PP2A B55α Inhibits Epithelial-Mesenchymal Transition Via Regulation of Slug Expression in Non-Small Cell Lung Cancer.

PP2A B55α, encoded by PPP2R2A, acts as a regulatory subunit of the serine/threonine phosphatase PP2A. Despite a frequent loss of heterozygosity of PPP2R2A in cases of non-small cell lung cancer (NSCLC), research on PP2A B55α's functions remains limited and controversial. To investigate the biological roles of PP2A B55α, we conducted bulk RNA-sequencing to assess the impact of PPP2R2A knockdown using two shRNAs in a NSCLC cell line. Gene set enrichment analysis (GSEA) of the RNA-sequencing data revealed significant enrichment of the epithelial-mesenchymal transition (EMT) pathway, with SNAI2 (the gene encoding Slug) emerging as one of the top candidates. Our findings demonstrate that PP2A B55α suppresses EMT, as PPP2R2A deficiency through knockdown or homozygous or hemizygous depletion promotes EMT and metastatic behavior in NSCLC cells, as evidenced by changes in EMT biomarkers, invasion and migration abilities, as well as metastasis in a tail vein assay. Mechanistically, PP2A B55α inhibits EMT by downregulating SNAI2 expression via the GSK3ß-ß-catenin pathway. Importantly, PPP2R2A deficiency also slows cell proliferation by disrupting DNA replication, particularly in PPP2R2A-/- cells. Furthermore, PPP2R2A deficiency, especially PPP2R2A-/- cells, leads to an increase in the cancer stem cell population, which correlates with enhanced resistance to chemotherapy. Overall, the decrease in PP2A B55α levels due to hemizygous/homozygous depletion heightens EMT and the metastatic or stemness/drug resistance potential of NSCLC cells despite their proliferation disadvantage. Our study highlights the significance of PP2A B55α in EMT and metastasis and suggests that targeting EMT/stemness could be a potential therapeutic strategy for treating PPP2R2A-deficient NSCLC.

Bioorthogonal Labeling and Enrichment of Histone Monoaminylation Reveal Its Accumulation and Regulatory Function in Cancer Cell Chromatin.

Histone monoaminylation (i.e., serotonylation and dopaminylation) is an emerging category of epigenetic mark occurring on the fifth glutamine (Q5) residue of H3 N-terminal tail, which plays significant roles in gene transcription. Current analysis of histone monoaminylation is mainly based on site-specific antibodies and mass spectrometry, which either lacks high resolution or is time-consuming. In this study, we report the development of chemical probes for bioorthogonal labeling and enrichment of histone serotonylation and dopaminylation. These probes were successfully applied for the monoaminylation analysis of in vitro biochemical assays, cells, and tissue samples. The enrichment of monoaminylated histones by the probes further confirmed the crosstalk between H3Q5 monoaminylation and H3K4 methylation. Finally, combining the ex vivo and in vitro analyses based on the developed probes, we have shown that both histone serotonylation and dopaminylation are highly enriched in tumor tissues that overexpress transglutaminase 2 (TGM2) and regulate the three-dimensional architecture of cellular chromatin.

[Sensitivity of colorectal cancer organoids to hyperthermic intraperitoneal chemotherapy with lobaplatin].

Objective: To investigate the sensitivity of tumor organoids derived from samples of colorectal cancer to lobaplatin and oxaliplatin hyperthermic perfusion in vitro and to assist clinical development of hyperthermic intraperitoneal chemotherapy. Method: Tumor samples and relevant clinical data were collected from patients with pathologically confirmed colorectal cancer in the Sixth Affiliated Hospital of Sun Yat-sen University from July 2021 to December 2022. Organoids were cultured and tumor tissue were passaged. In vitro hyperthermic perfusion experiments were performed on organoids with good viability. Firstly, 10 organoids were treated with oxaliplatin and lobaplatin at the following six concentrations: 1 000, 250, 62.5, 15.6, 3.9, and 0.98 µmol/L. The organoids were exposed to oxaliplatin at 42℃ for 30 minutes and to lobaplatin at 42℃ for 60 minutes. Dose-response curves of responses to in vitro hyperthermic perfusion with these two drugs were constructed and evaluated. Clinical doses of oxaliplatin and lobaplatin were further tested on 30 organoids. This testing revealed oxaliplatin was effective at 579 µmol/L at a hyperthermic perfusion temperature of 42℃ for 30 min and lobaplatin was effective at 240 µmol/L at a hyperthermic perfusion temperature of 42℃ for 60 minutes. Result: Thirty-two tumor organoids were cultured from samples of colorectal cancer. The median concentration required for oxaliplatin to eliminate 50% of tumor cells (IC50) was 577.45 µmol/L (IQR: 1846.09 µmol/L). The median IC50 for lobaplatin was 85.04 µmol/L (IQR: 305.01 µmol/L).The difference between the two groups was not statistically significant (Z=1.784, P=0.084). In seven of 10 organoids, lobaplatin showed a greater IC50 after in vitro hyperthermic perfusion than did oxaliplatin. Testing of 30 organoids with clinical doses of oxaliplatin and lobaplatin revealed that oxaliplatin achieved an average inhibition rate of 39.6% (95%CI: 32.1%‒47.0%), whereas the average rate of inhibition for lobaplatin was 89.7% (95%CI: 87.0%‒92.3%): this difference is statistically significant (t=‒15.282, P<0.001). Conclusion: The rate of inhibition achieved by hyperthermic perfusion of lobaplatin in vitro is better than that achieved by hyperthermic perfusion with oxaliplatin. Lobaplatin is more effective than oxaliplatin when administered by hyperthermic intraperitoneal perfusion and therefore has the potential to replace oxaliplatin in this setting.

Bioorthogonal labeling and enrichment of histone monoaminylation reveal its accumulation and regulatory function in cancer cell chromatin.

Histone monoaminylation ( i . e ., serotonylation and dopaminylation) is an emerging category of epigenetic mark occurring on the fifth glutamine (Q5) residue of H3 N-terminal tail, which plays significant roles in gene transcription. Current analysis of histone monoaminylation is mainly based on site-specific antibodies and mass spectrometry, which either lacks high resolution or is time-consuming. In this study, we report the development of chemical probes for bioorthogonal labeling and enrichment of histone serotonylation and dopaminylation. These probes were successfully applied for the monoaminylation analysis of in vitro biochemical assays, cells, and tissue samples. The enrichment of monoaminylated histones by the probes further confirmed the crosstalk between H3Q5 monoaminylation and H3K4 methylation. Finally, combining the ex vivo and in vitro analyses based on the developed probes, we have shown that both histone serotonylation and dopaminylation are highly enriched in tumor tissues that overexpress transglutaminase 2 (TGM2) and regulate the three-dimensional architecture of cellular chromatin.

[Application of modified urethral separation method in artificial urethral sphincter implantation and its influence on intraoperative urethral pressure profilometry].

Objective: To explore the application of modified urethral separation method in artificial urethral sphincter (AUS) implantation in patients with stress urinary incontinence (SUI), and its influence on the results of urethral pressure profilometry. Methods: A prospective collection of clinical data was conducted on 25 patients with stress urinary incontinence who underwent modified urethral separation method in AUS implantation and underwent urethral pressure profilometry in Beijing Hospital, Beijing Jishuitan Hospital Affiliated to Capital Medical University and the Second Hospital Affiliated to Tianjin Medical University from March 2019 to June 2023. The improved urethral separation method was to borrow part of the white membrane tissue of the cavernous body while freeing the dorsal side of the cavernous body of the urethra. The circumference of the urethra, sleeve size, and urethral pressure were recorded, the patient's autonomous urinary control before and after surgery and the changes of the international consultation on incontinence questionnaire-short form (ICI-Q-SF) score, incontinence quality of life questionnaire (I-QoL) score, urinary frequency score, nocturia score were compared. Follow-up was conducted in the clinic or by telephone at 1, 3, 6, and 12 months after activation of the device, and once a year thereafter. Local skin status and urine control were assessed, residual urine volume was measured by ultrasound and subjective score scale was completed. Results: All patients were male, aged 27-85 (65.8±15.7) years old. The circumference of the cuff used in this study was 4.0 cm in 4 patients (16.0%), 4.5 cm in 16 patients (64.0%), 5.0 cm in 4 patients (16.0%), and 5.5 cm in 1 patient (4.0%). Among them, the urethral circumference matched the cuff size in 14 cases (56.0%), the urethral circumference was smaller than the cuff size in 4 cases (16.0%), and the urethral circumference was larger than the cuff size in 7 cases (28.0%). Preoperative urodynamic examination showed that the maximum urethral pressure (MUP) was (78.0±25.9) cmH2O, (1 cmH2O=0.098 kPa) and the maximum urethral closure pressure (MUCP) was (53.4±26.6) cmH2O. The MUP of AUS device in the inactivated state was (88.0±26.5) cmH2O, which was not significantly higher than that before operation (P>0.05). The MUCP was (68.2±24.5) cmH2O, which was significantly higher than that before operation (P<0.05). The MUP and MUCP of the AUS device in the activated state were (146.6±25.2) cmH2O and (123.0±28.3) cmH2O, which were significantly higher than those before surgery and in the inactivated state (both P<0.001). All patients in the group reached the social urinary control standards at the first month of device activation. During a follow-up period of 2-50 months, 22 patients (88.0%) used the initial AUS device and all met social urinary control standards. The AUS device was replaced in 1 case. One patient died of cerebrovascular accident. One patient removed the device due to complications. The number of pads [M (Q1, Q3)] used in 25 patients before and after operation was 4.5 (3.0, 6.5) and 1 (0, 1) respectively, with statistically significant differences (P<0.001). ICI-Q-SF score, I-QoL score, urinary frequency score and nocturia score of 25 patients were significantly improved after surgery (all P<0.05). The incidence of postoperative complications was 20.0% (5/25), including 2 cases of painless hematuria, 1 case of infection, 1 case of urethral erosion, and 1 case of dysuria. Except for one patient who experienced urethral erosion and had his sleeve removed, the remaining four patients regained social urination control with active support treatment, and no symptoms recurred until the last follow-up. Conclusion: The modified urethral separation method has no significant effect on urethral pressure in patients with SUI, and can increase the volume of peri-urethral tissue in the cuff, thereby reducing the risk of intraoperative urethral injury and the incidence of postoperative urethral erosion.

[OCT analysis of in-stent neointima over 5 years post-DES implantation].

Objective: To investigate the characteristics of neointimal hyperplasia (NIH) in patients with in-stent restenosis (ISR) over 5 years post-drug-eluting stent (DES) implantation based on optical coherence tomography (OCT). Methods: In this cross-sectional study, patients with DES-ISR who underwent OCT examination at PLA General Hospital between March 2010 and March 2022 were retrospectively included. All patients were divided into≤5 years DES-ISR group and>5 years DES-ISR group according to the time interval after DES implantation. Quantitative and qualitative analyses were conducted on OCT images to compare the clinical data and lesion characteristics of two patient groups. Furthermore, the independent clinical predictive factors of in-stent neoatherosclerosis (ISNA) were analyzed by multivariable logistic regression. Results: A total of 230 DES-ISR patients with 249 lesions were included, with an age of (63.1±10.4) years and 188 males (81.7%). The median interval after DES implantation was 6 (2, 9) years. There were 117 patients (122 ISR lesions) in the≤5 years DES-ISR group, and 113 patients (127 ISR lesions) in the>5 years DES-ISR group. Compared with≤5 years DES-ISR,>5 years DES-ISR showed more heterogeneous patterns (65.4% (83/127) vs. 48.4% (59/122), P=0.007), diffuse patterns (46.5% (59/127) vs. 31.2% (38/122), P=0.013), macrophage accumulations (44.1% (56/127) vs. 31.2% (38/122), P=0.035) in NIH and higher prevalence of ISNA (83.5% (106/127) vs. 72.1% (88/122), P=0.031). According to multivariable logistic regression, the independent predictive factor for ISNA was female (OR=0.44, 95%CI 0.21-0.90, P=0.026). Female (OR=0.48, 95%CI 0.23-0.99, P=0.046) and low-density lipoprotein cholesterol level (OR=1.62, 95%CI 1.01-2.59, P=0.046) were independent predictive factors, respectively, for lipid ISNA. Calcified ISNA was independently associated with time interval of post-DES implantation (OR=1.18, 95%CI 1.07-1.29, P=0.001). Conclusion: DES-ISR patients with a time interval of>5 years after stent implantation have a higher prevalence of ISNA and more complex lesions. Gender, the level of low-density lipoprotein cholesterol, and the time interval post-DES implantation are independently correlated with ISNA, lipid ISNA, and calcified ISNA.

Eravacycline, the first four years: health outcomes and tolerability data for 19 hospitals in 5 U.S. regions from 2018 to 2022.

IMPORTANCE: The rise of multidrug-resistant (MDR) pathogens, especially MDR Gram-negatives, poses a significant challenge to clinicians and public health. These resilient bacteria have rendered many traditional antibiotics ineffective, underscoring the urgency for innovative therapeutic solutions. Eravacycline, a broad-spectrum fluorocycline tetracycline antibiotic approved by the FDA in 2018, emerges as a promising candidate, exhibiting potential against a diverse array of MDR bacteria, including Gram-negative, Gram-positive, anaerobic strains, and Mycobacterium. However, comprehensive data on its real-world application remain scarce. This retrospective cohort study, one of the largest of its kind, delves into the utilization of eravacycline across various infectious conditions in the USA during its initial 4 years post-FDA approval. Through assessing clinical, microbiological, and tolerability outcomes, the research offers pivotal insights into eravacycline's efficacy in addressing the pressing global challenge of MDR bacterial infections.

Utility of multigene panel next-generation sequencing in routine clinical practice for identifying genomic alterations in newly diagnosed metastatic nonsmall cell lung cancer.

BACKGROUND: The standard of care in newly diagnosed metastatic non-small cell lung cancer (NSCLC) is to test for aberrations in three genes for driver mutations - ALK, ROS1 and epidermal growth factor receptor (EGFR) - and also for immunohistochemistry to be performed for programmed death-ligand 1 expression level. Next-generation sequencing (NGS), with or without RNA fusion testing, is increasingly used in standard clinical practice to identify patients with potentially actionable mutations. Stratification of NGS mutation tiers is currently based on the European Society of Medical Oncology Scale for Clinical Actionability of Molecular Targets (ESCAT) Tiers I-V and X. AIM: Our aim was to analyse NSCLC tumour samples for the prevalence of Tiers I-V mutations to establish guidance for current and novel treatments in patients with metastatic disease. METHODS: NGS was performed employing the Oncomine Precision Assay (without RNA fusion testing) that interrogates DNA hotspot variants across 45 genes to screen 210 NSCLC tissue samples obtained across six Sydney hospitals between June 2021 and March 2022. RESULTS: In our cohort, 161 of 210 (77%) had at least one gene mutation identified, with 41 of 210 (20%) having two or more concurrent mutations. Tier I mutations included 42 of 210 (20%) EGFR mutations (EIA) and five of 210 (3%) MET exon 14 skipping mutations (EIB). Non-Tier I variants included 22 of 210 (11%) KRAS G12C hotspot mutations (EIIB), with a further 47 of 210 (22%) having non-G12C KRAS (EX) mutations. NGS testing revealed an additional 15% of cases with Tier II ESCAT mutations in NSCLC. Forty-six percent of patients also demonstrated potential Tier III and IV mutations that are currently under investigation in early-phase clinical trials. CONCLUSIONS: In addition to identifying patients with genomic alterations suitable for clinically proven standard-of-care therapeutic options, the 45-gene NGS panel has significant potential in identifying potentially actionable non-Tier 1 mutations that may become future standard clinical practice in NSCLC.

The Enrichment of miRNA-Targeted mRNAs in Translationally Less Active over More Active Polysomes.

miRNAs moderately inhibit the translation and enhance the degradation of their target mRNAs via cognate binding sites located predominantly in the 3'-untranslated regions (UTR). Paradoxically, miRNA targets are also polysome-associated. We studied the polysome association by the comparative translationally less-active light- and more-active heavy-polysome profiling of a wild type (WT) human cell line and its isogenic mutant (MT) with a disrupted DICER1 gene and, thus, mature miRNA production. As expected, the open reading frame (ORF) length is a major determinant of light- to heavy-polysome mRNA abundance ratios, but is rendered less powerful in WT than in MT cells by miRNA-regulatory activities. We also observed that miRNAs tend to target mRNAs with longer ORFs, and that adjusting the mRNA abundance ratio with the ORF length improves its correlation with the 3'-UTR miRNA-binding-site count. In WT cells, miRNA-targeted mRNAs exhibit higher abundance in light relative to heavy polysomes, i.e., light-polysome enrichment. In MT cells, the DICER1 disruption not only significantly abrogated the light-polysome enrichment, but also narrowed the mRNA abundance ratio value range. Additionally, the abrogation of the enrichment due to the DICER1 gene disruption, i.e., the decreases of the ORF-length-adjusted mRNA abundance ratio from WT to MT cells, exhibits a nearly perfect linear correlation with the 3'-UTR binding-site count. Transcription factors and protein kinases are the top two most enriched mRNA groups. Taken together, the results provide evidence for the light-polysome enrichment of miRNA-targeted mRNAs to reconcile polysome association and moderate translation inhibition, and that ORF length is an important, though currently under-appreciated, transcriptome regulation parameter.

SIX4 Controls Anti-PD-1 Efficacy by Regulating STING Expression.

The cGAS/STING cytosolic DNA-sensing pathway plays a significant role in antitumor immunity. Expression of STING is tightly regulated and commonly reduced or defective in many types of cancer. We have identified SIX4 as a significant regulator of STING expression in colon cancer cells. We showed that knockout of SIX4 decreased STING expression at the mRNA and protein levels while ectopic expression of SIX4 increased STING expression. Depletion of SIX4 led to attenuated STING activation and downstream signaling. Reexpression of SIX4 or ectopic expression of STING in SIX4 knockout cells reversed the effect. Ectopic expression of SIX4 enhanced DMXAA and cGAMP-induced STING activation and downstream signaling. Importantly, decrease of SIX4 expression substantially decreased tumor infiltration of CD8+ T cells and reduced the efficacy of PD-1 antibodies to diminish tumor growth in immune competent mice in vivo. Finally, analysis of The Cancer Genome Atlas colon cancer dataset indicated that tumors with high SIX4 expression were significantly enriched in the Inflammatory Response pathway. SIX4 expression also correlated with expression of multiple IFN-stimulated genes, inflammatory cytokines, and CD8A. Taken together, our results implicate that SIX4 is a principal regulator of STING expression in colon cancer cells, providing an additional mechanism and genetic marker to predict effective immune checkpoint blockade therapy responses. SIGNIFICANCE: Our studies demonstrate that SIX4 is an important regulator of STING expression, providing a genetic marker or a therapeutic target to predict or enhance immune checkpoint blockade therapy responses in colon cancer.

Enhanced capillary pumping using open-channel capillary trees with integrated paper pads.

The search for efficient capillary pumping has led to two main directions for investigation: first, assembly of capillary channels to provide high capillary pressures, and second, imbibition in absorbing fibers or paper pads. In the case of open microfluidics (i.e., channels where the top boundary of the fluid is in contact with air instead of a solid wall), the coupling between capillary channels and paper pads unites the two approaches and provides enhanced capillary pumping. In this work, we investigate the coupling of capillary trees-networks of channels mimicking the branches of a tree-with paper pads placed at the extremities of the channels, mimicking the small capillary networks of leaves. It is shown that high velocities and flow rates (7 mm/s or 13.1 µl/s) for more than 30 s using 50% (v/v) isopropyl alcohol, which has a 3-fold increase in viscosity in comparison to water; 6.5 mm/s or 12.1 µl/s for more than 55 s with pentanol, which has a 3.75-fold increase in viscosity in comparison to water; and >3.5 mm/s or 6.5 µl/s for more than 150 s with nonanol, which has a 11-fold increase in viscosity in comparison to water, can be reached in the root channel, enabling higher sustained flow rates than that of capillary trees alone.

Treatment Outcomes for Carbapenem-Resistant and Cephalosporin-Susceptible Pseudomonas aeruginosa Pneumonia.

BACKGROUND: Carbapenem-resistant (Car-R) Pseudomonas aeruginosa is an urgent threat. These isolates may remain susceptible to traditional noncarbapenem antipseudomonal ß-lactams, but it is unclear if carbapenem resistance impacts the effectiveness of these agents. OBJECTIVE: The purpose of this study was to compare clinical outcomes in Car-R and cephalosporin-susceptible (Ceph-S) P. aeruginosa pneumonia treated with cefepime versus other susceptible agents. METHODS: This retrospective cohort study evaluated patients diagnosed with hospital-acquired or ventilator-associated pneumonia who had a respiratory isolate of Car-R Ceph-S P. aeruginosa. Patients were excluded if they had polymicrobial respiratory cultures, other concomitant infections, empyema, death within 3 days of index culture, or received less than 3 days of susceptible therapy. Patients treated with cefepime were compared to other susceptible therapies. The primary endpoint was 30-day in-hospital mortality. RESULTS: Eighty-seven patients were included: cefepime, n = 61; other susceptible therapies, n = 26. There were no differences in 30-day in-hospital mortality between cefepime and other susceptible therapies (19.6% vs. 19.2%, p value = 0.719). In addition, there were no differences between clinical cure rates (cefepime 65.6% vs. other therapies 72 %, p value = 0.47). In multivariate logistic regression, treatment with cefepime (odds ratio [OR], 0.57; 95% confidence interval [CI], 0.11-2.52) was not independently associated with 30-day in-hospital mortality. CONCLUSION AND RELEVANCE: For the treatment of Car-R Ceph-S P. aeruginosa pneumonia, cefepime showed similar rates of 30-day in-hospital mortality and clinical outcomes when compared to other susceptible therapies. Cefepime may be utilized to conserve novel ß-lactam and ß-lactamase inhibitors.

Clinical Outcomes With Extended Versus Intermittent Infusion of Anti-Pseudomonal Beta-Lactams in Patients With Gram-Negative Bacteremia.

Background: Administration of doses via an extended infusion (EI) is an important strategy to optimize beta-lactams. Available data on the impact of EI on outcomes largely focus on clinical cure or mortality in critically ill patients or those with resistant pathogens. The potential benefits of EI extend beyond these populations and outcomes, and further study is warranted. Methods: This was a retrospective cohort study of adult patients who received cefepime, piperacillin/tazobactam, or meropenem for Gram-negative bacteremia via EI or intermittent infusion. Patients were matched 1:1 based on study drug, sepsis severity, intensive care unit (ICU) status, bacteremia source, and pathogen. Outcomes assessed included time to clinical stabilization, rates of treatment failure, mortality, recurrence, and length of stay (LOS). Results: Two hundred sixty-eight patients were included. Baseline characteristics were similar between groups. Forty-two percent of patients were in the ICU at infection onset and the most common pathogen was Escherichia coli (41%). After adjusting for residual differences between groups, receipt of EI was independently associated with shorter time to clinical stability (adjusted odds ratio, 0.32; 95% confidence interval, .22-.47), time to defervescence, and time to white blood cell count normalization. Furthermore, EI was associated with a lower incidence of treatment failure, decreased recurrence of bacteremia, and shorter LOS. There was no difference in mortality. These findings were consistent regardless of patient location (ICU vs ward), baseline renal function, source of bacteremia, or study drug received. Conclusions: These findings suggest that EI beta-lactams are an important stewardship strategy to improve clinical outcomes in patients with Gram-negative bacteremia.

Berberine improves central memory formation of CD8+ T cells: Implications for design of natural product-based vaccines.

Berberine (BBR) as one of the most effective natural products has been increasingly used to treat various chronic diseases due to its immunosuppressive/tolerogenic activities. However, it is unknown if BBR can be applied without abrogating the efforts of vaccination. Here we show that priming of CD8+ T cells in the presence of BBR lead to improved central memory formation (Tcm) with substantially reduced effector proliferation, primarily orchestrated through activation of AMPK and Stat5. Tcm derived from vaccinated mice fed with BBR were able to adoptively transfer protective immunity to naïve recipients. Vaccination of BBR-fed mice conferred better memory protection against infection without losing immediate effector efficacy, suggesting appreciable benefits from using BBR in vaccination. Thus, our study may help to lay the groundwork for mechanistic understanding of the immunomodulatory effects of natural products and their potential use as adjuvant that allows the design of novel vaccines with more desirable properties.

Broad immunity to SARS-CoV-2 variants of concern mediated by a SARS-CoV-2 receptor-binding domain protein vaccine.

BACKGROUND: The SARS-CoV-2 global pandemic has fuelled the generation of vaccines at an unprecedented pace and scale. However, many challenges remain, including: the emergence of vaccine-resistant mutant viruses, vaccine stability during storage and transport, waning vaccine-induced immunity, and concerns about infrequent adverse events associated with existing vaccines. METHODS: We report on a protein subunit vaccine comprising the receptor-binding domain (RBD) of the ancestral SARS-CoV-2 spike protein, dimerised with an immunoglobulin IgG1 Fc domain. These were tested in conjunction with three different adjuvants: a TLR2 agonist R4-Pam2Cys, an NKT cell agonist glycolipid α-Galactosylceramide, or MF59® squalene oil-in-water adjuvant, using mice, rats and hamsters. We also developed an RBD-human IgG1 Fc vaccine with an RBD sequence of the immuno-evasive beta variant (N501Y, E484K, K417N). These vaccines were also tested as a heterologous third dose booster in mice, following priming with whole spike vaccine. FINDINGS: Each formulation of the RBD-Fc vaccines drove strong neutralising antibody (nAb) responses and provided durable and highly protective immunity against lower and upper airway infection in mouse models of COVID-19. The 'beta variant' RBD vaccine, combined with MF59® adjuvant, induced strong protection in mice against the beta strain as well as the ancestral strain. Furthermore, when used as a heterologous third dose booster, the RBD-Fc vaccines combined with MF59® increased titres of nAb against other variants including alpha, delta, delta+, gamma, lambda, mu, and omicron BA.1, BA.2 and BA.5. INTERPRETATION: These results demonstrated that an RBD-Fc protein subunit/MF59® adjuvanted vaccine can induce high levels of broadly reactive nAbs, including when used as a booster following prior immunisation of mice with whole ancestral-strain spike vaccines. This vaccine platform offers a potential approach to augment some of the currently approved vaccines in the face of emerging variants of concern, and it has now entered a phase I clinical trial. FUNDING: This work was supported by grants from the Medical Research Future Fund (MRFF) (2005846), The Jack Ma Foundation, National Health and Medical Research Council of Australia (NHMRC; 1113293) and Singapore National Medical Research Council (MOH-COVID19RF-003). Individual researchers were supported by an NHMRC Senior Principal Research Fellowship (1117766), NHMRC Investigator Awards (2008913 and 1173871), Australian Research Council Discovery Early Career Research Award (ARC DECRA; DE210100705) and philanthropic awards from IFM investors and the A2 Milk Company.

Spike height improves prediction of future seizure risk.

OBJECTIVE: We evaluated whether interictal epileptiform discharge (IED) rate and morphological characteristics predict seizure risk. METHODS: We evaluated 10 features from automatically detectable IEDs in a stereotyped population with self-limited epilepsy with centrotemporal spikes (SeLECTS). We tested whether the average value or the most extreme values from each feature predicted future seizure risk in cross-sectional and longitudinal models. RESULTS: 10,748 individual centrotemporal IEDs were analyzed from 59 subjects at 81 timepoints. In cross-sectional models, increases in average spike height, spike duration, slow wave rising slope, slow wave falling slope, and the most extreme values of slow wave rising slope each improved prediction of an increased risk of a future seizure compared to a model with age alone (p < 0.05, each). In longitudinal model, spike rising height improved prediction of future seizure risk compared to a model with age alone (p = 0.04) CONCLUSIONS: Spike height improves prediction of future seizure risk in SeLECTS. Several other morphological features may also improve prediction and should be explored in larger studies. SIGNIFICANCE: Discovery of a relationship between novel IED features and seizure risk may improve clinical prognostication, visual and automated IED detection strategies, and provide insights into the underlying neuronal mechanisms that contribute to IED pathology.

Molecular Detection of Candidatus Orientia chuto in Wildlife, Saudi Arabia.

Scrub typhus is a zoonosis caused by 3 species of Orientia bacteria, including Candidatus Orientia chuto. This species is known only from a human case in Dubai and infections in wildlife in Kenya. We report molecular detection of Candidatus O. chuto in 2 wild rodent species from Saudi Arabia.

Berberine improves central memory formation of CD8+ T cells: Implications for design of natural product-based vaccines

Berberine (BBR) as one of the most effective natural products has been increasingly used to treat various chronic diseases due to its immunosuppressive/tolerogenic activities. However, it is unknown if BBR can be applied without abrogating the efforts of vaccination. Here we show that priming of CD8+ T cells in the presence of BBR lead to improved central memory formation (Tcm) with substantially reduced effector proliferation, primarily orchestrated through activation of AMPK and Stat5. Tcm derived from vaccinated mice fed with BBR were able to adoptively transfer protective immunity to naïve recipients. Vaccination of BBR-fed mice conferred better memory protection against infection without losing immediate effector efficacy, suggesting appreciable benefits from using BBR in vaccination. Thus, our study may help to lay the groundwork for mechanistic understanding of the immunomodulatory effects of natural products and their potential use as adjuvant that allows the design of novel vaccines with more desirable properties.