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1.
Science ; 384(6695): 573-579, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38696577

ABSTRACT

Neurons on the left and right sides of the nervous system often show asymmetric properties, but how such differences arise is poorly understood. Genetic screening in zebrafish revealed that loss of function of the transmembrane protein Cachd1 resulted in right-sided habenula neurons adopting left-sided identity. Cachd1 is expressed in neuronal progenitors, functions downstream of asymmetric environmental signals, and influences timing of the normally asymmetric patterns of neurogenesis. Biochemical and structural analyses demonstrated that Cachd1 can bind simultaneously to Lrp6 and Frizzled family Wnt co-receptors. Consistent with this, lrp6 mutant zebrafish lose asymmetry in the habenulae, and epistasis experiments support a role for Cachd1 in modulating Wnt pathway activity in the brain. These studies identify Cachd1 as a conserved Wnt receptor-interacting protein that regulates lateralized neuronal identity in the zebrafish brain.


Subject(s)
Habenula , Neurogenesis , Neurons , Wnt Signaling Pathway , Zebrafish Proteins , Zebrafish , Animals , Zebrafish/genetics , Zebrafish Proteins/metabolism , Zebrafish Proteins/genetics , Habenula/metabolism , Habenula/embryology , Neurons/metabolism , Low Density Lipoprotein Receptor-Related Protein-6/metabolism , Low Density Lipoprotein Receptor-Related Protein-6/genetics , Frizzled Receptors/metabolism , Frizzled Receptors/genetics , Receptors, Wnt/metabolism , Receptors, Wnt/genetics , Brain/metabolism , Loss of Function Mutation , Membrane Proteins/metabolism , Membrane Proteins/genetics
2.
Crit Rev Oncol Hematol ; 198: 104359, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38615871

ABSTRACT

Ferroptosis is an unconventional programmed cell death mode caused by phospholipid peroxidation dependent on iron. Emerging immunotherapies (especially immune checkpoint inhibitors) have the potential to enhance lung cancer patients' long-term survival. Although immunotherapy has yielded significant positive applications in some patients, there are still many mechanisms that can cause lung cancer cells to evade immunity, thus leading to the failure of targeted therapies. Immune-tolerant cancer cells are insensitive to conventional death pathways such as apoptosis and necrosis, whereas mesenchymal and metastasis-prone cancer cells are particularly vulnerable to ferroptosis, which plays a vital role in mediating immune tolerance resistance by tumors and immune cells. As a result, triggering lung cancer cell ferroptosis holds significant therapeutic potential for drug-resistant malignancies. Here, we summarize the mechanisms underlying the suppression of ferroptosis in lung cancer, highlight its function in the lung cancer immune microenvironment, and propose possible therapeutic strategies.

3.
Cancer Med ; 13(3): e6855, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38214075

ABSTRACT

BACKGROUND: The development of immune checkpoint inhibitors has made a significant breakthrough in the treatment of non-small-cell lung cancer (NSCLC). However, there remains a huge unmet clinical need for patients with acquired resistance after initial treatment response. METHODS: This study evaluated the combination of IBI310 (an anti-cytotoxic T lymphocyte-associated antigen-4 [CTLA-4] antibody) and sintilimab (an anti-programmed death 1 [PD-1]) antibody) in NSCLC patients who have previously been treated with anti-PD-1/ligand (L)1 and acquired resistance. The patients were randomly assigned to receive either a lower dose of IBI310 (1 mg/kg Q3W, cohort A) or a higher dose of IBI310 (3 mg/kg Q3W, cohort B) in combination with sintilimab (200 mg Q3W). The primary endpoints of the study were objective response rate (ORR) assessed by RECISTv1.1 and safety, while secondary endpoints included disease control rate (DCR), progression-free survival (PFS), and overall survival (OS). RESULTS: As of November 2, 2023, the study had enrolled 30 patients, with 15 patients in each cohort. The ORR was 13.3% (2/15, 95% confidence interval [CI], 1.7-40.5) in cohort B. DCR were 46.7% (95% CI, 21.3-73.4) and 66.7% (95% CI, 38.4-88.2) in cohorts A and B, respectively. In cohorts A and B of this trial, the median follow-up times were 4.2 and 5.6 months, respectively. Median PFS was 1.45 (95% CI, 1.35-2.73) versus 2.73 (95% CI, 1.41-4.90) months for cohort A versus B; the median OS was 7.03 (95% CI, 3.09-not calculable [NC]) months in cohort A and 8.90 (95% CI, 5.13-NC) months in cohort B. Of the 30 patients, 86.7% in both cohorts experienced treatment-related adverse events (TRAEs) with Grade ≥3 TRAEs occurring in 40% and 53.3% of patients in cohorts A and B, respectively. CONCLUSION: IBI310 3 mg/kg Q3W plus sintilimab was effective in a small number of previously treated anti-PD-1/L1-resistant NSCLC patients.


Subject(s)
Antineoplastic Agents , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Antibodies, Monoclonal , Antibodies, Monoclonal, Humanized/adverse effects , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy
4.
Crit Rev Oncol Hematol ; 190: 104105, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37598896

ABSTRACT

Cancer stem cells (CSCs), a small population of stem cells existing in cancer cells, are considered as the "culprits" of tumor recurrence, metastasis, and drug resistance. Ferroptosis is a promising new lead in anti-cancer therapy. Because of unique metabolic characteristics, CSCs' growth is more dependent on the iron and lipid than ordinary cancer cells. When the metabolism of iron/lipid is disordered, that is, imbalanced redox homeostasis, CSCs are more susceptible to ferroptosis. The expression of Nuclear factor E2-related factor 2 (Nrf2), a molecule playing a major regulatory role in redox homeostasis, determines whether the cells are under oxidative stress and ferroptosis occurs. Nrf2 expression level is higher in CSCs, indicating stronger dependence on Nrf2. Here we expound the unique biological and metabolic characteristics of CSCs, explore the mechanism of inducing ferroptosis by targeting Nrf2, thus providing promising new targets for eliminating aggressive tumors and achieving the goal of curing tumors.


Subject(s)
Ferroptosis , Neoplasms , Humans , NF-E2-Related Factor 2 , Neoplastic Stem Cells , Iron , Lipids
5.
J Vis ; 23(6): 2, 2023 06 01.
Article in English | MEDLINE | ID: mdl-37266933

ABSTRACT

Most studies on the perception of style have used whole scenes/entire paintings; in our study, we isolated a single motif (an apple) to reduce or even eliminate the influence of composition, iconography, and other contextual information. In this article, we empirically address two fundamental questions of the existence (Experiment 1) and description (Experiment 2) of style. We chose 48 cut-outs of mostly Western European paintings (15th to 21st century) that showed apples. In Experiment 1, 415 unique participants completed online triplet similarity tasks. Multidimensional scaling (MDS) reached a nonrandom three-dimensional (3D) embedding, showing that participants are able to judge stylistic differences in a systematic way. We also found a strong correlation between creation year and embedding, both a linear correlation with Dimension 2, and a rotational correlation in the first two dimensions. To interpret the embedding further, in Experiment 2, we fitted three color statistics and nine attribute ratings (glossiness, three-dimensionality, convincingness, brush coarseness, etc.) to the 3D perceptual style space. Results showed that Dimension 1 is associated with spatial attributes (Smoothness, Brushstroke coarseness) and Convincingness, Dimension 2 is related to Hue, and Dimension 3 is related to Chroma. The results suggest that texture and color are two important variables for style perception. By isolating the motifs, we could exclude higher levels of information such as composition and context. Interestingly, the results reinforce previous findings using whole scenes, suggesting that style can already be perceived in sometimes very small fragments of paintings.


Subject(s)
Paintings , Humans , Perception
6.
Crit Rev Oncol Hematol ; 188: 104064, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37379960

ABSTRACT

In recent years, the indications for immunotherapy in cancer treatment have been expanding. The increased risk of cancer in young people, coupled with the fact that many women or men choose to delay childbearing, has made an increasing number of patients of childbearing age eligible for immunotherapy. Furthermore, with the improvements of various treatments, more young people and children are able to survive cancer. As a result, long-term sequelae of cancer treatments, such as reproductive dysfunction, are increasingly important for survivors. While many anti-cancer drugs are known to cause reproduction dysfunction, the effects of immune checkpoint inhibitors (ICIs) on reproduction function remain largely unknown. Through a retrospective analysis of previous reports and literature, this article aims to elucidate the causes of reproductive dysfunction induced by ICIs and focus on their specific mechanisms, in order to providing some guidance to clinicians and patients.


Subject(s)
Antineoplastic Agents , Neoplasms , Male , Child , Humans , Female , Adolescent , Immune Checkpoint Inhibitors/therapeutic use , Retrospective Studies , Antineoplastic Agents/therapeutic use , Immunotherapy/adverse effects
7.
Eur J Med Chem ; 251: 115132, 2023 May 05.
Article in English | MEDLINE | ID: mdl-36934521

ABSTRACT

N-Acyl indolines 4 are potent, non-covalent Notum inhibitors developed from a covalent virtual screening hit 2a. The lead compounds were simple to synthesise, achieved excellent potency in a biochemical Notum-OPTS assay and restored Wnt signalling in a cell-based TCF/LEF reporter assay. Multiple high resolution X-ray structures established a common binding mode of these inhibitors with the indoline bound centred in the palmiteolate pocket with key interactions being aromatic stacking and a water mediated hydrogen bond to the oxyanion hole. These N-acyl indolines 4 will be useful tools for use in vitro studies to investigate the role of Notum in disease models, especially when paired with a structurally related covalent inhibitor (e.g. 4w and 2a). Overall, this study highlights the designed switch from covalent to non-covalent Notum inhibitors and so illustrates a complementary approach for hit generation and target inhibition.


Subject(s)
Carboxylic Ester Hydrolases , Wnt Signaling Pathway , Biophysical Phenomena
8.
Viruses ; 14(12)2022 11 24.
Article in English | MEDLINE | ID: mdl-36560629

ABSTRACT

Echoviruses, for which there are currently no approved vaccines or drugs, are responsible for a range of human diseases, for example echovirus 11 (E11) is a major cause of serious neonatal morbidity and mortality. Decay-accelerating factor (DAF, also known as CD55) is an attachment receptor for E11. Here, we report the structure of the complex of E11 and the full-length ectodomain of DAF (short consensus repeats, SCRs, 1-4) at 3.1 Å determined by cryo-electron microscopy (cryo-EM). SCRs 3 and 4 of DAF interact with E11 at the southern rim of the canyon via the VP2 EF and VP3 BC loops. We also observe an unexpected interaction between the N-linked glycan (residue 95 of DAF) and the VP2 BC loop of E11. DAF is a receptor for at least 20 enteroviruses and we classify its binding patterns from reported DAF/virus complexes into two distinct positions and orientations, named as E6 and E11 poses. Whilst 60 DAF molecules can attach to the virion in the E6 pose, no more than 30 can attach to E11 due to steric restrictions. Analysis of the distinct modes of interaction and structure and sequence-based phylogenies suggests that the two modes evolved independently, with the E6 mode likely found earlier.


Subject(s)
Enterovirus Infections , Enterovirus , Infant, Newborn , Humans , Cryoelectron Microscopy , CD55 Antigens , Enterovirus/metabolism , Enterovirus B, Human/metabolism
9.
Front Immunol ; 13: 1074906, 2022.
Article in English | MEDLINE | ID: mdl-36569881

ABSTRACT

This pilot study (NCT03958097; https://www.clinicaltrials.gov/ct2/show/NCT03958097) was aimed to evaluate the efficacy and safety of PD-1 antibody combined autologous NK cells in the treatment of patients with stage IIIB/IIIC or IV non-small-cell lung cancer (NSCLC) who failed the first-line platinum-based chemotherapy. All patients received both sintilimab 200mg and 3×109 NK cells every 3 weeks. 20 patients were enrolled, median follow up time was 22.6 months. The median PFS was 11.6 months, ORR was 45%. Median OS was 17.7 months, 6-month OS rate and 12-month OS rate was 95.0% and 80.0%. Unexpected adverse events were not observed. 2 patients reported grade 3 adverse events (hypertriglyceridemia, neutropenia and increased creatine kinase). The autologous NK cells did not add extra adverse events to the ICI treatment. Autologous NK plus sintilimab showed promising antitumor activity and an acceptable safety profile in advanced driven-mutation negative NSCLC who failed on the first line treatment.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/drug therapy , Killer Cells, Natural/pathology , Lung Neoplasms/drug therapy , Pilot Projects , Platinum/therapeutic use
10.
J Inflamm Res ; 15: 6801-6812, 2022.
Article in English | MEDLINE | ID: mdl-36575747

ABSTRACT

Colorectal cancer (CRC) has been one of the most common cancers and maintains the second-highest incidence and mortality rates among all cancers. The high risk of recurrence and metastasis and poor survival are still huge challenges in CRC therapy, in which the discovery of ferroptosis provides a novel perspective. It has been ten years since a unique type of regulated cell death driven by iron accumulation and lipid peroxidation was proposed and named ferroptosis. During the past decade, there have been multiple pieces of evidence suggesting that ferroptosis participates in the pathophysiological processes during disease progression. In this review, we describe ferroptosis as an imbalance of oxidant systems and anti-oxidants which results in lipid peroxidation, membrane damage, and finally cell death. We elaborate on the mechanisms of ferroptosis and systematically summarize recent studies on the regulatory pathways of ferroptosis in CRC from various perspectives, ranging from encoding genes, noncoding RNAs to regulatory proteins. Finally, we discuss the potential therapeutic role of ferroptosis in CRC treatments.

11.
Sci Rep ; 12(1): 14850, 2022 09 01.
Article in English | MEDLINE | ID: mdl-36050373

ABSTRACT

Sizzled (Szl) is both a secreted frizzled related protein (sFRP) and a naturally occurring inhibitor of the zinc metalloproteinase bone morphogenetic protein-1 (BMP-1), a key regulator of extracellular matrix assembly and growth factor activation. Here we present a new crystal structure for Szl which differs from that previously reported by a large scale (90°) hinge rotation between its cysteine-rich and netrin-like domains. We also present results of a molecular docking analysis showing interactions likely to be involved in the inhibition of BMP-1 activity by Szl. When compared with known structures of BMP-1 in complex with small molecule inhibitors, this reveals features that may be helpful in the design of new inhibitors to prevent the excessive accumulation of extracellular matrix that is the hallmark of fibrotic diseases.


Subject(s)
Intercellular Signaling Peptides and Proteins , Xenopus Proteins , Bone Morphogenetic Protein 1/metabolism , Bone Morphogenetic Protein 2/metabolism , Bone Morphogenetic Protein 7/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Molecular Docking Simulation , Protein Binding , Xenopus Proteins/metabolism
12.
Arthritis Res Ther ; 24(1): 214, 2022 09 06.
Article in English | MEDLINE | ID: mdl-36068615

ABSTRACT

BACKGROUND: To identify regulatory ncRNA molecules that can cause differential expression of CDH2 in intervertebral disc degeneration (IDD) and explore whether there are other ways to affect the progression of IDD. METHODS: A primary culture of human nucleus pulposus (NP) cells was established and identified by immunofluorescence. An in vitro IDD model was constructed by compressing human NP cells, and the MTT assay was used to measure cell viability. Changes in the ncRNA group were analysed by RNA-seq. The expression levels of hsa_circ_7042, CDH2, and miR-369-3p were detected by qPCR. Cell apoptosis, senescence, and extracellular matrix (ECM) metabolism were detected by flow cytometry, ß-galactosidase staining, and Western blotting. hsa_circ_7042, miR-369-3p, and bone morphogenetic protein 2 (BMP2) were verified by luciferase and RNA immunoprecipitation (RIP) analyses. The PI3K/Akt pathway was validated by transfection of BMP2 siRNA. Furthermore, a mouse model of lumbar spine instability was constructed. circ_7042 adenovirus was packaged and injected into the intervertebral discs of mice, and the influence of circ_7042 overexpression on intervertebral disc degeneration was determined. RESULTS: Western blotting, qPCR, and flow cytometry analyses confirmed that overexpression of circ_7042 could downregulate miR-369-3p and upregulate the expression of CDH2 and BMP2 in IDD cell and animal models. Additionally, the levels of apoptotic and senescent cells decreased, and ECM degradation decreased. The PI3K/Akt pathway was significantly activated after circ_7042 was overexpressed. The injection of circ_7042-overexpressing adenovirus effectively reduced ECM degradation and the level of apoptosis in NP tissue. CONCLUSIONS: circ_7042 could upregulate the expression of CDH2 and BMP2 by absorbing miR-369-3p, and the increased BMP2 activated the PI3K/Akt pathway, thus improving IDD.


Subject(s)
Intervertebral Disc Degeneration , MicroRNAs , Animals , Apoptosis/genetics , Bone Morphogenetic Protein 2 , Humans , Intervertebral Disc Degeneration/genetics , Intervertebral Disc Degeneration/metabolism , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt/metabolism
13.
Nat Commun ; 13(1): 5022, 2022 08 26.
Article in English | MEDLINE | ID: mdl-36028489

ABSTRACT

Signaling by the human C-type lectin-like receptor, natural killer (NK) cell inhibitory receptor NKR-P1, has a critical role in many immune-related diseases and cancer. C-type lectin-like receptors have weak affinities to their ligands; therefore, setting up a comprehensive model of NKR-P1-LLT1 interactions that considers the natural state of the receptor on the cell surface is necessary to understand its functions. Here we report the crystal structures of the NKR-P1 and NKR-P1:LLT1 complexes, which provides evidence that NKR-P1 forms homodimers in an unexpected arrangement to enable LLT1 binding in two modes, bridging two LLT1 molecules. These interaction clusters are suggestive of an inhibitory immune synapse. By observing the formation of these clusters in solution using SEC-SAXS analysis, by dSTORM super-resolution microscopy on the cell surface, and by following their role in receptor signaling with freshly isolated NK cells, we show that only the ligation of both LLT1 binding interfaces leads to effective NKR-P1 inhibitory signaling. In summary, our findings collectively support a model of NKR-P1:LLT1 clustering, which allows the interacting proteins to overcome weak ligand-receptor affinity and to trigger signal transduction upon cellular contact in the immune synapse.


Subject(s)
Killer Cells, Natural , Receptors, Cell Surface , Antigens, Surface , Cluster Analysis , Humans , Lectins, C-Type , Ligands , NK Cell Lectin-Like Receptor Subfamily B , Scattering, Small Angle , Synapses , X-Ray Diffraction
14.
ACS Chem Neurosci ; 13(13): 2060-2077, 2022 07 06.
Article in English | MEDLINE | ID: mdl-35731924

ABSTRACT

The Wnt signaling suppressor Notum is a promising target for osteoporosis, Alzheimer's disease, and colorectal cancers. To develop novel Notum inhibitors, we used an X-ray crystallographic fragment screen with the Diamond-SGC Poised Library (DSPL) and identified 59 fragment hits from the analysis of 768 data sets. Fifty-eight of the hits were found bound at the enzyme catalytic pocket with potencies ranging from 0.5 to >1000 µM. Analysis of the fragments' diverse binding modes, enzymatic inhibitory activities, and chemical properties led to the selection of six hits for optimization, and five of these resulted in improved Notum inhibitory potencies. One hit, 1-phenyl-1,2,3-triazole 7, and its related cluster members, have shown promising lead-like properties. These became the focus of our fragment development activities, resulting in compound 7d with IC50 0.0067 µM. The large number of Notum fragment structures and their initial optimization provided an important basis for further Notum inhibitor development.


Subject(s)
Crystallography, X-Ray
15.
J Med Chem ; 65(10): 7212-7230, 2022 05 26.
Article in English | MEDLINE | ID: mdl-35536179

ABSTRACT

Notum is a carboxylesterase that suppresses Wnt signaling through deacylation of an essential palmitoleate group on Wnt proteins. There is a growing understanding of the role Notum plays in human diseases such as colorectal cancer and Alzheimer's disease, supporting the need to discover improved inhibitors, especially for use in models of neurodegeneration. Here, we have described the discovery and profile of 8l (ARUK3001185) as a potent, selective, and brain-penetrant inhibitor of Notum activity suitable for oral dosing in rodent models of disease. Crystallographic fragment screening of the Diamond-SGC Poised Library for binding to Notum, supported by a biochemical enzyme assay to rank inhibition activity, identified 6a and 6b as a pair of outstanding hits. Fragment development of 6 delivered 8l that restored Wnt signaling in the presence of Notum in a cell-based reporter assay. Assessment in pharmacology screens showed 8l to be selective against serine hydrolases, kinases, and drug targets.


Subject(s)
Enzyme Inhibitors , Esterases , Brain/metabolism , Crystallography, X-Ray , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Esterases/metabolism , Wnt Signaling Pathway
16.
Cereb Cortex ; 33(1): 135-151, 2022 12 15.
Article in English | MEDLINE | ID: mdl-35388407

ABSTRACT

Neural-vascular coupling (NVC) is the process by which oxygen and nutrients are delivered to metabolically active neurons by blood vessels. Murine models of NVC disruption have revealed its critical role in healthy neural function. We hypothesized that, in humans, aging exerts detrimental effects upon the integrity of the neural-glial-vascular system that underlies NVC. To test this hypothesis, calibrated functional magnetic resonance imaging (cfMRI) was used to characterize age-related changes in cerebral blood flow (CBF) and oxygen metabolism during visual cortex stimulation. Thirty-three younger and 27 older participants underwent cfMRI scanning during both an attention-controlled visual stimulation task and a hypercapnia paradigm used to calibrate the blood-oxygen-level-dependent signal. Measurement of stimulus-evoked blood flow and oxygen metabolism permitted calculation of the NVC ratio to assess the integrity of neural-vascular communication. Consistent with our hypothesis, we observed monotonic NVC ratio increases with increasing visual stimulation frequency in younger adults but not in older adults. Age-related changes in stimulus-evoked cerebrovascular and neurometabolic signal could not fully explain this disruption; increases in stimulus-evoked neurometabolic activity elicited corresponding increases in stimulus-evoked CBF in younger but not in older adults. These results implicate age-related, demand-dependent failures of the neural-glial-vascular structures that comprise the NVC system.


Subject(s)
Neurovascular Coupling , Humans , Animals , Mice , Aged , Neurovascular Coupling/physiology , Brain/diagnostic imaging , Brain/metabolism , Cerebrovascular Circulation/physiology , Magnetic Resonance Imaging/methods , Aging/physiology , Oxygen
17.
Sci Total Environ ; 820: 153196, 2022 May 10.
Article in English | MEDLINE | ID: mdl-35063526

ABSTRACT

As high impact weather in a large scale, typhoon movement from the northwest Pacific into inland regions influencing ambient O3 changes is unclear, especially in North China Plain (NCP). A landing Typhoon Ampil during July 17-24, 2018 was studied herein to characterize the surface O3 anomalies during its movement over NCP. Landing typhoons present large negative O3 anomalies at the center of the typhoon and positive O3 anomalies 600-1700 km away from the center. During the northwest movement of Typhoon Ampil to the NCP, the area and magnitude of both positive and negative O3 anomalies shrank, particularly in the western and northern periphery, where the typical diurnal change of O3 dissipated with nocturnal O3 enhancement in the NCP. The spatiotemporal patterns of surface O3 anomalies in the NCP were induced significantly during various stages of typhoon movement with a stable structure in the atmospheric boundary layer, strong solar radiation on sunny days, and stratosphere-to-troposphere transport (STT) in the typhoon periphery, depending on the changing intensity, distance, and orientation of the typhoon center. Among them, the STT played a considerable role and contributed 32% to the positive anomalies of surface O3 in the NCP. Under the influence of westerly jets and high pressure at mid-latitudes on the typhoon movement, strong wind convergences in the upper troposphere were formed intensifying the downdraft of O3-rich stratospheric air to the boundary layer in the NCP with an asymmetrical distribution of surface positive O3 anomalies over the periphery of typhoon. This study could improve our understanding of regional ozone changes with meteorological influences.


Subject(s)
Air Pollutants , Air Pollution , Cyclonic Storms , Ozone , Air Pollutants/analysis , Air Pollution/analysis , China , Environmental Monitoring , Ozone/analysis
18.
Theranostics ; 12(1): 1-17, 2022.
Article in English | MEDLINE | ID: mdl-34987630

ABSTRACT

Background: Administration of potent anti-receptor-binding domain (RBD) monoclonal antibodies has been shown to curtail viral shedding and reduce hospitalization in patients with SARS-CoV-2 infection. However, the structure-function analysis of potent human anti-RBD monoclonal antibodies and its links to the formulation of antibody cocktails remains largely elusive. Methods: Previously, we isolated a panel of neutralizing anti-RBD monoclonal antibodies from convalescent patients and showed their neutralization efficacy in vitro. Here, we elucidate the mechanism of action of antibodies and dissect antibodies at the epitope level, which leads to a formation of a potent antibody cocktail. Results: We found that representative antibodies which target non-overlapping epitopes are effective against wild type virus and recently emerging variants of concern, whilst being encoded by antibody genes with few somatic mutations. Neutralization is associated with the inhibition of binding of viral RBD to ACE2 and possibly of the subsequent fusion process. Structural analysis of representative antibodies, by cryo-electron microscopy and crystallography, reveals that they have some unique aspects that are of potential value while sharing some features in common with previously reported neutralizing monoclonal antibodies. For instance, one has a common VH 3-53 public variable region yet is unusually resilient to mutation at residue 501 of the RBD. We evaluate the in vivo efficacy of an antibody cocktail consisting of two potent non-competing anti-RBD antibodies in a Syrian hamster model. We demonstrate that the cocktail prevents weight loss, reduces lung viral load and attenuates pulmonary inflammation in hamsters in both prophylactic and therapeutic settings. Although neutralization of one of these antibodies is abrogated by the mutations of variant B.1.351, it is also possible to produce a bi-valent cocktail of antibodies both of which are resilient to variants B.1.1.7, B.1.351 and B.1.617.2. Conclusions: These findings support the up-to-date and rational design of an anti-RBD antibody cocktail as a therapeutic candidate against COVID-19.


Subject(s)
Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/pharmacology , COVID-19 Drug Treatment , SARS-CoV-2/metabolism , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/metabolism , Animals , Antibodies, Monoclonal/metabolism , Antibodies, Neutralizing/chemistry , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/pharmacology , Binding Sites , Binding, Competitive , COVID-19/virology , Cricetinae , Cryoelectron Microscopy , Crystallography, X-Ray , Dogs , Epitopes , Female , Humans , Madin Darby Canine Kidney Cells , Neutralization Tests , Protein Domains , SARS-CoV-2/genetics , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism
19.
Open Med (Wars) ; 17(1): 53-60, 2022.
Article in English | MEDLINE | ID: mdl-34993345

ABSTRACT

Clinical treatment is challenging for elderly patients with lung cancer who cannot tolerate chemotherapy, do not have cancer driver genes, and have low expression of PD-L1. Since these patients are usually excluded from clinical studies, evidence-based medicine supporting the use of immunotherapy is lacking. Considering the potentially limited clinical benefits and high associated risk of hyperprogressive disease, determining an appropriate treatment is an urgent clinical challenge. We report a 71 year-old male patient diagnosed with advanced lung adenocarcinoma lacking key driving genes (EGFR, ALK, and ROS-1), and low expression of PD-L1 on tumor cells (10-15%). The tumor tissue showed a low level of microsatellite instability, low tumor mutational burden, and no DNA mismatch repair deficiency on whole-exome sequencing (WES). However, a high blood tumor mutational burden was detected. After considering the biomarkers of therapeutic effect and ruling out the risk of hyperprogressive disease, pembrolizumab 200 mg was administered every 3 weeks for a year (17 cycles). The disease remained stable for >39 months, and adverse effects were mild and well-tolerated. Therefore, a comprehensive biomarker evaluation, especially in elderly patients lacking driving genes, is essential. Liquid biopsy technology and WES may be useful for overcoming the limitations of tissue biopsy.

20.
Cell Host Microbe ; 30(1): 53-68.e12, 2022 01 12.
Article in English | MEDLINE | ID: mdl-34921776

ABSTRACT

Alpha-B.1.1.7, Beta-B.1.351, Gamma-P.1, and Delta-B.1.617.2 variants of SARS-CoV-2 express multiple mutations in the spike protein (S). These may alter the antigenic structure of S, causing escape from natural or vaccine-induced immunity. Beta is particularly difficult to neutralize using serum induced by early pandemic SARS-CoV-2 strains and is most antigenically separated from Delta. To understand this, we generated 674 mAbs from Beta-infected individuals and performed a detailed structure-function analysis of the 27 most potent mAbs: one binding the spike N-terminal domain (NTD), the rest the receptor-binding domain (RBD). Two of these RBD-binding mAbs recognize a neutralizing epitope conserved between SARS-CoV-1 and -2, while 18 target mutated residues in Beta: K417N, E484K, and N501Y. There is a major response to N501Y, including a public IgVH4-39 sequence, with E484K and K417N also targeted. Recognition of these key residues underscores why serum from Beta cases poorly neutralizes early pandemic and Delta viruses.


Subject(s)
Antibodies, Viral/immunology , Antibody Formation/immunology , COVID-19/immunology , SARS-CoV-2/immunology , Animals , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Cells, Cultured , Chlorocebus aethiops , Female , HEK293 Cells , Humans , Male , Mice , Mice, Transgenic , Neutralization Tests/methods , Protein Binding/immunology , Spike Glycoprotein, Coronavirus/immunology , Vero Cells
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