunosuppressive transcriptional programs of hypoxic GBM cells, we combined lentiviral HRE-CreERT2 with a knock-in of CAG-loxP-STOP-loxP-tdTomato (LSL-tdTom) reporter into the Rosa26 locus as a lineage tracing reporter for hypoxia-exposed GBM cells. A subclone of GL261-HRE-CreERT2; LSL-tdTom cells that displayed low baseline expression and faithful induction of tdTomato upon exposure to 1% O2 and 4-hydroxytamoxifen was identified and intracranially transplanted in mice. After a single tamoxifen injection day 21 post-transplant, mice were traced for 2 days or 7 days before analysis. At both timepoints, we observed abundant tdTom+ GBM cells spread throughout the tumor. Few tdTom+ GBM cells showed GLUT1 expression, more so in 7-day tracing than 2-day tracing. Hence, as the tumor progressed, most tdTom+ GL261 cells no longer experienced hypoxia, likely due to new angiogenesis or migration away from hypoxic areas. No tdTom+ GL261 cells were observed in parallel control experiments where tamoxifen was not injected. To investigate if hypoxia-induced immunosuppressive adaptations are preserved along tumor progression, further scRNA-seq and FACS studies will be performed to characterize the transcriptional profile of tdTom+ GBM cells. To test if hypoxic exposure is a critical conditioning event that promotes an immunosuppressive environment in GBM, we plan to genetically eliminate hypoxic GBM cells by inducing expression of Diptheria Toxin and evaluate effect on functional state of immune cells.

Citation Format: Anirudh Sattiraju, Sangjo Kang, Hongyan Zou, Roland Friedel. Tumor hypoxia conditions glioblastoma cells for immunosuppression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1260.

Mechanism and Origins of Diastereo- and Regioselectivities of Palladium-Catalyzed Remote Diborylative Cyclization of Dienes via Chain-Walking Strategy

Density functional theory calculations have been performed to investigate the palladium-catalyzed remote diborylative cyclization of dienes. The computations reveal that the reaction proceeds through a rarely explored Pd(II)/Pd(IV) catalytic cycle, and the formal σ-bond metathesis between the alkylpalladium intermediate and B₂ pin₂ occurs via the pathway of the B-B oxidative addition/C-B reductive elimination involving the high-valent Pd(IV) species. The diastereoselectivity is determined by the migratory insertion into the Pd-C bond, which is mainly due to the combination of the torsional strain effect, steric repulsion and C-H-O hydrogen-bonding interaction. The steric hindrance around the reacting carbon group in the C-B reductive elimination turns out to be a key factor to provide the driving force of the chain walking of the Pd center to the terminal primary carbon position, enabling the experimentally observed remote regioselectivity.

Genotypic Effects of the TOMM40'523 Variant and APOE on Longitudinal Cognitive Change over 4 Years: The TOMMORROW Study

BACKGROUND

The 523 poly-T length polymorphism (rs10524523) in TOMM40 has been reported to influence longitudinal cognitive test performance within APOE ε3/3 carriers. The results from prior studies are inconsistent. It is also unclear whether specific APOE and TOMM40 genotypes contribute to heterogeneity in longitudinal cognitive performance during the preclinical stages of AD.

OBJECTIVES

To determine the effects of these genes on longitudinal cognitive change in early preclinical stages of AD, we used the clinical trial data from the recently concluded TOMMORROW study to examine the effects of APOE and TOMM40 genotypes on neuropsychological test performance.

DESIGN

A phase 3, double-blind, placebo-controlled, randomized clinical trial.

SETTING

Academic affiliated and private research clinics in Australia, Germany, Switzerland, the UK, and the USA.

PARTICIPANTS

Cognitively normal older adults aged 65 to 83.

INTERVENTION

Pioglitazone tablet.

MEASUREMENTS

Participants from the TOMMORROW trial were stratified based on APOE genotype (APOE ε3/3, APOE ε3/4, APOE ε4/4). APOE ε3/3 carriers were further stratified by TOMM40'523 genotype. The final analysis dataset consists of 1,330 APOE ε3/3 carriers and 7,001 visits. Linear mixed models were used to compare the rates of decline in cognition across APOE groups and the APOE ε3/3 carriers with different TOMM40'523 genotypes.

RESULTS

APOE ε3/4 and APOE ε4/4 genotypes compared with the APOE ε3/3 genotype were associated with worse performance on measures of global cognition, episodic memory, and expressive language. Further, over the four years of observation, the APOE ε3/3 carriers with the TOMM40'523-S/S genotype showed better global cognition and accelerated rates of cognitive decline on tests of global cognition, executive function, and attentional processing compared to APOE ε3/3 carriers with TOMM40'523-S/VL and VL/VL genotypes and compared to the APOE ε3/4 and APOE ε4/4 carriers.

CONCLUSIONS

We suggest that both APOE and TOMM40 genotypes may independently contribute to cognitive heterogeneity in the pre-MCI stages of AD. Controlling for this genetic variability will be important in clinical trials designed to slow the rate of cognitive decline and/or prevent symptom onset in preclinical AD.

c-Met-Targeting 19F MRI Nanoparticles with Ultralong Tumor Retention for Precisely Detecting Small or Ill-Defined Colorectal Liver Metastases

Purpose

Precisely detecting colorectal liver metastases (CLMs), the leading cause of colorectal cancer-associated mortality, is extremely important. ¹H MRI with high soft tissue resolution plays a key role in the diagnosing liver lesions; however, precise detecting CLMs by ¹H MRI is a great challenge due to the limited sensitivity. Even though contrast agents may improve the sensitivity, due to their short half-life, repeated injections are required to monitor the changes of CLMs. Herein, we synthesized c-Met-targeting peptide-functionalized perfluoro-15-crown-5-ether nanoparticles (AH111972-PFCE NPs), for highly sensitive and early diagnosis of small CLMs.

Methods

The size, morphology and optimal properties of the AH111972-PFCE NPs were characterized. c-Met specificity of the AH111972-PFCE NPs was validated by in vitro experiment and in vivo ¹⁹F MRI study in the subcutaneous tumor murine model. The molecular imaging practicability and long tumor retention of the AH111972-PFCE NPs were evaluated in the liver metastases mouse model. The biocompatibility of the AH111972-PFCE NPs was assessed by toxicity study.

Results

AH111972-PFCE NPs with regular shape have particle size of 89.3 ± 17.8 nm. The AH111972-PFCE NPs exhibit high specificity, strong c-Met-targeting ability, and precise detection capability of CLMs, especially small or ill-defined fused metastases in ¹H MRI. Moreover, AH111972-PFCE NPs could be ultralong retained in metastatic liver tumors for at least 7 days, which is conductive to the implementation of continuous therapeutic efficacy monitoring. The NPs with minimal side effects and good biocompatibility are cleared mainly via the spleen and liver.

Conclusion

The c-Met targeting and ultralong tumor retention of AH111972-PFCE NPs will contribute to increasing therapeutic agent accumulation in metastatic sites, laying a foundation for CLMs diagnosis and further c-Met targeted treatment integration. This work provides a promising nanoplatform for the future clinical application to patients with CLMs.

Apple-Net: A Model Based on Improved YOLOv5 to Detect the Apple Leaf Diseases

Effective identification of apple leaf diseases can reduce pesticide spraying and improve apple fruit yield, which is significant to agriculture. However, the existing apple leaf disease detection models lack consideration of disease diversity and accuracy, which hinders the application of intelligent agriculture in the apple industry. In this paper, we explore an accurate and robust detection model for apple leaf disease called Apple-Net, improving the conventional YOLOv5 network by adding the Feature Enhancement Module (FEM) and Coordinate Attention (CA) methods. The combination of the feature pyramid and pan in YOLOv5 can obtain richer semantic information and enhance the semantic information of low-level feature maps but lacks the output of multi-scale information. Thus, the FEM was adopted to improve the output of multi-scale information, and the CA was used to improve the detection efficiency. The experimental results show that Apple-Net achieves a higher mAP@0.5 (95.9%) and precision (93.1%) than four classic target detection models, thus proving that Apple-Net achieves more competitive results on apple leaf disease identification.

An Osimertinib-Perfluorocarbon Nanoemulsion with Excellent Targeted Therapeutic Efficacy in Non-small Cell Lung Cancer: Achieving Intratracheal and Intravenous Administration

Low accumulation of anticancer drugs in tumors and serious systemic toxicity remain the main challenges to the clinical efficiency of pharmaceuticals. Pulmonary delivery of nanoscale-based drug delivery systems offered a strategy to increase antitumor activity with minimal adverse exposure. Herein, we report an osimertinib-loaded perfluoro-15-crown-5-ether (AZD9291-PFCE) nanoemulsion, through intratracheal and intravenous delivery, synergizes with ¹⁹F magnetic resonance imaging (¹⁹F MRI)-guided low-intensity focused ultrasound (LIFU) for lung cancer therapy. Pulmonary delivery of AZD9291-PFCE nanoemulsion in orthotopic lung carcinoma models achieves quick distribution of the nanoemulsion in lung tissues and tumors without short-term and long-term toxic effects. Furthermore, LIFU can trigger drug release from the AZD9291-PFCE nanoemulsion and specifically increases tumor vascular and tumor tissue permeability. ¹⁹F MRI was applied to quantify nanoemulsion accumulation in tumors in real time after LIFU irradiation. We validate the treatment effect of AZD9291-PFCE nanoemulsion in resected human lung cancer tissues, proving the translational potential to enhance clinical outcomes of lung cancer therapy. Thus, this work presents a promising pulmonary nanoemulsion delivery system of osimertinib (AZD9291) for targeted therapy of lung cancer without severe side effects.

Fluorescence turn-on Cu2-xSe@HA-rhodamine 6G FRET nanoprobe for hyaluronidase detection and imaging

The application of nanostructures to design fluorescence resonance energy transfer (FRET) based sensing platforms has been greatly concerned with the demand for sensitive and selective detection of biomolecules. Here, a novel sensitive turn-on fluorescence strategy based on the FRET mechanism has been designed for hyaluronidase (HAase) detection through the modulation of Cu_2-xSe@HA-Rh6G nanoprobe fabricated by self-assembly of rhodamine 6G (Rh6G) together with Cu_2-xSe@HA nanoparticles through electrostatic adsorption. The Cu_2-xSe@HA had extensive localized surface plasma resonance (LSPR) absorption in the wide range of ultraviolet (UV) to near-infrared (NIR) wavelengths and showed good light capture characteristics, which can be acted as good acceptors in the FRET interactions with Rh6G, inducing its efficient fluorescence quenching. In the presence of HAase, the FRET process was disrupted and the fluorescence signal was recovered. In the range of 0.1-10.0 U/mL, the fluorescence recovery of Rh6G showed a good linear relationship with the concentration of HAase, and the detection limit was 0.06 U/mL. The sensing platform has been used for HAase detection in real urine samples and cancer cells imaging.

Pulmonary Delivery of Theranostic Nanoclusters for Lung Cancer Ferroptosis with Enhanced Chemodynamic/Radiation Synergistic Therapy

Inefficient tumor accumulation and penetration remain as the main challenges to therapy efficacy of lung cancer. Local delivery of smart nanoclusters can increase drug penetration and provide superior antitumor effects than systemic routes. Here, we report self-assembled pH-sensitive superparamagnetic iron oxide nanoclusters (SPIONCs) that enhance in situ ferroptosis and apoptosis with radiotherapy and chemodynamic therapy. After pulmonary delivery in orthotopic lung cancer, SPIONCs disintegrate into smaller nanoparticles and release more iron ions in an acidic microenvironment. Under single-dose X-ray irradiation, endogenous superoxide dismutase converts superoxide radicals produced by mitochondria to hydrogen peroxide, which in turn generates hydroxyl radicals by the Fenton reaction from iron ions accumulated inside the tumor. Finally, irradiation and iron ions enhance tumor lipid peroxidation and induce cell apoptosis and ferroptosis. Thus, rationally designed pulmonary delivered nanoclusters provide a promising strategy for noninvasive imaging of lung cancer and synergistic therapy.

Critical Current Density and Meissner Effect of Smart Meta-Superconductor MgB2 and Bi(Pb)SrCaCuO

The smart meta-superconductor MgB₂ and Bi(Pb)SrCaCuO increase the superconducting transition temperature (T_C), but the changes in the transport critical current density (J_C) and Meissner effect are still unknown. Here, we investigated the J_C and Meissner effect of smart meta-superconductor MgB₂ and Bi(Pb)SrCaCuO. The use of the standard four-probe method shows that Y₂O₃:Eu³⁺ and Y₂O₃:Eu³⁺+Ag inhomogeneous phase significantly increase the J_C, and J_C decreases to a minimum value at a higher temperature. The Meissner effect was measured by direct current magnetization. The doping of Y₂O₃:Eu³⁺ and Y₂O₃:Eu³⁺+Ag luminescent inhomogeneous phase causes a Meissner effect of MgB₂ and Bi(Pb)SrCaCuO at a higher temperature, while the non-luminescent dopant reduces the temperature at which samples have Meissner effect. The introduction of luminescent inhomogeneous phase in conventional MgB₂ and copper oxide high-temperature Bi(Pb)SrCaCuO superconductor increases the T_C and J_C, and Meissner effect is exerted at higher temperature. Therefore, smart meta-superconductivity is suitable for conventional and copper oxide high-temperature superconductors.

Macrophages facilitate peripheral nerve regeneration by organizing regeneration tracks through Plexin-B2

In this study, Li et al. investigated the mechanisms underlying the regeneration of peripheral nerves, which is guided by regeneration tracks formed through an interplay of many cell types. They demonstrate that macrophages are mobilized ahead of Schwann cells in the nerve bridge after transection injury to participate in building regeneration tracks. This requires the function of guidance receptor Plexin-B2, which is robustly up-regulated in infiltrating macrophages in injured nerve.

The regeneration of peripheral nerves is guided by regeneration tracks formed through an interplay of many cell types, but the underlying signaling pathways remain unclear. Here, we demonstrate that macrophages are mobilized ahead of Schwann cells in the nerve bridge after transection injury to participate in building regeneration tracks. This requires the function of guidance receptor Plexin-B2, which is robustly up-regulated in infiltrating macrophages in injured nerves. Conditional deletion of Plexin-B2 in myeloid lineage resulted in not only macrophage misalignment but also matrix disarray and Schwann cell disorganization, leading to misguided axons and delayed functional recovery. Plexin-B2 is not required for macrophage recruitment or activation but enables macrophages to steer clear of colliding axons, in particular the growth cones at the tip of regenerating axons, leading to parallel alignment postcollision. Together, our studies unveil a novel reparative function of macrophages and the importance of Plexin-B2-mediated collision-dependent contact avoidance between macrophages and regenerating axons in forming regeneration tracks during peripheral nerve regeneration.

Abstract P022: Reciprocal influence of immune response and tumor hypoxia during glioblastoma progression

Tumor hypoxia is linked to poor outcome for glioblastoma (GBM), a highly malignant brain cancer, but underlying mechanisms and instigators that initiate tumor hypoxia remain unclear. We tracked tumor hypoxia in GBM in mice using a sensitive fluorescent reporter. We revealed that tumor hypoxia functions as a critical link between immune cells and tumor cells that drives malignant potency and immunosuppression in GBM. Single-cell RNA sequencing analysis revealed that hypoxic GBM cells are quiescent, display a mesenchymal transition, are more represented in recurrent GBM and predict worse patient outcome. Interestingly, the in vivo GBM hypoxia gene signatures surprisingly showed an enrichment for immune pathways. We unveiled two potential mechanisms of hypoxia-induced immunosuppression: by sequestrating activated immune cells in hypoxia zones, thus limiting inflammatory spread and cutting off immune cell communication, and by reprograming entrapped immune cells towards an immunotolerant state. Reciprocally, entrapped TAMs release CCL8 and IL1β as hypoxic niche factors that not only reinforce immune cell retainment in hypoxic cores, but also shape the transcriptional response of hypoxic GBM cells. Contrary to the conventional viewpoint that hypoxia arises from rapid tumor expansion outstripping vascular supply, we discovered anticancer immunity as an important driving force of tumor hypoxia; attenuating immune responses by implanting GBM in host mice with immunodeficiency or IL1β deletion greatly decreased GBM hypoxia. Altogether, our study revealed a reciprocal influence of anticancer immunity and tumor hypoxia, which has significant ramifications for prognosis and immunotherapy for GBM.

Citation Format: Anirudh Sattiraju, Valerie Marallano, Zhihong Chen, Sangjo Kang, Concetta Brusco, Aarthi Ramakrishnan, Li Shen, Dolores Hambardzumyan, Roland H. Friedel, Hongyan Zou. Reciprocal influence of immune response and tumor hypoxia during glioblastoma progression [abstract]. In: Abstracts: AACR Virtual Special Conference: Tumor Immunology and Immunotherapy; 2021 Oct 5-6. Philadelphia (PA): AACR; Cancer Immunol Res 2022;10(1 Suppl):Abstract nr P022.

Palladium-Catalyzed Regio- and Chemoselective Double-Alkoxycarbonylation of 1,3-Diynes: A Computational Study

The palladium-catalyzed double-alkoxycarbonylation of 1,3-diynes provides an efficient approach for the selective synthesis of 1,2,3,4-tetrasubstituted conjugated dienes. In this report, density functional theory calculations have been performed to elucidate the...

Carbon dots as nanocatalytic medicine for anti-inflammation therapy

Aberrant reactive oxygen species (ROS) generation is one of the crucial mediators in the pathogenesis of inflammation. So, the development of nanocatalytic medicine to catalyze the ROS-scavenging reactions in pathological regions are promising for anti-inflammatory therapy. Herein, a type of biocompatible metal free carbon dots is prepared via a hydrothermal method which can exhibit peroxidase (POD)-like, catalase (CAT)-like and superoxide dismutase (SOD)-like activities. It has been found that the carbon dots have the capability to efficiently deplete the excessive ROS such as peroxide (H₂O₂)_, superoxide anion (O₂^-) and hydroxyl radical (OH) for their abundant functional groups. After the tail injection in mice with liver inflammation induced by lipopolysaccharide, the carbon dots efficiently reduced the excessive production of ROS and proinflammatory cytokines in vitro. Both in vitro and in vivo results endowed the biocompatible carbon dots with great potential in nanocatalytic medicine for the treatment of disease.

Self-Targeting Carbon Quantum Dots for Peroxynitrite Detection and Imaging in Live Cells

Peroxynitrite (ONOO^-), a highly reactive nitrogen species (RNS) generated mainly in mitochondria, has been identified to be associated with numerous pathophysiological processes, and thus accurate ONOO^- imaging with superior sensitivity and selectivity is highly desirable. Herein, we prepared a new type of carbon quantum dots (CQDs) with mitochondria-targeting function without the aid of any targeting molecules via a simple one-step hydrothermal route. The as-prepared CQDs not only displayed relatively uniform size distribution, few surface defects, high photostability, and excellent biocompatibility but also exhibited good selective fluorescence turn-off response toward ONOO^-, owing to the oxidation of amino groups on the surface of carbon dots. A great linear correlation between the quenching efficiency and ONOO^- concentration in the range from 0.15 to 1.0 μM with a detection limit of 38.9 nM is shown. Moreover, the as-prepared CQDs acting as a functional optical probe through a self-targeting mechanism were successfully applied for in situ visualization of endogenous ONOO^- generated in the mitochondria of live cells, providing great promise for elucidating the complex biological roles of ONOO^- in related pathological processes.

TAMI-59. RECIPROCAL IMPACT OF CANCER IMMUNITY AND TUMOR HYPOXIA DURING GLIOBLASTOMA PROGRESSION

Tumor hypoxia is linked to poor outcome for glioblastoma (GBM), a highly malignant brain cancer, but the underlying mechanisms and the environmental factors that initiate tumor hypoxia are poorly understood. We tracked tumor hypoxia in GBM in immunocompetent mice with a hypoxia sensitive fluorescent reporter combined with single cell transcriptomics. We found that hypoxic GBM cells are quiescent, immunosuppressive and display a mesenchymal transition, all of which are linked to malignant potency. We also captured in vivo hypoxia gene signature, which is more represented in recurrent GBM and predicts worse outcome. Interestingly, hypoxic GBM cells is a diverse population, consisted of four subclusters, and enriched for immune pathways. Concordantly, our reporter highlighted a distinct geographic pattern of immune cells in hypoxic regions, with phagocytic tumor-associated macrophages (TAMs) and CD8+ cytotoxic T cells (CTLs) congregated in hypoxic cores confined by hypoxic GBM cells in pseudo-palisading patterns. Mechanistically, this is a dynamic temporospatial process, requiring cytokine CCL8. Remarkably, the sequestered TAMs also experience hypoxia, and they are reprogrammed to express immunotolerant markers by factors released from hypoxic GBM cells. Contrary to the conventional viewpoint that hypoxia arises from rapid tumor expansion outstripping vascular supply, we discovered anticancer immunity as an important driving force of tumor hypoxia; attenuating immune responses by implanting GBM in host mice with immunodeficiency or IL1β deletion greatly decreased GBM hypoxia. Analyses of human patient GBM samples highlighted a connection of mesenchymal subtype, immune response, and tumor hypoxia, all contributing to poor survival. Altogether, our study revealed a reciprocal influence of anti-tumor immunity and tumor hypoxia, which has significant ramifications for prognosis and immunotherapy for GBM.

TAMI-60. MODULATION OF CELL BIOMECHANICS THROUGH GUIDANCE RECEPTOR PLEXIN-B2 FACILITATES GLIOBLASTOMA INFILTRATION

Infiltrative growth is a major cause of the high lethality of malignant brain tumors such as glioblastoma (GBM). The study of the contribution of biomechanical processes to GBM invasion is an emerging field. We show here that GBM cells upregulate the guidance receptor Plexin-B2 to gain invasiveness by modulating their biomechanical properties. Deletion of Plexin-B2 in GBM stem cells limited tumor spread and shifted invasion paths from axon fiber tracts to perivascular routes. On a cellular level, Plexin-B2 adjusts cell adhesiveness, migratory responses to different matrix stiffness, and actomyosin dynamics, thus empowering GBM cells to leave stiff tumor bulk and infiltrate softer brain parenchyma. Correspondingly, gene signatures affected by Plexin-B2 were associated with locomotor regulation, matrix interactions, and cellular biomechanics. On a molecular level, the intracellular Ras-GAP domain contributed to Plexin-B2 function, while the signaling relationship with downstream effectors Rap1/2 appeared variable between GBM stem cell lines, reflecting intertumoral heterogeneity. Our studies have established Plexin-B2 as a modulator of cell biomechanics that is usurped by GBM cells to gain invasiveness. Ongoing investigations focus on the regulation of the biomechanical properties of cell membrane and cell actomyosin cortex through plexins that provide GBM cells with the mechanical dynamics to penetrate to restricted space.

TAMI-61. EXAMINING THE ROLE OF HYPOXIA INDUCED GENES CXCR4 AND NXPH4 IN INVASION OF HYPOXIC GLIOBLASTOMA CELLS

Hypoxia (low oxygen) has been associated with adverse effects in tumor biology by exaggerating the capabilities of invasion, proliferation, and survival of tumor cells within the tumor microenvironment. We engineered glioblastoma (GBM) proneural cells with a novel hypoxia reporter, HRE-UnaG, to study areas of tumor hypoxia and the effects that these hypoxic cells have on tumorigenesis. Single cell RNA-seq analysis from a mouse intracranially injected with our HRE dUnaG GBM cells revealed a shift to a mesenchymal state upon hypoxia (detected by expression of UnaG). Two genes, CXCR4 and NXPH4, were identified as being specifically induced in the hypoxic population. Our studies focus on the hypothesis that these two hypoxia induced genes, CXCR4 and NXPH4, are upregulated in hypoxic GBM cells, which may allow tumor cells to become more aggressive and resistant to conventional forms of therapies. GBM cells will be transduced with lentiviral vectors for Dox inducible shRNA knockdown of CXCR4 or NXPH4 to test specific contribution of these genes to the phenotype of the hypoxic population, with particular focus on the change in invasion and overall tumor burden upon gene silencing.

TAMI-21. TUMOR-ASSOCIATED MICROGLIA GUIDE GBM INFILTRATION VIA PLEXIN-B2

Glioblastoma (GBM) is the most common malignant primary brain tumor. The nature of invasiveness of GBM makes complete surgical resection difficult. However, how GBM cells achieve wide infiltration in the brain is poorly understood. Microglia, the resident immune cells in the brain can support GBM growth and invasion, but the underlying mechanisms remain elusive. Here, we show that microglia are activated in a wide field away from tumor boundaries, ahead of tumor cell infiltration. Invading GBM cells are in close contact with microglia, progressively aligned with one another in the direction of tumor invasion. Moreover, ECM is also aligned with the infiltrating tumor and microglia, which may serve as invasion tracks in the brain. Mechanistically, we demonstrate that microglia direct cellular alignment and ECM remodeling in the invasion tracks through an axon guidance receptor Plexin-B2. Myeloid-specific ablation of Plexin-B2 perturbs microglia and tumor cell alignment, microglia migration, ECM organization, and GBM invasiveness. Together, our data reveal a hitherto under-appreciated role of microglia in providing directional cues for GBM invasion through physical interaction and alignment of ECM and tumor cells, thus providing new insights and novel molecular targets in curbing GBM invasion.

[The study of the impact by atractylenolide-1 on inflammatory cytokine, autophagy and apoptosis in alveolar macrophages of silicosis patients]

Objective: To explore the effect of atractylenolide-1 (ATL-Ⅰ) on alveolar macrophages in silicosis patients. Methods: In December 2019, 12 male silicosis patients treated in Beidaihe Sanatorium for Chinese Coal Miners from July to September 2019 were selected by random sampling. Their alveolar macrophages were collected and divided into control group, ATL-Ⅰ group (100 μmol/L) and dimethyl sulfoxide (DMSO) group (100 μmol/L) . The exprossion levels of inflammatory factor interleukin-1β (IL-1β) , interleukin-6 (IL-6) , tumor necrosis factor α (TNF-α) were detected by enzyme-linked immunosorbent assay. The expression levels of autophagy associated protein microtubule associated protein light chain 3 (LC3) , autophagy substrate protein p62, lysosome associated membrane protein 2 (LAMP2) , apoptosis associated protein Cleaved caspase-3, nuclear factor kappa B (NF-κB) and its phosphorylated form (p-NF-κB) were detected by Western blot. Results: Compared with the control group and DMSO group, the expression levels of IL-1β, IL-6, TNF-α in alveolar macrophages decreased significantly in the ATL-Ⅰ group (P<0.05) , and the expression levels of p-NF-κB, the ratio of LC3-Ⅱ/LC3-Ⅰ also decreased significantly in the ATL-Ⅰ group (P<0.05) . However, the expression levels of NF-κB, LAMP2, p62 and Cleaved caspase-3 in the ATL-Ⅰ group were not statistically different from those in the control group and DMSO group (P>0.05) . There was no statistically significant differences in the expression of the above indexes between the control group and DMSO group (P>0.05) . Conclusion: ATL-Ⅰ may reduce the release of inflammatory factors from alveolar macrophages and inhibit the activity of autophagy in silicosis patients, but it may not reduce the level of apoptosis.

Endoscopic sinus surgery improves Eustachian tube function in patients with chronic rhinosinusitis: a multicenter prospective study

BACKGROUND

Patients with chronic rhinosinusitis (CRS) often have Eustachian tube dysfunction (ETD) symptoms. This study aimed to prospectively investigate the effect of endoscopic sinus surgery (ESS) on improvement of Eustachian tube function in CRS patients with ETD from a Chinese population and determine factors associated with improvement.

METHODS

A prospective study was performed in CRS patients with ETD who underwent ESS from 3 tertiary medical centers in south China. The Eustachian tube Dysfunction Questionnaire 7 (ETDQ-7), Sinonasal Outcome Test 22 (SNOT-22), tympanograms, endoscopic findings and Valsalva maneuver were recorded and analyzed preoperatively and postoperatively at 8-12 weeks.

RESULTS

A total of 70 CRS patients with ETD were included in this study. The ETDQ-7 score and the ability of positive Valsalva maneuver in CRS patients were significantly improved postoperatively at 8-12 weeks. The number of patients with type A tympanogram was increased postoperatively. Reduced Eustachian tube mucosal inflammation was also observed postoperatively. In addition, ESS appeared to reverse slight tympanic membrane atelectasis after 8-12 weeks. Moreover, improvement in tympanogram was presented in more than half of CRS patients with concomitant otitis media with effusion postoperatively at 8-12 weeks. Univariate and multivariate analysis revealed failure of normalization of ETDQ-7 postoperatively was associated with concomitant allergic rhinitis and higher preoperative SNOT-22 score.

CONCLUSIONS

This study confirms Eustachian tube function is often improved after ESS in CRS patients with ETD. Concomitant allergic rhinitis and higher preoperative SNOT-22 score are associated with failure of normalization of ETD symptoms.

A critical review on the distribution and ecological risk assessment of steroid hormones in the environment in China

During past two decades, steroid hormones have raised significant public concerns due to their potential adverse effects on the hormonal functions of aquatic organisms and humans. Considering China being a big producer and consumer of steroid hormones, we summarize the current contamination status of steroid hormones in different environmental compartments in China, and preliminarily assess the associated risks to ecological systems. The results show that steroid hormones are ubiquitously present in Chinese surface waters where estrogens are the most studied steroids compared with androgens, progestogens and glucocorticoids. Estrone (E1), 17β-estradiol (17β-E2) and estriol (E3) are generally the dominant steroid estrogens in Chinese surface waters, whereas for the other steroids, androsterone (ADR), epi-androsterone (EADR), progesterone (PGT), cortisol (CRL) and cortisone (CRN) have relatively large contributions. Meanwhile, the investigations for the other environmental media such as particles, sediments, soils and groundwater have been limited, as well as for steroid conjugates and metabolites. The median risk quotients of most steroid hormones in surface waters and sediments are lower than 1, indicating low to moderate risks to local organisms. This review provides a full picture of steroid distribution and ecological risks in China, which may be useful for future monitoring and risk assessment. More studies may focus on the analysis of steroid conjugates, metabolites, solid phase fractions, analytical method development and acute/chronic toxicities in different matrices to pursue a more precise and holistic risk assessment.

Adaptive Admixture of HLA Class I Allotypes Enhanced Genetically Determined Strength of Natural Killer Cells in East Asians

Human natural killer (NK) cells are essential for controlling infection, cancer, and fetal development. NK cell functions are modulated by interactions between polymorphic inhibitory killer cell immunoglobulin-like receptors (KIR) and polymorphic HLA-A, -B, and -C ligands expressed on tissue cells. All HLA-C alleles encode a KIR ligand and contribute to reproduction and immunity. In contrast, only some HLA-A and -B alleles encode KIR ligands and they focus on immunity. By high-resolution analysis of KIR and HLA-A, -B, and -C genes, we show that the Chinese Southern Han (CHS) are significantly enriched for interactions between inhibitory KIR and HLA-A and -B. This enrichment has had substantial input through population admixture with neighboring populations, who contributed HLA class I haplotypes expressing the KIR ligands B*46:01 and B*58:01, which subsequently rose to high frequency by natural selection. Consequently, over 80% of Southern Han HLA haplotypes encode more than one KIR ligand. Complementing the high number of KIR ligands, the CHS KIR locus combines a high frequency of genes expressing potent inhibitory KIR, with a low frequency of those expressing activating KIR. The Southern Han centromeric KIR region encodes strong, conserved, inhibitory HLA-C-specific receptors, and the telomeric region provides a high number and diversity of inhibitory HLA-A and -B-specific receptors. In all these characteristics, the CHS represent other East Asians, whose NK cell repertoires are thus enhanced in quantity, diversity, and effector strength, likely augmenting resistance to endemic viral infections.

[Evaluation of kurtosis on hearing loss caused by non-steady state noise in general equipment manufacturing industry]

Objective: To study the effect of occupational exposure to non-steady state noise on hearing loss in the general equipment manufacturing industry, and to explore the feasibility of applying kurtosis index to evaluate hearing loss caused by non-steady state noise. Methods: A total of 233 workers exposed to non-steady state noise in 6 general equipment manufacturing enterprises were selected as the observation group, and 237 workers exposed to steady noise in 4 textile enterprises were selected as the control group between 2012 and 2018. Personal normalized continuous A-weighted sound pressure level equivalent to an 8 h-working-day (L(Aeq, 8 h)) was determined by a noise dosimeter. Cumulation noise exposure (CNE) was calculated from L(Aeq, 8 h) and related working age, and the CNE was adjusted by using noise kurtosis (CNE' after adjustment) . Meanwhile, questionnaires and hearing loss tests were performed for all subjects. The changes in the threshold of high-frequency hearing and the incidence of high-frequency hearing loss caused by noise in the two groups were compared before and after the adjustment of the kurtosis of CNE. The correlation between CNE and the incidence of high-frequency hearing loss before and after kurtosis adjustment was analyzed. Results: There was an difference between the 3000-8000 Hz hearing threshold of workers in different CNE groups (P<0.05) . logistic regression analysis showed that CNE was a risk factor of high-frequency hearing loss for workers in the observation group (OR=1.189, P<0.05) , and trend Chi-square test showed that the incidence of high-frequency hearing loss increased with CNE levels (χ(2)(trend)=34.415, P<0.05) .Before the kurtosis adjustment, in the CNE 95~<110 dB (A) ·year level group, the incidence of high-frequency hearing loss and the high-frequency hearing threshold in the observation group were significantly higher than those in the control group (P<0.05) . After kurtosis adjustment, there was no significant difference in the incidence of high-frequency hearing loss between the observation group and the control group in each level group (P>0.05) . The correlation between CNE after kurtosis adjustment and the incidence of high-frequency hearing loss was better than that before adjustment (after R(2) adjustment >before R(2) adjustment) . Conclusion: The effect of non-steady state noise on high-frequency hearing loss of workers in general equipment industry increases with the increase of CNE, and the effect of non-steady state noise on high-frequency hearing loss of workers is greater than that of steady noise. CNE' can be used to evaluate the hearing loss caused by non-steady state noise.

Psychological stress and its correlates in Chinese patients with acute coronary syndrome

Funding Acknowledgements

None.

Background

Psychological stress is associated with high incidence of coronary heart disease and increases the risk of mortality and poor health status. Although a few studies have investigated psychological stress in this population, this problem is usually unrecognized and untreated in most Chinese patients with acute coronary syndrome. There is insufficient information regarding the features of psychological stress and associated factors among this population.

Purpose

This study aimed to assess the level of psychological stress and to identify its correlates in Chinese patients with acute coronary syndrome.

Methods

Patients aged over 18 years and with acute coronary syndrome were invited to participate in a cross-sectional survey in two tertiary public hospitals in China, from June to July 2019. A total of 332 patients completed measures of sociodemographic and clinical characteristics, psychological stress (10-item Perceived Stress Scale), and illness perception (Brief Illness Perceptions Questionnaire). Independent sample t-tests, bivariate correlations, and multivariable linear regression were performed to analyze potential correlates, including age, gender, education level, employment status, income, episode of illness, revascularization procedure, comorbidities, body mass index, blood pressure, blood glucose, blood lipids, and illness perception.

Results

The average patient age was 62.2 years, 67.5% were male, and 54.2% had less than high school education. The mean score for psychological stress was 21.30 ± 3.99 and 66.9% of patients had high psychological stress (score ≥ 20). Multivariable regression analysis showed that being overweight/obesity versus normal weight (body mass index:  ≥ 24 kg/m2 versus &lt; 24 kg/m2) was associated with lower psychological stress (β =  -0.134, p = 0.007). Having a high level of fasting blood glucose (≥ 6.1 mmol/L) versus normal fasting blood glucose (&lt; 6.1 mmol/L) was associated with high psychological stress (β = 0.123, p = 0.017). Additionally, negative cognitive illness perception (β = 0.190, p = 0.01), negative emotional illness perception (β = 0.290, p &lt; 0.001), and poor illness understanding (β = 0.118, p = 0.032) were associated with high psychological stress.

Conclusions

Patients with acute coronary syndrome experience high psychological stress that is significantly correlated with body mass index, fasting blood glucose, and illness perception. Health professionals should recognize this issue and interventions looking to relive psychological stress may benefit from targeting these correlates.

POS0884 THE ENHANCED LIVER FIBROSIS (ELF) SCORE AS A BIOMARKER OF SKIN FIBROSIS IN SYSTEMIC SCLEROSIS

Background:

Serum fibrotic markers for systemic sclerosis (SSc) remain limited. The Enhanced Liver Fibrosis (ELF) score, originally derived and validated in patients with chronic liver disease, is an algorithm combining 3 serum markers, known as procollagen type III amino terminal propeptide (PIIINP), tissue inhibitor of metalloproteinases 1 (TIMP-1), and hyaluronic acid (HA). The combined score was proved to be superior to the single components in reflecting the severity of liver fibrosis. However, the performance of ELF score and its components has not been fully validated in SSc.

Objectives:

To investigate PIIINP, TIMP-1, HA, and the combined algorithm ELF score as fibrotic markers for SSc skin involvement.

Methods:

Eighty SSc patients (44 dcSSc and 36 lcSSc), fulfilling the 2013 ACR/EULAR criteria with the absence of chronic liver diseases, were enrolled. Eighty age- and sex- matched healthy controls were also included. Serum PIIINP and HA levels were quantified by chemiluminescence immunoassay. Serum TIMP-1 levels were determined by enzyme-linked immunosorbent assay. The ELF score was calculated using the formula ELF score= 2.494 + 0.846*ln(HA) + 0.735*ln(PIIINP) + 0.391*ln(TIMP-1). Results were correlated with clinical profiles including modified Rodnan skin score (mRSS) and interstitial lung disease (ILD).

Results:

Compared with healthy controls, patients with SSc showed significantly elevated serum PIIINP (11.2±4.8 vs. 5.73±1.4μg/L, p<0.001), TIMP-I (123.7±78.6 vs. 67.8±26.5 ng/ml, p<0.001), and ELF score (10.5±0.9 vs. 9.7±0.4, P<0.001). Even higher levels of PIIINP, TIMP-1, and ELF score were observed in dcSSc patients, compared with lcSSc patients (p<0.001, p=0.024, p=0.003, respectively). No significant difference was found in the levels of serum HA between patients and controls. Strong correlations were observed between mRSS and ELF score (r=0.54, p<0.001), and between mRSS and PIIINP(r=0.62, p<0.001), whereas only weak correlations could be observed between mRSS and TIMP-1 (r=0.28, p=0.02), and between mRSS and HA (r=0.26, p=0.03). When stratified by ELF score, using cutoffs proposed for liver fibrosis and cirrhosis, SSc patients with ELF<9.8 showed the lowest mRSS on average, while patients with ELF>11.3 showed the highest (p<0.001). When stratified by serum PIIINP levels, using the 25th and 75th percentiles, SSc patients with serum PIIIINP levels<7.8μg/L showed the lowest mRSS on average, while patients with PIIINP>14.0μg/L showed the highest (p<0.001). Neither the ELF score nor its components showed significant difference between patients with and without ILD.

Conclusion:

The ELF score could be used for reflecting the severity of overall skin involvement in SSc, and serum PIIINP also increased in parallel with the increase of mRSS. Longitudinal prospective studies exploring ELF score or serum PIIINP as fibrotic markers and outcome measures of SSc are warranted.

References:

[1]Lichtinghagen R, Pietsch D, Bantel H, et al. The Enhanced Liver Fibrosis (ELF) score: Normal values, influence factors and proposed cut-off values. Journal of Hepatology. 2013; 59: 236-42.

[2]Abignano G, Blagojevic J, Bissell LA, et al. European multicentre study validates enhanced liver fibrosis test as biomarker of fibrosis in systemic sclerosis. Rheumatology. 2019; 58: 254-59.

Figure 1.

Correlations of mRSS with ELF score (A) and serum PIIINP (B) and distribution of mRSS among different ELF (C) and PIIINP (D) ranges.

Acknowledgements:

The authors have no acknowledgements to declare.

Disclosure of Interests:

None declared

POS0869 PREDICTIVE VALUE OF ANTI-INTERFERON-INDUCIBLE PROTEIN 16 ANTIBODIES FOR DIGITAL ULCERS OF SYSTEMIC SCLEROSIS

Background:

Interferon-inducible protein 16 (IFI-16) is constitutively expressed in vascular endothelial cells and can inhibit the proliferation of human endothelial cells and the formation of capillary-like structures in vitro. Anti-IFI-16 antibodies were reported in 21%-29% of patients with systemic sclerosis (SSc) and were associated with digital vascular events in a few retrospective studies.

Objectives:

To evaluate the presence and the clinical implication of anti-IFI-16 antibodies in Chinese SSc cohort, focusing on the associations with vasculopathy indexes, and to investigate the predictive value of anti-IFI-16 antibodies for the development of digital ulcers (DUs) in SSc prospectively.

Methods:

Patients with SSc presenting to our center between July 2018 and September 2018 were prospectively enrolled. Serum from 42 SSc patients and 42 age- and sex-matched healthy controls were analyzed for anti-IFI-16 antibodies by enzyme-linked immunosorbent assay (ELISA), and was considered positive if the optical density (OD) value was above the mean OD of controls plus two standard deviations. Tissue immunofluorescence was used to evaluate the expression of IFI16 in skin biopsy samples obtained from SSc patients and normal controls. At baseline, nailfold video-capillaroscopy was performed to assess nailfold capillary density of SSc patients. Power Doppler ultrasound was used to grade finger pulp blood flow (0-no observed flow; 1-decreased flow; 2-normal flow), and to measure ulnar and radial artery blood flow and resistive index (RI). All patients were followed up for 6 months to see whether they experienced new onset or recurrent DUs. The association of anti-IFI-16 antibodies with DUs was analyzed using logistic regression.

Results:

Of the 42 SSc patients, 8 (19.0%) were positive for anti-IFI-16 antibodies. Immunofluorescence of skin biopsy samples from SSc patients exhibited enhanced staining of IFI-16 in the dermis, and colocalization with endothelial marker CD31. SSc patients who were positive for anti-IFI-16 antibodies showed higher ulnar artery RI at baseline (0.95±0.09 vs. 0.86±0.09, p=0.015), while no significant differences were found for other vascular parameters, nor for clinical or demographic profiles. Within 6-month follow-up, 14 (33.3%) patients experienced new-onset or recurrent DUs. Univariate logistic regression revealed the presence of DUs at enrollment (p=0.009), anti-IFI-16 antibody (p=0.012), finger pulp blood flow (p=0.027), and ulnar artery RI (p=0.008) could be the predictors for the development of DUs. Multivariate analysis further identified DUs at enrollment (odds ratio [OR]: 10.85; 95% confidence interval [CI]: 1.61-73.18; p=0.014) and anti-IFI-16 antibody (OR: 15.00; 95% CI: 1.13-199.18; p=0.040) as independent risk factors. Among patients without DUs at enrollment, new-onset ulcers occurred in 80% (4/5) and 4.5% (1/22) of those with and without anti-IFI-16 antibody, respectively (p=0.001).

Conclusion:

Anti-IFI-16 antibody is associated with vasculopathy in SSc and could be used as a novel biomarker for indicating the development of DUs.

References:

[1]McMahan ZH, Shah AA, Vaidya D, et al. Anti-interferon-inducible protein 16 antibodies associate with digital gangrene in patients with Scleroderma. Arthritis Rheumatol. 2016; 68(5): 1262-71.

[2]McMahan ZH, Cottrell TR, Wigley FM, et al. Autoantigens targeted in scleroderma patients with vascular disease are enriched in endothelial lineage cells. Arthritis Rheumatol. 2016; 68(10): 2540–49.

Figure 1.

Multivariate logistic analysis for new or recurrent digital ulcers.

Acknowledgements:

The authors would like to thank Doctor Yi Cheng for performing Power Doppler ultrasound assessment.

Disclosure of Interests:

None declared

High pressure homogenization inactivation of Escherichia coli and Staphylococcus aureus in phosphate buffered saline, milk and apple juice

High pressure homogenization (HPH) offers new opportunities for food pasteurization/sterilization. Escherichia coli and Staphylococcus aureus suspended in phosphate buffered saline (PBS) buffer, milk and apple juice at initial concentration of ~10⁶ log₁₀ CFU per ml were subjected to HPH treatments up to 200 MPa with inlet temperatures at 4-40°C. After HPH at 200 MPa with the inlet temperature at 40°C, the count of E. coli suspended in PBS, milk and apple juice reduced by 3·42, 3·67 and 3·19 log₁₀ CFU per ml respectively while the count of S. aureus decreased by 2·21, 1·02 and 2·33 log₁₀ CFU per ml respectively suggesting that S. aureus was more resistant. The inactivation data were well fitted by the polynomial equation. Milk could provide a protective effect for S. aureus against HPH. After HPH at 200 MPa with the inlet temperature at 20°C, the cell structure of E. coli was destroyed, while no obvious damages were found for S. aureus.

[Identification of a novel HLA-DQB1*03 allele caused by variant of a single nucleotide]

OBJECTIVE

To delineate the characteristics of a novel HLA-DQB1 allele identified during routine HLA matching in a leukemia family.

METHODS

The mother and brother of the patient were subjected to PCR sequence-specific oligonucleotide probe (SSOP), PCR sequence-based typ1ing (SBT), as well as next-generation sequencing (NGS).

RESULTS

PCR-SBT revealed that the patient's mother and brother's HLA-DQB1 sequences did not fully match with any known allele combination. NGS revealed that the novel allele has differed from the closest matched DQB1*03:02 with a T>G substitution at position 233 in exon 2, which resulted in substitution of Valine at codon 46 by Glycine. Pedigree analysis confirmed that the novel HLA-DQB1 allele was inherited from his mother.

CONCLUSION

A novel HLA-DQB1 allele has been identified through next generation sequencing and was officially named as HLA-DQB1*03:362 by the World Health Organization HLA Factor Nomenclature Committee.

Evolution and Diversity of Semaphorins and Plexins in Choanoflagellates

Semaphorins and plexins are cell surface ligand/receptor proteins that affect cytoskeletal dynamics in metazoan cells. Interestingly, they are also present in Choanoflagellata, a class of unicellular heterotrophic flagellates that forms the phylogenetic sister group to Metazoa. Several members of choanoflagellates are capable of forming transient colonies, whereas others reside solitary inside exoskeletons; their molecular diversity is only beginning to emerge. Here, we surveyed genomics data from 22 choanoflagellate species and detected semaphorin/plexin pairs in 16 species. Choanoflagellate semaphorins (Sema-FN1) contain several domain features distinct from metazoan semaphorins, including an N-terminal Reeler domain that may facilitate dimer stabilization, an array of fibronectin type III domains, a variable serine/threonine-rich domain that is a potential site for O-linked glycosylation, and a SEA domain that can undergo autoproteolysis. In contrast, choanoflagellate plexins (Plexin-1) harbor a domain arrangement that is largely identical to metazoan plexins. Both Sema-FN1 and Plexin-1 also contain a short homologous motif near the C-terminus, likely associated with a shared function. Three-dimensional molecular models revealed a highly conserved structural architecture of choanoflagellate Plexin-1 as compared to metazoan plexins, including similar predicted conformational changes in a segment that is involved in the activation of the intracellular Ras-GAP domain. The absence of semaphorins and plexins in several choanoflagellate species did not appear to correlate with unicellular versus colonial lifestyle or ecological factors such as fresh versus salt water environment. Together, our findings support a conserved mechanism of semaphorin/plexin proteins in regulating cytoskeletal dynamics in unicellular and multicellular organisms.

Diversified transcriptional responses of myeloid and glial cells in spinal cord injury shaped by HDAC3 activity

The innate immune response influences neural repair after spinal cord injury (SCI). Here, we combined myeloid-specific transcriptomics and single-cell RNA sequencing to uncover not only a common core but also temporally distinct gene programs in injury-activated microglia and macrophages (IAM). Intriguingly, we detected a wide range of microglial cell states even in healthy spinal cord. Upon injury, IAM progressively acquired overall reparative, yet diversified transcriptional profiles, each comprising four transcriptional subtypes with specialized tasks. Notably, IAM have both distinct and common gene signatures as compared to neurodegeneration-associated microglia, both engaging phagocytosis, autophagy, and TyroBP pathways. We also identified an immediate response microglia subtype serving as a source population for microglial transformation and a proliferative subtype controlled by the epigenetic regulator histone deacetylase 3 (HDAC3). Together, our data unveil diversification of myeloid and glial subtypes in SCI and an extensive influence of HDAC3, which may be exploited to enhance functional recovery.

Plexin-B2 facilitates glioblastoma infiltration by modulating cell biomechanics

Infiltrative growth is a major cause of high lethality of malignant brain tumors such as glioblastoma (GBM). We show here that GBM cells upregulate guidance receptor Plexin-B2 to gain invasiveness. Deletion of Plexin-B2 in GBM stem cells limited tumor spread and shifted invasion paths from axon fiber tracts to perivascular routes. On a cellular level, Plexin-B2 adjusts cell adhesiveness, migratory responses to different matrix stiffness, and actomyosin dynamics, thus empowering GBM cells to leave stiff tumor bulk and infiltrate softer brain parenchyma. Correspondingly, gene signatures affected by Plexin-B2 were associated with locomotor regulation, matrix interactions, and cellular biomechanics. On a molecular level, the intracellular Ras-GAP domain contributed to Plexin-B2 function, while the signaling relationship with downstream effectors Rap1/2 appeared variable between GBM stem cell lines, reflecting intertumoral heterogeneity. Our studies establish Plexin-B2 as a modulator of cell biomechanics that is usurped by GBM cells to gain invasiveness.

Granular Cell Tumor: A Technical Approach for Resection of a Rare Suprasellar Mass

BACKGROUND AND IMPORTANCE

Granular cell tumors (GCTs) of the sellar and suprasellar regions are rare tumors that may be managed surgically by multiple strategies. The technical approaches for these tumors have rarely been described in the literature.

CLINICAL PRESENTATION

We introduce the case of a patient presenting with dizziness and headaches who was found to have a suprasellar and retrochiasmatic mass and eventually underwent surgical resection. We discuss the characteristics of this tumor, and the current state of the literature. Also included are details regarding the surgical approach utilized in this case, and a discussion of the various surgical approaches for this type of tumor.

CONCLUSION

There are several approaches for the surgical resection of suprasellar GCTs, and the approach utilized may depend on patient and/or surgeon considerations. Patient-specific considerations must be made to ensure maximal safe resection of these lesions.