CRISPR editing demonstrates rs10490924 raised oxidative stress in iPSC-derived retinal cells from patients with ARMS2/HTRA1-related AMD.

Genome-wide association studies (GWAS) have identified genetic risk loci for age-related macular degeneration (AMD) on the chromosome 10q26 (Chr10) locus and are tightly linked: the A69S (G>T) rs10490924 single-nucleotide variant (SNV) and the AATAA-rich insertion-deletion (indel, del443/ins54), which are found in the age-related maculopathy susceptibility 2 (ARMS2) gene, and the G512A (G>A) rs11200638 SNV, which is found in the high-temperature requirement A serine peptidase 1 (HTRA1) promoter. The fourth variant is Y402H complement factor H (CFH), which directs CFH signaling. CRISPR manipulation of retinal pigment epithelium (RPE) cells may allow one to isolate the effects of the individual SNV and thus identify SNV-specific effects on cell phenotype. Clustered regularly interspaced short palindromic repeats (CRISPR) editing demonstrates that rs10490924 raised oxidative stress in induced pluripotent stem cell (iPSC)-derived retinal cells from patients with AMD. Sodium phenylbutyrate preferentially reverses the cell death caused by ARMS2 rs10490924 but not HTRA1 rs11200638. This study serves as a proof of concept for the use of patient-specific iPSCs for functional annotation of tightly linked GWAS to study the etiology of a late-onset disease phenotype. More importantly, we demonstrate that antioxidant administration may be useful for reducing reactive oxidative stress in AMD, a prevalent late-onset neurodegenerative disorder.

Impaired cholesterol efflux in retinal pigment epithelium of individuals with juvenile macular degeneration.

Macular degeneration (MD) is characterized by the progressive deterioration of the macula and represents one of the most prevalent causes of blindness worldwide. Abnormal intracellular accumulation of lipid droplets and pericellular deposits of lipid-rich material in the retinal pigment epithelium (RPE) called drusen are clinical hallmarks of different forms of MD including Doyne honeycomb retinal dystrophy (DHRD) and age-related MD (AMD). However, the appropriate molecular therapeutic target underlying these disorder phenotypes remains elusive. Here, we address this knowledge gap by comparing the proteomic profiles of induced pluripotent stem cell (iPSC)-derived RPEs (iRPE) from individuals with DHRD and their isogenic controls. Our analysis and follow-up studies elucidated the mechanism of lipid accumulation in DHRD iRPE cells. Specifically, we detected significant downregulation of carboxylesterase 1 (CES1), an enzyme that converts cholesteryl ester to free cholesterol, an indispensable process in cholesterol export. CES1 knockdown or overexpression of EFEMP1R345W, a variant of EGF-containing fibulin extracellular matrix protein 1 that is associated with DHRD and attenuated cholesterol efflux and led to lipid droplet accumulation. In iRPE cells, we also found that EFEMP1R345W has a hyper-inhibitory effect on epidermal growth factor receptor (EGFR) signaling when compared to EFEMP1WT and may suppress CES1 expression via the downregulation of transcription factor SP1. Taken together, these results highlight the homeostatic role of cholesterol efflux in iRPE cells and identify CES1 as a mediator of cholesterol efflux in MD.

Identification and Characterization of Pectate Lyase as a Novel Allergen in Artemisia sieversiana Pollen.

INTRODUCTION: Artemisia species are widely spread in north hemisphere. Artemisia sieversiana pollen is one of the common pollen allergens in the north of China. At present, seven allergens were identified and had been listed officially from A. sieversiana pollen, but the remaining allergens are still insufficiently studied, which need to be found. METHODS: Pectate lyase was purified from the extracts of A. sieversiana pollen by anion exchange, size exclusion, and HPLC-hydrophobic interaction chromatography. The gene of A. sieversiana pectate lyase (Art si pectate lyase) was cloned and expressed in Escherichia coli. The enzyme activity and circular dichroism (CD) spectrum of natural and recombinant proteins were analyzed. The allergenicity of Art si pectate lyase was characterized by enzyme-linked immunosorbent assay (ELISA), Western blot, inhibition ELISA, and basophil activation test. The allergen's physicochemical properties, three-dimensional structure, sequence profiles with homologous allergens and phylogenetic tree were analyzed by in silico methods. RESULTS: Natural Art si pectate lyase (nArt si pectate lyase) was purified from A. sieversiana pollen extracts by three chromatographic strategies. The cDNA sequence of Art si pectate lyase had a 1191-bp open reading frame encoding 396 amino acids. Both natural and recombinant pectate lyase (rArt si pectate lyase) exhibited similar CD spectrum, and nArt si pectate lyase had higher enzymatic activity. Moreover, the specific immunoglobulin E (IgE) binding rate against nArt si pectate lyase and rArt si pectate lyase was determined as 40% (6/15) in patients' serum with Artemisia species pollen allergy by ELISA. The nArt si pectate lyase and rArt si pectate lyase could inhibit 76.11% and 47.26% of IgE binding activities to the pollen extracts, respectively. Art si pectate lyase was also confirmed to activate patients' basophils. Its structure contains a predominant motif of classic parallel helical core, consisting of three parallel ß-sheets, and two highly conserved features (vWiDH, RxPxxR) which may contribute to pectate lyase activity. Moreover, Art si pectate lyase shared the highest sequence identity of 73.0% with Art v 6 among currently recognized pectate lyase allergen, both were clustered into the same branch in the phylogenetic tree. CONCLUSION: In this study, pectate lyase was identified and comprehensively characterized as a novel allergen in A. sieversiana pollen. The findings enriched the allergen information for this pollen and promoted the development of component-resolved diagnosis and molecular therapy of A. sieversiana pollen allergy.

Comparison of embryo quality and pregnancy outcomes for patients with low ovarian reserve in natural cycles and mildly stimulated cycles: a cohort study.

BACKGROUND: As women with low ovarian reserve embark on the challenging journey of in-vitro fertilisation (IVF) treatment, the choice between natural and mildly stimulated cycles becomes a pivotal consideration. It is unclear which of these two regimens is superior for women with low ovarian reserve. Our study aims to assess the impact of natural cycles on embryo quality and pregnancy outcomes in women with low ovarian reserve undergoing IVF treatment compared to mildly stimulated cycles. METHODS: This retrospective study enrolled consecutive patients with low ovarian reserve who underwent IVF/intracytoplasmic sperm injection (ICSI) at Guangdong Second Provincial General Hospital between January 2017 and April 2021. The primary outcome for pregnancy rate of 478 natural cycles and 448 mild stimulated cycles was compared. Secondary outcomes included embryo quality and oocyte retrieval time of natural cycles. RESULTS: The pregnancy rate in the natural cycle group was significantly higher than that in the mildly stimulated cycle group (51.8% vs. 40.1%, p = 0.046). Moreover, natural cycles exhibited higher rates of available embryos (84.1% vs. 78.6%, p = 0.040), high-quality embryos (61.8% vs. 53.2%, p = 0.008), and utilisation of oocytes (73% vs. 65%, p = 0.001) compared to mildly stimulated cycles. Oocyte retrievals in natural cycles were predominantly performed between 7:00 and 19:00, with 94.9% occurring during this time frame. In natural cycles with high-quality embryos, 96.4% of oocyte retrievals were also conducted between 7:00 and 19:00. CONCLUSION: Natural cycles with appropriately timed oocyte retrieval may present a valuable option for patients with low ovarian reserve.

In the realm of in-vitro fertilisation (IVF) treatment, women with low ovarian reserve often face the crucial decision of opting for natural or mildly stimulated cycles. This retrospective study, conducted between January 2017 and April 2021 at Guangdong Second Provincial General Hospital, delves into the impact of these cycles on pregnancy outcomes. Examining 478 natural cycles and 448 mildly stimulated cycles, the study reveals a notably higher pregnancy rate in the natural cycle group (51.8% vs. 40.1%). Additionally, natural cycles demonstrated higher rates of available embryos, high-quality embryos, and oocyte utilisation compared to their mildly stimulated counterparts. The findings suggest that natural cycles, with proper oocyte retrieval timing, could be a favourable choice for those with low ovarian reserve seeking IVF treatment.

Continuous light exposure influences luteinization and luteal function of ovary in ICR mice.

With the rapid change of people's lifestyle, more childbearing couples live with irregular schedules (i.e., staying up late) and suffer from decreased fertility and abortion, which can be caused by luteal phase defect (LPD). We used continuous light-exposed mice as a model to observe whether continuous light exposure may affect luteinization and luteal function. We showed that the level of progesterone in serum reduced (p < .001), the number of corpus luteum (CL) decreased (p < .01), and the expressions of luteinization-related genes (Lhcgr, Star, Ptgfr, and Runx2), clock genes (Clock and Per1), and Mt1 were downregulated (p < .05) in the ovaries of mice exposed to continuous light, suggesting that continuous light exposure induces defects in luteinization and luteal functions. Strikingly, injection of melatonin (3 mg/kg) could improve luteal functions in continuous light-exposed mice. Moreover, we found that, after 2 h of hCG injection, the level of pERK1/2 in the ovary decreased in the continuous light group, but increased in the melatonin administration group, suggesting that melatonin can improve LPD caused by continuous light exposure through activating the ERK1/2 pathway. In summary, our data demonstrate that continuous light exposure affects ovary luteinization and luteal function, which can be rescued by melatonin.

Application of the modified cytosine base-editing in the cultured cells of bama minipig.

Bama minipig is a unique miniature swine bred from China. Their favorable characteristics include delicious meat, strong adaptability, tolerance to rough feed, and high levels of stress tolerance. Unfavorable characteristics are their low lean meat percentage, high fat content, slow growth rate, and low feed conversion ratio. Genome-editing technology using CRISPR/Cas9 efficiently knocked out the myostatin gene (MSTN) that has a negative regulatory effect on muscle production, effectively promoting pig muscle growth and increasing lean meat percentage of the pigs. However, CRISPR/Cas9 genome editing technology is based on random mutations implemented by DNA double-strand breaks, which may trigger genomic off-target effects and chromosomal rearrangements. The application of CRISPR/Cas9 to improve economic traits in pigs has raised biosafety concerns. Base editor (BE) developed based on CRISPR/Cas9 such as cytosine base editor (CBE) effectively achieve targeted modification of a single base without relying on DNA double-strand breaks. Hence, the method has greater safety in the genetic improvement of pigs. The aim of the present study is to utilize a modified CBE to generate MSTN-knockout cells of Bama minipigs. Our results showed that the constructed "all-in-one"-modified CBE plasmid achieved directional conversion of a single C·G base pair to a T·A base pair of the MSTN target in Bama miniature pig fibroblast cells. We successfully constructed multiple single-cell colonies of Bama minipigs fibroblast cells carrying the MSTN premature termination and verified that there were no genomic off-target effects detected. This study provides a foundation for further application of somatic cell cloning to construct MSTN-edited Bama minipigs that carry only a single-base mutation and avoids biosafety risks to a large extent, thereby providing experience and a reference for the base editing of other genetic loci in Bama minipigs.

Prevalence of Frailty in Older Men and Women: Cross-Sectional Data from the Geelong Osteoporosis Study.

Few studies have investigated the prevalence of frailty in the Australian general population. This study determined the prevalence of frailty in a population-based sample of older adults and examined the relationship between frailty and comorbid conditions. Men (n = 347) and women (n = 360) aged ≥ 60 year from the Geelong Osteoporosis Study (GOS) were assessed between 2016-2019 and 2011-2014, respectively. Frailty was identified using a modified Fried frailty phenotype. Prevalence estimates were standardised to the 2011 Australian population. Kruskal-Wallis test and χ2 test were used to analyse data. For women, mean standardised prevalence estimates were 18.3% (14.1-22.5) for frail, 54.1% (47.3-60.8) pre-frail and 22.9% (18.9-26.8) robust. Corresponding estimates for men were 13.1% (9.8-16.3) frail, 47.8% (42.0-53.6) pre-frail and 27.3% (22.7-31.8) robust. Women who were frail were older, shorter, tended to have a higher body mass index (BMI) and used more medications compared to other groups. Compared to robust women, those who were frail were more likely to have cardio-metabolic (OR 3.5 (0.7-20.0)), pulmonary (OR 3.5 (1.5-8.4)) and musculoskeletal (OR 10.1 (2.1-48.0)) conditions. Frail men were older, had a higher BMI and were more likely to have musculoskeletal conditions (OR 5.8 (2.8-12.3)) and tended to be from a lower SES. No further associations were observed. This study reported the prevalence of frail and pre-frail individuals in a population-based sample of Australian men and women. Frailty was associated with musculoskeletal conditions for both men and women; however, associations with cardio-metabolic and pulmonary comorbidities were evident in women only.

An LRR-only protein regulates abscisic acid-mediated abiotic stress responses during Arabidopsis seed germination.

KEY MESSAGE: LRRop-1, induced by DOF6 transcription factor, negatively regulates abiotic stress responses during Arabidopsis seed germination. The lrrop-1 mutant has reduced ABA signaling, which is part of the underlying stress-remediation mechanism. The large family of leucine-rich repeat (LRR) proteins plays a role in plant immune responses. Most LRR proteins have multiple functional domains, but a subfamily is known to possess only the LRR domain. The roles of these LRR-only proteins in Arabidopsis remain largely uncharacterized. In the present study, we have identified 44 LRR-only proteins in Arabidopsis and phylogenetically classified them into nine sub-groups. We characterized the function of LRRop-1, belonging to sub-group V. LRRop-1 encodes a predominantly ER-localized LRR domain-containing protein that is highly expressed in seeds and rosette leaves. Promoter motif analysis revealed an enrichment in binding sites for several GA-responsive and stress-responsive transcription factors. The lrrop-1 mutant seeds showed enhanced seed germination on medium containing abscisic acid (ABA), paclobutrazol and NaCl compared to the wild type (WT), demonstrating higher abiotic stress tolerance. Also, the lrrop-1 mutant seeds have lower levels of endogenous ABA, but higher levels of gibberellic acid (GA) and jasmonic acid-Ile (JA-Ile) compared to the WT. Furthermore, lrrop-1 mutant seeds imbibed with ABA exhibited reduced expression of ABA-responsive genes compared to similarly treated WT seeds, suggesting suppressed ABA signaling events in the mutant. Furthermore, chromatin immunoprecipitation (ChIP) data showed that DNA BINDING1 ZINC FINGER6 (DOF6), a negative regulator of seed germination, could directly bind to the LRRop-1 promoter and up-regulate its expression. Thus, our results show that LRRop-1 regulates ABA-mediated abiotic stress responses during Arabidopsis seed germination.

Allergen immunotherapy improves defective follicular regulatory T cells in patients with allergic rhinitis.

BACKGROUND: The function of follicular regulatory T (TFR) cells, especially in regulating IgE production in patients with allergic diseases, is poorly understood. OBJECTIVE: We sought to investigate the phenotype, function, and clinical relevance of TFR cells in patients with allergic rhinitis (AR). METHODS: The phenotype and frequency of tonsillar and circulating TFR cells were characterized by using flow cytometry. TFR cell function was examined in an assay by coculturing with follicular helper T cells and B cells. The associations between TFR cells and the clinical features in patients with AR before and after allergen immunotherapy (AIT) were analyzed. RESULTS: TFR cells were detected in germinal centers of tonsils, but compared with subjects without AR, the frequencies decreased in patients with AR who were allergic to house dust mites. Circulating TFR cells in blood were phenotypically and numerically correlated with tonsillar TFR cells, and a reduction of circulating TFR cells but not total or CXCR5- regulatory T cells was noted in patients with AR compared with healthy control subjects. Moreover, circulating TFR cells in patients with AR showed a specific defect in suppressing IgE production but were capable of suppressing production of other immunoglobulin types. We identified negative associations of circulating TFR cell frequencies and function with antigen-specific IgE levels or disease severity in patients with AR. After AIT, the frequencies and function of circulating TFR cells were improved, which positively associated with disease remission. CONCLUSION: Impairment in TFR cells might contribute to aberrant IgE production in patients with AR, and AIT improves defective TFR cell function. TFR cells might serve as a potential biomarker to monitor clinical response to AIT.

Carbohydrate-based vaccines for oncotherapy.

Cancer is still one of the most serious threats to human worldwide. Aberrant patterns of glycosylation on the surface of cancer cells, which are correlated with various cancer development stages, can differentiate the abnormal tissues from the healthy ones. Therefore, tumor-associated carbohydrate antigens (TACAs) represent the desired targets for cancer immunotherapy. However, these carbohydrate antigens may not able to evoke powerful immune response to combat with cancer for their poor immunogenicity and immunotolerance. Different approaches have been developed to address these problems. In this review, we want to summarize the latest advances in TACAs based anticancer vaccines.

High plasma interleukin-6 levels associated with poor prognosis of patients with advanced hepatocellular carcinoma.

PURPOSE: Antiangiogenic therapy is crucial for advanced hepatocellular carcinoma (HCC) treatment. Interleukin (IL)-6 is an inflammatory response mediator that can promote angiogenesis. We explored its prognostic role in patients with advanced HCC. METHODS: We had two patient cohorts, both comprising patients who received sorafenib-containing therapy as the first-line treatment for advanced HCC. We explored the best cut point for pretreatment plasma IL-6 levels in the exploration cohort and then confirmed it in the validation cohort. RESULTS: In total, 55 and 73 patients constituted the exploration and validation cohorts, respectively. In the exploration cohort, a cut point of 4.28 pg/ml was the best for defining high and low IL-6 levels because it could most effectively differentiate overall survival (OS). On application of this cut point to the validation cohort, patients with high plasma IL-6 levels, compared with patients with low IL-6 levels, exhibited significantly poorer OS (median, 8.0 vs 13.9 months, P = 0.031) but similar progression-free survival or treatment response. After adjusting for patient demographics and tumor characteristics, a high plasma IL-6 level remained an independent predictor of poor OS (hazard ratio 2.594, P = 0.005). CONCLUSION: High pretreatment plasma IL-6 levels were associated with poor prognosis of patients with advanced HCC.

Hippocampal Src kinase is required for novelty-induced enhancement of contextual fear extinction.

Exposure to a novel environment enhances the extinction of contextual fear through the "tagging-and-capture" process. However, the underlying molecular mechanisms of novelty-induced enhancement of fear extinction are still unclear. NMDA receptor activity was recently revealed to be required for the enhancement of fear extinction caused by exposure to novelty. Src family kinases (SFKs) act as a molecular hub for regulation of NMDA receptors. We hypothesized that SFKs might be involved in novelty-induced enhancement of fear extinction. We found that the enhancement of fear extinction induced by novelty exposure is accompanied by Src kinase phosphorylation and activation in a restricted time window. Furthermore, intrahippocampal infusion of SFKs inhibitor PP2 inhibits Src kinase phosphorylation and activation, attenuates the activation of NR2B-containing NMDA receptors, and thereby reverses the enhancement of fear extinction induced by novelty exposure. These results suggested that Src kinase may serve as a behavioral tag in the procedural enhancement of fear extinction by novelty exposure.

RFX-1-dependent activation of SHP-1 inhibits STAT3 signaling in hepatocellular carcinoma cells.

Regulatory factor X-1 (RFX-1) is a transcription factor that has been linked to negative regulation of tumor progression; however, its biological function and signaling cascades are unknown. Here, we performed several studies to elucidate the roles of RFX-1 in the regulation of SHP-1 in hepatocellular carcinoma (HCC) cells. Overexpression of RFX-1 resulted in the activation of SHP-1 and repressed colony formation of HCC cells. In addition, by a mouse xenograft model, we demonstrated that RFX-1 overexpression also inhibited the tumor growth of HCC cells in vivo, suggesting that RFX-1 is of potential interest for small-molecule-targeted therapy. We also found that SC-2001, a bipyrrole molecule, induced apoptosis in HCC cells through activating RFX-1 expression. SC-2001 induced RFX-1 translocation from the cytosol to nucleus, bound to the SHP-1 promoter, and activated SHP-1 transcription. In a xenograft model, knockdown of RFX-1 reversed the antitumor effect of SC-2001. Notably, SC-2001 is much more potent than sorafenib, a clinically approved drug for HCC, in in vitro and in vivo assays. Our study confirmed that RFX-1 acts as a tumor suppressor in HCC and might be a new target for HCC therapy. The findings of this study also provide a new lead compound for targeted therapy via the activation of the RFX-1/SHP-1 pathway.

Nintedanib (BIBF-1120) inhibits hepatocellular carcinoma growth independent of angiokinase activity.

BACKGROUND & AIMS: Nintedanib, a triple angiokinase inhibitor, is currently being evaluated against advanced HCC in phase I/II clinical trials. Here, we report the underlying molecular mechanism by which nintedanib (BIBF-1120) induces an anti-HCC effect. METHODS: To further elucidate whether the effect of nintedanib on SHP-1 is dependent on its angiokinase inhibition activity, we developed a novel kinase-independent derivative of nintedanib, ΔN. HCC cell lines were treated with nintedanib or its derivative (ΔN) and apoptosis, signal transduction, and phosphatase activity were analyzed. Purified SHP-1 proteins or HCC cells expressing deletion N-SH2 domain or D61A point mutants were used to investigate the potential effect of nintedanib on SHP-1. In vivo efficacy was determined in nude mice with HCC subcutaneous xenografts (n⩾8 mice). RESULTS: Nintedanib induced anti-proliferation in HCC cell lines by targeting STAT3. Ectopic STAT3 abolished nintedanib-mediated apoptosis in HCC cells. Nintedanib further activated SHP-1 in purified SHP-1 proteins suggesting that nintedanib directly affects SHP-1 for STAT3 inhibition. HCC cells or recombinant SHP-1 proteins expressing deletion of N-SH2 domain or D61A mutants restored the activity of nintedanib suggesting that the auto-inhibition structure of SHP-1 was relieved by nintedanib. Although ΔN only retained the backbone of nintedanib without kinase activity, ΔN still induced substantial anti-HCC activity in vitro and in vivo by targeting STAT3. CONCLUSIONS: Nintedanib induced significant anti-HCC activity independent of angiokinase inhibition activity in a preclinical HCC model by relieving autoinhibition of SHP-1. Our findings provide new mechanistic insight into the inhibition of HCC growth by nintedanib.

The effect and mechanism of palmar ginseng in type 2 diabetic cognitive impairment.

Objective: To investigate the therapeutic effect of palmar ginseng on cognitive impairment in rats with type 2 diabetes, evaluate its neuroprotective effects, and explore its underlying mechanism. Methods: A rat model of diabetic cognitive impairment (DCI) was established by feeding with homemade high-fat, high-sugar chow combined with intraperitoneal injection of streptozotocin (STZ). Rats were continually fed high-fat, high-sugar chow for 60 days after successful induction of the model. Palmar ginseng was administered via gavage. The Morris test was performed after 30 days of treatment. At the end of the test, blood samples were collected, and the activities of IL-6, IL-10, TNF-α, and IL-1ß in rat serum. Pathological changes in hippocampal tissues were observed by Haematoxylin-eosin (HE) staining of the brain, activation of microglia in hippocampal tissues was detected by immunofluorescence, and the expression of PI3K/Akt/mTOR and JAK2/STAT3 proteins in the hippocampal tissues by Western blot. Results: During the administration of palmar Ginseng, the body weight and blood glucose levels of DCI rats were measured weekly, with results showing that Palmar Ginseng effectively reduced blood glucose levels and body weight of DCI rats. Behavioural tests in the water maze indicated that palmar ginseng effectively improved the learning and memory ability of DCI rats. HE and immunofluorescence staining showed that palmar ginseng improved DCI in rats, ameliorated hippocampal neuronal damage, and improved microglial activation. ELISA showed that palmar ginseng significantly reduced the expression of pro-inflammatory factors in the serum of DCI rats. Increased expression of anti-inflammatory factors was observed, and Western blot analysis showed that Palmar Ginseng regulated PI3K/Akt/mTOR and JAK2/STAT3 protein expression, promoted the phosphorylation of PI3K/Akt/mTOR, and inhibited JAK2/STAT3 protein phosphorylation in rat hippocampal tissues as well as in BV2 cells. Conclusions: Palmar ginseng may improve the onset and development of DCI by upregulating the phosphorylation of proteins in the PI3K/Akt/mTOR pathway.

Genetic variation and evolutionary characteristics of Echovirus 11: new variant within genotype D5 associated with neonatal death found in China.

Echovirus 11 (E11) has gained attention owing to its association with severe neonatal infections. From 2018 to 2023, a surge in severe neonatal cases and fatalities linked to a novel variant of genotype D5 was documented in China, France, and Italy. However, the prevention and control of E11 variants have been hampered by limited background data on the virus circulation and genetic variance. Therefore, the present study investigated the circulating dynamics of E11 and the genetic variation and molecular evolution of genotype D5 through the collection of strains from the national acute flaccid paralysis (AFP) and hand, foot, and mouth disease (HFMD) surveillance system in China during 2000-2022 and genetic sequences published in the GenBank database. The results of this study revealed a prevalent dynamic of E11 circulation, with D5 being the predominant genotype worldwide. Further phylogenetic analysis of genotype D5 indicated that it could be subdivided into three important geographic clusters (D5-CHN1: 2014-2019, D5-CHN2: 2016-2022, and D5-EUR: 2022-2023). Additionally, variant-specific (144) amino acid mutation sites and positive-selection pressure sites (132, 262) were identified in the VP1 region. Cluster-specific recombination patterns were also identified, with CVB5, E6, and CVB4 as the major recombinant viruses. These findings provide a preliminary landscape of E11 circulation worldwide and basic scientific data for further study of the pathogenicity of E11 variants.

Flat Chern band in a two-dimensional organometallic framework.

By combining exotic band dispersion with nontrivial band topology, an interesting type of band structure, namely, the flat Chern band, has recently been proposed to spawn high-temperature fractional quantum Hall states. Despite the proposal of several theoretical lattice models, however, it remains doubtful whether such a "romance of flatland" could exist in a real material. Here, we present a first-principles design of a two-dimensional indium-phenylene organometallic framework that realizes a nearly flat Chern band right around the Fermi level by combining lattice geometry, spin-orbit coupling, and ferromagnetism. An effective four-band model is constructed to reproduce the first-principles results. Our design, in addition, provides a general strategy to synthesize topologically nontrivial materials by virtue of organic chemistry and nanotechnology.

Identification of Pla a 7 as a novel pollen allergen group in Platanus acerifolia pollen.

BACKGROUND: Platanus acerifolia is recognized as a source of allergenic pollen worldwide. Currently, five Platanus acerifolia pollen allergens belonging to different protein families have been identified, in which profilin and enolase were characterized by our group recently. Besides, we also screened and identified a novel allergen candidate as triosephosphate isomerase, which was different from already known types of pollen allergens. However, the role of this novel allergen group in Platanus acerifolia pollen allergy was unclear. Therefore, we further investigated the allergenicity and clarify its clinical relevance in this study. METHODS: The natural triosephosphate isomerase from Platanus acerifolia pollen was purified by three steps of chromatography and identified by mass spectrometry. The cDNA sequence of this protein was matched from in-house transcripts based on internal peptide sequences, which was further confirmed by PCR cloning. The recombinant triosephosphate isomerase was expressed and purified from E. coli. Allergenicity analysis of this protein was carried out by enzyme linked immunosorbent assay, immunoblot, and basophil activation test. RESULTS: A novel allergen group belonging to triosephosphate isomerase was firstly identified in Platanus acerifolia pollen and named as Pla a 7. The cDNA of Pla a 7 contained an open reading frame of 762 bp encoding 253 amino acids. The natural Pla a 7 displayed 41.4% IgE reactivity with the patients' sera by ELISA, in which the absorbance value showed correlation to the serum sIgE against Platanus acerifolia pollen extract. Inhibition of IgE-binding to pollen extracts reached 26%-94% in different Pla a 7-positive sera. The recombinant Pla a 7 exhibited weaker IgE-reactivity in ELISA than its natural form, but showed comparable activity in immunoblot. The allergenicity was further confirmed by basophil activation test. CONCLUSIONS: Triosephosphate isomerase (Pla a 7) was first recognized as pollen allergen in Platanus acerifolia pollen, which is a completely different type of pollen allergen from those previously reported. This finding is essential to enrich information on allergen components and pave the way for molecular diagnosis or treatment strategies for Platanus acerifolia pollen allergy.

Identification and characterization of natural PR-1 protein as major allergen from Humulus japonicus pollen.

BACKGROUND: The Humulus japonicus pollen is one of the most common allergenic pollens in China. However, little is unveiled regarding the allergenic components in Humulus japonicus pollen. Our study aimed to purify and identify the pathogenesis-related 1 (PR-1) protein from Humulus japonicus pollen, and to characterize the molecular and immunochemical properties of this novel allergen. METHODS: The natural PR-1 protein (named as Hum j PR-1) was purified from Humulus japonicus pollen extracts with a combined strategy of chromatography, and identified by mass spectrometry. The coding sequence of Hum j PR-1 was confirmed by cDNA cloning. The recombinant Hum j PR-1 was expressed and purified from Escherichia coli. The allergenicity was assessed by immunoblot, enzyme-linked immunosorbent assay (ELISA), inhibition ELISA, and basophil activation test using Humulus japonicus allergic patients' whole blood. The physicochemical properties and 3-dimensional structure of it were comprehensively characterized by in silico methods. RESULTS: The allergenicity analysis revealed that 76.6 % (23/30) of the Humulus japonicus pollen allergic patients displayed specific IgE recognition of the natural Hum j PR-1. The cDNA sequence of Hum j PR-1 had a 516-bp open reading frame encoding 171 amino acids. Physicochemical analysis indicated that Hum j PR-1 was a stable and relatively thermostable protein. Hum j PR-1 shared a similar 3-dimensional folding pattern with other homologous allergens, which was a unique αßα sandwich structure containing 4 α-helices and 6 antiparallel ß-sheets, encompassing 4 conserved CAP domain. CONCLUSION: The natural PR-1 was firstly purified and characterized as a major allergenic allergen in Humulus japonicus pollen. These findings would contribute to developing diagnostic and therapeutic strategies for Humulus japonicus pollinosis.