Evaluating precision medicine approaches for gene therapy in patient-specific cellular models of Bietti crystalline dystrophy.

Patient-specific induced pluripotent stem cell-derived (iPSC-derived) cell lines allow for therapies to be tailored to individual patients, increasing therapeutic precision and efficiency. Bietti crystalline dystrophy (BCD) is a rare blinding disease estimated to affect about 67,000 individuals worldwide. Here, we used iPSC-derived retinal pigment epithelium (iRPE) cells from patients with BCD to evaluate adeno-associated virus-mediated (AAV-mediated) gene augmentation therapy strategies. We found that BCD iRPE cells were vulnerable to blue light-induced oxidative stress and that cellular phenotype can be quantified using 3 robust biomarkers: reactive oxygen species (ROS), 4-hydroxy 2-nonenal (4-HNE) levels, and cell death rate. Additionally, we demonstrated that AAV-mediated gene therapy can significantly reduce light-induced cell death in BCD iRPE cells. This is the first proof-of-concept study to our knowledge to show that AAV-CYP4V2 gene therapy can be used to treat light-induced RPE damage in BCD. Furthermore, we observed significant variability in cellular phenotypes among iRPE from patients with BCD of divergent mutations, which outlined genotype-phenotype correlations in BCD patient-specific cell disease models. Our results reveal that patient-specific iRPE cells retained personalized responses to AAV-mediated gene therapy. Therefore, this approach can advance BCD therapy and set a precedent for precision medicine in other diseases, emphasizing the necessity for personalization in healthcare to accommodate individual diversity.

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.

Use of a mobile application to monitor drain sites and surgical wounds after discharge from acute care - A feasibility study in Singapore.

PURPOSE: This study aimed to demonstrate the compliance, feasibility, and acceptability of telehealth monitoring among surgical patients discharged with wounds or drains. METHODOLOGY: This is a cross-sectional feasibility study. Post-surgical breast, plastic, and hepatobiliary patients with wounds and/or surgical drains were recruited using convenience sampling. The control group received conventional care which consisted of daily telephone follow-up. The intervention group used a mobile wound application to take wound and drain images, report drainage amount and symptoms. Compliance was assessed by measuring the percentage of actual to expected patient entries, feasibility was assessed by comparing detection of abnormalities and unexpected hospital visits, and acceptability was assessed by subjective feedback from nurses and patients from the intervention group. RESULTS: 59 patients were recruited, with 30 patients in the control group and 29 patients in the intervention group. 9 specialty nurses were involved in the patients' post-discharge care. The mean compliance rate for the hepatobiliary, breast and plastic patients were 89.9 %, 89.5 % and 75.9 % respectively. 4 patients from the intervention group (13.8 %) and 6 patients from the control group (20.1 %) were flagged as having potential abnormalities. As for unexpected hospital visits, there were 2 (6.9 %) in the intervention group and 1 (3.4 %) in the control group. 25 patients and 9 specialty nurses responded to the feedback survey. 22 patients (88 %) did not face any application issues. 18 patients (72 %) preferred to self-report symptoms via the application rather than to call the nurses and reported feeling safe knowing that they are remotely monitored. Most nurses found the app convenient and timesaving (n = 7, 78 %), with monitoring through pictures as more accurate than phone conversation (n = 8, 89 %). CONCLUSION: The results suggest that use of a mobile application by surgical patients discharged with wounds or drains is feasible and serves as a viable monitoring tool.

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.

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.

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.

Effects of Zishui Qinggan Decoction on the hippocampal protein expressions of ERK,GSK3β,CREB and BDNF in a mouse model of depression induced by chronic restraint stress / 中成药

AIM To explore the effects of Zishui Qinggan Decoction on the mouse model of depression induced by chronic restraint stress(CRS)via ERK/GSK3β/CREB/BDNF signaling pathway.METHODS Except for those of the blank group,the mice of other groups were induced into depression models by CRS,and divided into the model group,the fluoxetine hydrochloride group(10 mg/kg)and the low,medium and high dose Zishui Qinggan Decoction groups(8.835,17.670 and 35.340 g/kg)for the corresponding drug intervention and simultanous CRS treatment.The mice had their sugar water preference experiment and behavior experiment on the 7th and 14th day after administration;the observation of the hippocampal morphological changes by HE staining,the detection of the superoxide dismutase(SOD)activity and malondialdehyde(MDA)level in serum by kits,the detection of levels of serum 5-hydroxytryptamine(5-HT),tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β)by ELISA,the detection of the hippocampal mRNA expressions of BDNF,TNF-α and IL-1β by RT-qPCR method,and the detection of the hippocampal protein expressions of ERK1/2,p-ERK1/2,GSK3β,p-GSK3β,CREB and BDNF by Western blot method 14 days after administration.RESULTS Compared with the model group,after 14 days of administration,both fluoxetine hydrochloride group and medium-dose Zishui Qinggan Decoction group displayed increased preference rate of sugar water(P<0.01),shortened immobility time of tail suspension and forced swimming(P<0.01),improved hippocampal damage of nerve cells,decreased levels of serum MDA,TNF-α and IL-1β(P<0.05,P<0.01),increased SOD activity and 5-HT level(P<0.05,P<0.01),decreased hippocampal mRNA expressions of TNF-α and IL-1β(P<0.01),and decreased expressions of BDNF mRNA and p-ERK1/2,p-GSK3β,CREB and BDNF proteins(P<0.05,P<0.01).CONCLUSION Zishui Qinggan Decoction can improve the depression-like behaviors in mice exposed to CRS,and its mechanism may be related to the regulation of hippocampal ERK/GSK3β/CREB/BDNF signaling pathway.

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.

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.

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.

Formulation optimization and analysis of taste-masking effect of licorzine granules based on sensory evaluation and electronic tongue method / 药学学报

Licorzine granules are common preparations for children zinc deficiency. Considering the long course of treatment, the taste of licorzine granules may become a main factor affecting medication adherence. To date there have been no taste evaluation research into licorzine granules yet. In this study, both sensory evaluation and electronic tongue method were utilized to optimize licorzine granules formulations, evaluate the tastes of licorzine, excipients, optimized formulation in vivo and in vitro. As the results show, bitterness and astringency are the main unpleasant tastes generating from licorzine. Xanthan gum is the main taste-masking excipient, lowering down the bitterness and astringency of licorzine by at least one grade. Good correlation exists between the results of sensory evaluation and electronic tongue method, and an integrated combination of the two helps to obtain objective and rational research conclusions. The adult sensory evaluation study was a research-based clinical trial conducted with informed consent from all subjects in accordance with the ethical requirements of Good Clinical Practice.

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.

Improved Neutralization of Omicron BA.4/5, BA.4.6, BA.2.75.2, BQ.1.1, and XBB.1 with Bivalent BA.4/5 Vaccine

The BNT162b2 bivalent BA.4/5 COVID-19 vaccine has been authorized to mitigate COVID-19 due to current Omicron and potentially future variants. New sublineages of SARS-CoV-2 Omicron continue to emerge and have acquired additional mutations, particularly in the spike protein, that may lead to improved viral fitness and immune evasion. The present study characterized neutralization activities against new Omicron sublineages BA.4.6, BA.2.75.2, BQ.1.1, and XBB.1 after a 4th dose (following three doses of BNT162b2) of either the original monovalent BNT162b2 or the bivalent BA.4/5 booster in individuals >55 years of age. For all participants, the 4th dose of monovalent BNT162b2 vaccine induced a 3.0x, 2.9x, 2.3x, 2.1x, 1.8x, and 1.5x geometric mean neutralizing titer fold rise (GMFR) against USA/WA1-2020 (a strain isolated in January 2020), BA.4/5, BA.4.6, BA.2.75.2, BQ.1.1, and XBB.1, respectively; the bivalent vaccine induced 5.8x, 13.0x, 11.1x, 6.7x, 8.7x, and 4.8x GMFRs. For individuals without SARS-CoV-2 infection history, BNT162b2 monovalent induced 4.4x, 3.0x, 2.5x, 2.0x, 1.5x, and 1.3x GMFRs, respectively; the bivalent vaccine induced 9.9x, 26.4x, 22.2x, 8.4x, 12.6x, and 4.7x GMFRs. These data suggest the bivalent BA.4/5 vaccine is more immunogenic than the original BNT162b2 monovalent vaccine against circulating Omicron sublineages, including BQ.1.1 that is becoming prevalent globally.

Cross-neutralization and viral fitness of SARS-CoV-2 Omicron sublineages

The rapid evolution of SARS-CoV-2 Omicron sublineages mandates a better understanding of viral replication and cross-neutralization among these sublineages. Here we used K18-hACE2 mice and primary human airway cultures to examine the viral fitness and antigenic relationship among Omicron sublineages. In both K18-hACE2 mice and human airway cultures, Omicron sublineages exhibited a replication order of BA.5 [≥] BA.2 [≥] BA.2.12.1 > BA.1; no difference in body weight loss was observed among different sublineage-infected mice. The BA.1-, BA.2-, BA.2.12.1-, and BA.5-infected mice developed distinguisable cross-neutralizations against Omicron sublineages, but exhibited little neutralizations against the index virus (i.e., USA-WA1/2020) or the Delta variant. Surprisingly, the BA.5-infected mice developed higher neutralization activity against heterologous BA.2 and BA.2.12.1 than that against homologous BA.5; serum neutralizing titers did not always correlate with viral replication levels in infected animals. Our results revealed a distinct antigenic cartography of Omicron sublineages and support the bivalent vaccine approach.

Low neutralization of SARS-CoV-2 Omicron BA.2.75.2, BQ.1.1, and XBB.1 by 4 doses of parental mRNA vaccine or a BA.5-bivalent booster

The newly emerged SARS-CoV-2 Omicron BQ.1.1, XBB.1, and other sublineages have accumulated additional spike mutations that may affect vaccine effectiveness. Here we report neutralizing activities of three human serum panels collected from individuals 1-3 months after dose 4 of parental mRNA vaccine (post-dose-4), 1 month after a BA.5-bivalent-booster (BA.5-bivalent-booster), or 1 month after a BA.5-bivalent-booster with previous SARS-CoV-2 infection (BA.5-bivalent-booster-infection). Post-dose-4 sera neutralized USA-WA1/2020, BA.5, BF.7, BA.4.6, BA.2.75.2, BQ.1.1, and XBB.1 SARS-CoV-2 with geometric mean titers (GMTs) of 1533, 95, 69, 62, 26, 22, and 15, respectively; BA.5-bivalent-booster sera improved the GMTs to 3620, 298, 305, 183, 98, 73, and 35; BA.5-bivalent-booster-infection sera further increased the GMTs to 5776, 1558,1223, 744, 367, 267, and 103. Thus, although BA.5-bivalent-booster elicits better neutralization than parental vaccine, it does not produce robust neutralization against the newly emerged Omicron BA.2.75.2, BQ.1.1, and XBB.1. Previous infection enhances the magnitude and breadth of BA.5-bivalent-booster-elicited neutralization.

Purification and characterization of enolase as a novel allergen in Platanus acerifolia pollen.

BACKGROUND: The pollen from Platanus acerifolia (P. acerifolia) is one of the main causes of allergic disorders. To date, only 4 allergens have been identified from this pollen. But previous studies showed that there still exist under-recognized allergens in it. The aim of this study was to comprehensively investigate the newly identified enolase (Pla a 6) as a novel allergen in the P. acerifolia pollen. METHODS: The natural (n) Pla a 6 was purified by combined chromatographic strategies. According to the identified internal peptides, the cDNA sequence encoding this allergen was matched from the mRNA-sequencing results of P. acerifolia pollen, which was further amplified and cloned. The recombinant (r) Pla a 6 was expressed and purified from E. coli. The allergenicity of this novel allergen was characterized by enzyme linked immunosorbent assay (ELISA), Western blot, inhibition ELISA, and basophil activation test (BAT). RESULTS: A novel allergen from P. acerifolia pollen, named as Pla a 6 was thoroughly studied, which contained an open reading frame of 1338 bp encoding 445 amino acids. The IgE-binding activity of nPla a 6 was initially proved by Western-blot, and a similar IgE-binding pattern to rPla a 6 was also exhibited. Moreover, the positivity for specific IgE against rPla a 6 was tested as 45.95% (17/37) by ELISA, and IgE binding to pollen extract could be inhibited up to 45.77% by 10 µg/ml of rPla a 6. The protein was also confirmed to activate patients' basophils. CONCLUSIONS: In this study, a novel allergen belonging to enolase family was comprehensively investigated and characterized through its natural and recombinant forms in P. acerifolia pollen. The study will contribute to the development of novel molecular-based diagnostic and therapeutic approaches for P. acerifolia pollen allergy.

Determinants and Mechanisms of the Low Fusogenicity and Endosomal Entry of Omicron Subvariants

The rapid spread and strong immune evasion of the SARS-CoV-2 Omicron subvariants has raised serious concerns for the global COVID-19 pandemic. These new variants exhibit reduced fusogenicity and increased endosomal entry pathway utilization compared to the ancestral D614G variant, the underlying mechanisms of which remain elusive. Here we show that the C-terminal S1 mutations of the BA.1.1 subvariant, H655Y and T547K, critically govern the low fusogenicity of Omicron. Notably, H655Y also dictates the enhanced endosome entry pathway utilization. Mechanistically, T547K and H655Y likely stabilize the spike trimer conformation, as shown by increased molecular interactions in structural modeling as well as reduced S1 shedding. Importantly, the H655Y mutation also determines the low fusogenicity and high dependence on the endosomal entry pathway of other Omicron subvariants, including BA.2, BA.2.12.1, BA.4/5 and BA.2.75. These results uncover mechanisms governing Omicron subvariant entry and provide insights into altered Omicron tissue tropism and pathogenesis.