SARS-CoV-2 spike-based virus-like particles incorporate influenza H1/N1 antigens and induce dual immunity in mice.

A vaccine effective against both SARS-CoV-2 and influenza A (IAV) viruses could represent a cost-effective strategy to reduce their combined public health burden as well as potential complications arising from co-infection. Based on previous findings that full-length SARS-CoV-2 spike (S) expression can induce high-level, enveloped VLP (eVLP) production in CHO cells, we tested whether IAV H1N1 hemagglutinin (H1) and neuraminidase (N1) could also be displayed on these particles. We found that co-incorporation of the IAV surface antigens in spike VLPs (S-VLPs) was highly efficient: upon transient co-expression of S + H1 or S + H1 + N1 in CHO cells, the resulting VLPs contained similar amounts of the SARS-CoV-2 S and IAV antigens. The self-assembled bivalent (S/H1) and trivalent (S/H1/N1) VLPs released into the culture media were purified by single-step chromatography using a S-VLP affinity resin. Western blot analysis and immuno­gold labeling transmission electron microscopy (TEM) of purified VLPs confirmed the coexistence of S, H1 and N1 antigens in the same particles. Finally, we demonstrated that two doses of adjuvanted bivalent and trivalent VLPs elicit specific functional antibodies and cellular immunity in a mouse model, suggesting potential for combined SARS-CoV-2/IAV vaccine development.

Histamine stimulates human microglia to alter cellular prion protein expression via the HRH2 histamine receptor.

Although the cellular prion protein (PrPC) has been evolutionarily conserved, the role of this protein remains elusive. Recent evidence indicates that PrPC may be involved in neuroinflammation and the immune response in the brain, and its expression may be modified via various mechanisms. Histamine is a proinflammatory mediator and neurotransmitter that stimulates numerous cells via interactions with histamine receptors 1-4 (HRH1-4). Since microglia are the innate immune cells of the central nervous system, we hypothesized that histamine-induced stimulation regulates the expression of PrPC in human-derived microglia. The human microglial clone 3 (HMC3) cell line was treated with histamine, and intracellular calcium levels were measured via a calcium flux assay. Cytokine production was monitored by enzyme-linked immunosorbent assay (ELISA). Western blotting and quantitative reverse transcription-polymerase chain reaction were used to determine protein and gene expression of HRH1-4. Flow cytometry and western blotting were used to measure PrPC expression levels. Fluorescence microscopy was used to examine Iba-1 and PrPC localization. HMC3 cells stimulated by histamine exhibited increased intracellular calcium levels and increased release of IL-6 and IL-8, while also modifying PrPC localization. HMC3 stimulated with histamine for 6 and 24 hours exhibited increased surface PrPC expression. Specifically, we found that stimulation of the HRH2 receptor was responsible for changes in surface PrPC. Histamine-induced increases in surface PrPC were attenuated following inhibition of the HRH2 receptor via the HRH2 antagonist ranitidine. These changes were unique to HRH2 activation, as stimulation of HRH1, HRH3, or HRH4 did not alter surface PrPC. Prolonged stimulation of HMC3 decreased PrPC expression following 48 and 72 hours of histamine stimulation. HMC3 cells can be stimulated by histamine to undergo intracellular calcium influx. Surface expression levels of PrPC on HMC3 cells are altered by histamine exposure, primarily mediated by HRH2. While histamine exposure also increases release of IL-6 and IL-8 in these cells, this cytokine release is not fully dependent on PrPC levels, as IL-6 release is only partially reduced and IL-8 release is unchanged under the conditions of HRH2 blockade that prevent PrPC changes. Overall, this suggests that PrPC may play a role in modulating microglial responses.

Inflammation and platelet reactivity during adjunctive colchicine versus aspirin in patients with acute coronary syndrome treated with potent P2Y12 inhibitor.

Background: In patients undergoing percutaneous coronary intervention (PCI), the use of anti-inflammatory therapy with colchicine is associated with a reduction of recurrent ischemic events. The mechanisms of such findings are not fully elucidated. Objectives: To investigate the effects of colchicine versus aspirin on inflammation and platelet reactivity in patients with acute coronary syndrome (ACS) undergoing PCI. Methods: This observational study compared laboratory measurements in ACS patients receiving single antiplatelet therapy with ticagrelor or prasugrel plus colchicine (MACT) (n = 185) versus conventional dual-antiplatelet therapy (DAPT) with aspirin plus ticagrelor or prasugrel (n = 497). The primary outcome was the frequency of high residual inflammation, defined as high-sensitivity C-reactive protein (hs-CRP) ≥2 mg/L at 1 month post-PCI. Multiple sensitivity analyses were performed for the primary outcome, including multivariable adjustment, propensity-score matching, and inverse-probability weighted methods. Results: One month after PCI, patients treated with MACT had significantly lower levels of hs-CRP compared to those treated with DAPT (0.6 [0.4-1.2] vs. 0.9 [0.6-2.3] mg/L, p < 0.001). The frequency of high residual inflammation was also lower in the MACT group (10.8% vs. 27.2%, p < 0.001) (odds ratio [95% confidence interval] = 0.33 [0.20-0.54], p < 0.001). This effect was consistent across sensitivity analyses. There was no difference in platelet reactivity between MACT and DAPT (49.6 ± 49.0 vs. 51.5 ± 66.4 P2Y12 reaction unit [PRU] measured by VerifyNow, p = 0.776). Conclusion: In ACS patients undergoing PCI, MACT was associated with a lower rate of high residual inflammation without increasing platelet reactivity compared to conventional DAPT. Clinical trial registration: NCT04949516 for MACT pilot trial and NCT04650529 for Gyeongsang National University Hospital registry.

Intravascular Imaging and Angiography Guidance in Complex Percutaneous Coronary Intervention Among Patients With Diabetes: A Secondary Analysis of a Randomized Clinical Trial.

Importance: Data are limited regarding the effects of intravascular imaging guidance during complex percutaneous coronary intervention (PCI) in patients with diabetes. Objective: To compare the clinical outcomes of intravascular imaging-guided vs angiography-guided complex PCI in patients with or without diabetes. Design, Setting, and Participants: This prespecified secondary analysis of a subgroup of patients in RENOVATE-COMPLEX-PCI (Randomized Controlled Trial of Intravascular Imaging Guidance Versus Angiography-Guidance on Clinical Outcomes After Complex Percutaneous Coronary Intervention), an investigator-initiated, open-label multicenter trial, analyzed enrolled patients who underwent complex PCI at 20 sites in Korea from May 2018 through May 2021. Eligible patients were randomly assigned in a 2:1 ratio to undergo either the intravascular imaging-guided PCI or angiography-guided PCI. Data analyses were performed from June 2023 to April 2024. Interventions: Percutaneous coronary intervention was performed either under the guidance of intravascular imaging or angiography alone. Main Outcomes and Measures: The primary end point was target vessel failure (TVF), defined as a composite of cardiac death, target vessel-related myocardial infarction, or target vessel revascularization. Results: Among the 1639 patients included in the analysis (mean [SD] age, 65.6 [10.2] years; 1300 males [79.3%]), 617 (37.6%) had diabetes. The incidence of TVF was significantly higher in patients with diabetes than patients without diabetes (hazard ratio [HR], 1.86; 95% CI, 1.33-2.60; P < .001). Among patients without diabetes, the intravascular imaging-guided PCI group had a significantly lower incidence of TVF compared with the angiography-guided PCI group (4.7% vs 12.2%; HR, 0.41 [95% CI, 0.25-0.67]; P < .001). Conversely, in patients with diabetes, the risk of TVF was not significantly different between the 2 groups (12.9% vs 12.3%; HR, 0.97 [95% CI, 0.60-1.57]; P = .90). There was a significant interaction between the use of intravascular imaging and diabetes for the risk of TVF (P for interaction = .02). Among patients with diabetes, only those with good glycemic control (hemoglobin A1c level ≤7.5%) and who achieved stent optimization by intravascular imaging showed a lower risk of future ischemic events (HR, 0.31; 95% CI, 0.12-0.82; P = .02). Conclusions and Relevance: In this secondary analysis of a subgroup of patients in the RENOVATE-COMPLEX-PCI trial, intravascular imaging guidance reduced the risk of TVF compared with angiography guidance in patients without diabetes (but not in patients with diabetes) during complex PCI. In patients with diabetes undergoing complex PCI, attention should be paid to stent optimization using intravascular imaging and glycemic control to improve outcomes. Trial Registration: ClinicalTrials.gov Identifier: NCT03381872.

Impact of Intravascular Imaging-Guided Stent Optimization According to Clinical Presentation in Patients Undergoing Complex PCI.

BACKGROUND: It is unclear whether the beneficial effects of intravascular imaging-guided stent optimization vary by clinical presentation during complex percutaneous coronary intervention (PCI). OBJECTIVES: In this prespecified, stratified subgroup analysis from RENOVATE-COMPLEX-PCI (Randomized Controlled Trial of Intravascular Imaging Guidance versus Angiography-Guidance on Clinical Outcomes After Complex PCI), we sought to compare the outcomes between intravascular imaging vs angiography guidance according to clinical presentation. METHODS: Patients with complex coronary artery lesions were randomly assigned to undergo either intravascular imaging-guided PCI or angiography-guided PCI in a 2:1 ratio. The primary endpoint was target vessel failure (TVF), which is a composite of cardiac death, target vessel-related myocardial infarction, or clinically driven target vessel revascularization. RESULTS: Of 1,639 patients, 832 (50.8%) presented with acute coronary syndrome (ACS) and 807 (49.2%) with chronic coronary syndrome. During a median follow-up of 2.1 years (Q1-Q3: 1.4-3.0 years), there was no significant interaction between the treatment effect of intravascular imaging and clinical presentation (P for interaction = 0.19). Among patients with ACS, the incidences of TVF were 10.4% in the intravascular imaging group and 14.6% in the angiography group (HR: 0.74; 95% CI: 0.48-1.15; P = 0.18). Among patients with CCS, the incidences of TVF were 5.0% in the intravascular imaging group and 10.4% in the angiography group (HR: 0.46; 95% CI: 0.27-0.80; P = 0.006). Achieving stent optimization by intravascular imaging resulted in a reduced risk of TVF among patients with ACS who were randomly assigned to intravascular imaging-guided PCI for complex coronary lesions (optimized vs unoptimized, 6.5% vs 14.1%; HR: 0.49; 95% CI: 0.27-0.87; P = 0.02) but not those with CCS (5.4% vs 4.7%, HR: 1.18; 95% CI: 0.53-2.59; P = 0.69). CONCLUSIONS: No significant interaction was observed between the benefits of intravascular imaging and clinical presentation in the risk of TVF. Stent optimization by intravascular imaging was particularly important for ACS patients. (Intravascular Imaging- Versus Angiography-Guided Percutaneous Coronary Intervention For Complex Coronary Artery Disease [RENOVATE]; NCT03381872).

Intravascular Imaging-Guided Optimization of Complex Percutaneous Coronary Intervention by Sex: A Subgroup Analysis of the RENOVATE-COMPLEX-PCI Trial.

Importance: There have been heterogeneous results related to sex differences in prognosis after percutaneous coronary artery intervention (PCI) for complex coronary artery lesions. Objective: To evaluate potential differences in outcomes with intravascular imaging-guided PCI of complex coronary artery lesions between women and men. Design, Setting, and Participants: This prespecified substudy evaluates the interaction of sex in the investigator-initiated, open-label, multicenter RENOVATE-COMPLEX-PCI randomized clinical trial, which demonstrated the superiority of intravascular imaging-guided PCI compared with angiography-guided PCI in patients with complex coronary artery lesions. The trial was conducted at 20 sites in Korea. Patients with complex coronary artery lesions undergoing PCI were enrolled between May 2018 and May 2021, and the median (IQR) follow-up period was 2.1 (1.4-3.0) years. Data were analyzed from December 2022 to December 2023. Interventions: After diagnostic coronary angiography, eligible patients were randomly assigned in a 2:1 ratio to receive intravascular imaging-guided PCI or angiography-guided PCI. The choice and timing of the intravascular imaging device were left to the operators' discretion. Main Outcomes and Measures: The primary end point was target vessel failure, defined as a composite of cardiac death, target vessel-related myocardial infarction, or clinically driven target vessel revascularization. Secondary end points included individual components of the primary end point. Results: Of 1639 included patients, 339 (20.7%) were women, and the mean (SD) age was 65.6 (10.2) years. There was no difference in the risk of the primary end point between women and men (9.4% vs 8.3%; adjusted hazard ratio [HR], 1.39; 95% CI, 0.89-2.18; P = .15). Intravascular imaging-guided PCI tended to have lower incidence of the primary end point than angiography-guided PCI in both women (5.2% vs 14.5%; adjusted HR, 0.34; 95% CI, 0.15-0.78; P = .01) and men (8.3% vs 11.7%; adjusted HR, 0.72; 95% CI, 0.49-1.05; P = .09) without significant interaction (P for interaction = .86). Conclusions and Relevance: In patients undergoing complex PCI, compared with angiographic guidance, intravascular imaging guidance was associated with similar reduction in the risk of target vessel failure among women and men. The treatment benefit of intravascular imaging-guided PCI showed no significant interaction between treatment strategy and sex. Trial Registration: ClinicalTrials.gov Identifier: NCT03381872.

Cost-Effectiveness of Intravascular Imaging-Guided Complex PCI: Prespecified Analysis of RENOVATE-COMPLEX-PCI Trial.

BACKGROUND: Although clinical benefits of intravascular imaging-guided percutaneous coronary intervention (PCI) in patients with complex coronary artery lesions have been observed in previous trials, the cost-effectiveness of this strategy is uncertain. METHODS: RENOVATE-COMPLEX-PCI (Randomized Controlled Trial of Intravascular Imaging Guidance vs Angiography-Guidance on Clinical Outcomes After Complex Percutaneous Coronary Intervention) was conducted in Korea between May 2018 and May 2021. This prespecified cost-effectiveness substudy was conducted using Markov model that simulated 3 states: (1) post-PCI, (2) spontaneous myocardial infarction, and (3) death. A simulated cohort was derived from the intention-to-treat population, and input parameters were extracted from either the trial data or previous publications. Cost-effectiveness was evaluated using time horizon of 3 years (within trial) and lifetime. The primary outcome was incremental cost-effectiveness ratio (ICER), an indicator of incremental cost on additional quality-adjusted life years (QALYs) gained, in intravascular imaging-guided PCI compared with angiography-guided PCI. The current analysis was performed using the Korean health care sector perspective with reporting the results in US dollar (1200 Korean Won, ₩=1 dollar, $). Willingness to pay threshold was $35 000 per QALY gained. RESULTS: A total of 1639 patients were included in the trial. During 3-year follow-up, medical costs ($8661 versus $7236; incremental cost, $1426) and QALY (2.34 versus 2.31; incremental QALY, 0.025) were both higher in intravascular imaging-guided PCI than angiography-guided PCI, resulting incremental cost-effectiveness ratio of $57 040 per QALY gained within trial data. Conversely, lifetime simulation showed total cumulative medical cost was reversed between the 2 groups ($40 455 versus $49 519; incremental cost, -$9063) with consistently higher QALY (8.24 versus 7.89; incremental QALY, 0.910) in intravascular imaging-guided PCI than angiography-guided PCI, resulting in a dominant incremental cost-effectiveness ratio. Consistently, 70% of probabilistic iterations showed cost-effectiveness of intravascular imaging-guided PCI in probabilistic sensitivity analysis. CONCLUSIONS: The current cost-effectiveness analysis suggests that imaging-guided PCI is more cost-effective than angiography-guided PCI by reducing medical cost and increasing quality-of-life in complex coronary artery lesions in long-term follow-up. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03381872.

Native PLGA nanoparticles attenuate Aß-seed induced tau aggregation under in vitro conditions: potential implication in Alzheimer's disease pathology.

Evidence suggests that beta-amyloid (Aß)-induced phosphorylation/aggregation of tau protein plays a critical role in the degeneration of neurons and development of Alzheimer's disease (AD), the most common cause of dementia affecting the elderly population. Many studies have pursued a variety of small molecules, including nanoparticles conjugated with drugs to interfere with Aß and/or tau aggregation/toxicity as an effective strategy for AD treatment. We reported earlier that FDA approved PLGA nanoparticles without any drug can attenuate Aß aggregation/toxicity in cellular/animal models of AD. In this study, we evaluated the effects of native PLGA on Aß seed-induced aggregation of tau protein using a variety of biophysical, structural and spectroscopic approaches. Our results show that Aß1-42 seeds enhanced aggregation of tau protein in the presence and absence of heparin and the effect was attenuated by native PLGA nanoparticles. Interestingly, PLGA inhibited aggregation of both 4R and 3R tau isoforms involved in the formation of neurofibrillary tangles in AD brains. Furthermore, Aß seed-induced tau aggregation in the presence of arachidonic acid was suppressed by native PLGA. Collectively, our results suggest that native PLGA nanoparticles can inhibit the Aß seed-induced aggregation of different tau protein isoforms highlighting their therapeutic implication in the treatment of AD.

Intravascular Imaging-Guided Percutaneous Coronary Intervention Before and After Standardized Optimization Protocols.

BACKGROUND: Although benefits of intravascular imaging (IVI) in percutaneous coronary intervention (PCI) have been observed in previous studies, it is not known whether changes in contemporary practice, especially with application of standardized optimization protocols, have improved clinical outcomes. OBJECTIVES: The authors sought to investigate whether clinical outcomes of IVI-guided PCI are different before and after the application of standardized optimization protocols in using IVI. METHODS: 2,972 patients from an institutional registry (2008-2015, before application of standardized optimization protocols, the past group) and 1,639 patients from a recently published trial (2018-2021 after application of standardized optimization protocols, the present group) were divided into 2 groups according to use of IVI. The primary outcome was 3-year target vessel failure (TVF), a composite of cardiac death, target vessel myocardial infarction, or target vessel revascularization. RESULTS: Significant reduction of TVF was observed in the IVI-guided PCI group compared with the angiography-guided PCI group (10.0% vs 6.7%; HR: 0.77; 95% CI: 0.61-0.97; P = 0.027), mainly driven by reduced cardiac death or myocardial infarction in both past and present IVI-guided PCI groups. When comparing past IVI and present IVI groups, TVF was significantly lower in the present IVI group (8.5% vs 5.1%; HR: 0.63; 95% CI: 0.42-0.94; P = 0.025), with the difference being driven by reduced target vessel revascularization in the present IVI group. Consistent results were observed in inverse-probability-weighting adjusted analysis. CONCLUSIONS: IVI-guided PCI improved clinical outcomes more than angiography-guided PCI. In addition, application of standardized optimization protocols when using IVI further improved clinical outcomes after PCI. (Intravascular Imaging- Versus Angiography-Guided Percutaneous Coronary Intervention For Complex Coronary Artery Disease [RENOVATE-COMPLEX-PCI]; NCT03381872; and the institutional cardiovascular catheterization database of Samsung Medical Center: Long-Term Outcomes and Prognostic Factors in Patient Undergoing CABG or PCI; NCT03870815).

Intravascular Imaging in Patients With Complex Coronary Lesions and Chronic Kidney Disease.

Importance: As patients with chronic kidney disease (CKD) are more likely to have complex coronary lesions, intravascular imaging guidance in percutaneous coronary intervention (PCI) for this population could be potentially beneficial. Objectives: To investigate whether the outcomes of intravascular imaging-guided procedural optimization would be different according to the presence of CKD. Design, Setting, and Participants: This was a prespecified substudy of RENOVATE-COMPLEX-PCI, a recently published multicenter randomized clinical trial in Korea studying the benefits of intravascular imaging for complex coronary lesions. Patients with complex coronary lesions, with or without CKD, were enrolled between May 2018 and May 2021. Data were analyzed from January to June 2023. Interventions: PCI in each group was done either under the guidance of intravascular imaging or angiography alone. Main Outcomes and Measures: The primary end point was target vessel failure (TVF) at the 3-year point, defined as a composite of cardiac death, target vessel-related myocardial infarction, or clinically driven target vessel revascularization. Results: A total of 1639 patients (1300 male [79.3%]) treated with PCI for complex coronary lesions were stratified into CKD (296 participants) and non-CKD (1343 participants) groups. The mean (SD) age of each group was 70.3 (9.4) and 64.5 (10.1) years, and mean (SD) estimated serum creatinine was 2.9 (5.3) and 0.8 (0.2) mg/dL for CKD and non-CKD groups, respectively. Intravascular imaging-guided revascularization was associated with significantly lower incidence of the primary end point compared with angiography-guided revascularization in both CKD (13.3% vs 23.3%; hazard ratio [HR], 0.51; 95% CI, 0.27-0.93; P = .03) and non-CKD (6.4% vs 9.9%; HR, 0.66; 95% CI, 0.44-0.99; P = .05) groups. The significantly lower incidence of the primary end point was mainly associated with the lower risk of cardiac death or target vessel-related myocardial infarction (9.4% vs 22.2%; HR, 0.39; 95% CI, 0.20-0.76; P = .006) in the CKD group and by target vessel revascularization (3.0% vs 5.5%; HR, 0.55; 95% CI, 0.30-0.99; P = .05) in the non-CKD group. Those with a glomerular filtration rate of at least 30 mL/min/1.73m2 and less than 60 ml/kg/1.73m2 showed the greatest benefit from imaging-guided complex PCI (8.8% vs 21.2%; HR, 0.28; 95% CI, 0.11-0.68; P = .02). Conclusions and Relevance: In this prespecified cohort substudy of the Randomized Controlled Trial of Intravascular Imaging Guidance versus Angiography-Guidance on Clinical Outcomes After Complex Percutaneous Coronary Intervention trial, intravascular imaging guidance showed clinical benefit over angiography guidance in reducing the risk of TVF, regardless of the presence of CKD. The greatest benefits of imaging-guided complex PCI were observed in stage 3 CKD. Trial Registration: ClinicalTrials.gov Identifier: NCT03381872.

Clinical Benefit of Intravascular Imaging Compared With Conventional Angiography in Left Main Coronary Artery Intervention.

BACKGROUND: The RENOVATE-COMPLEX-PCI (Randomized Controlled Trial of Intravascular Imaging Guidance Versus Angiography-Guidance on Clinical Outcomes After Complex Percutaneous Coronary Intervention) demonstrated that intravascular imaging-guided percutaneous coronary intervention (PCI) improved clinical outcome compared with angiography-guided PCI for patients with complex coronary artery lesions. This study aims to assess whether the prognostic benefit of intravascular imaging-guided procedural optimization persists in patients undergoing PCI for left main coronary artery disease. METHODS: Of 1639 patients enrolled in the RENOVATE-COMPLEX-PCI, 192 patients with left main coronary artery disease were selected for the current prespecified substudy. Selected patients were randomly assigned to either the intravascular imaging-guided PCI group (n=138) or the angiography-guided PCI group (n=54). The primary end point was target vessel failure defined as a composite of cardiac death, target vessel-related myocardial infarction, or clinically driven target vessel revascularization. RESULTS: At a median follow-up of 2.1 years (interquartile range 1.1 to 3.0 years), intravascular imaging-guided PCI was associated with lower incidence of primary end point compared with angiography-guided PCI (6.8% versus 25.1%; hazard ratio, 0.31 [95% CI, 0.13-0.76]; P=0.010). This significant reduction in primary end point was mainly driven by a lower risk of cardiac death or spontaneous target vessel-related myocardial infarction (1.6% versus 12.7%; hazard ratio, 0.16 [95% CI, 0.03-0.82]; P=0.028). Intravascular imaging-guided PCI was independently associated with a lower risk of primary end point, even after adjusting for various clinical factors (hazard ratio, 0.29 [95% CI, 0.12-0.72]; P=0.007). CONCLUSIONS: Intravascular imaging-guided PCI showed clinical benefit over angiography-guided PCI for left main coronary artery disease in reducing the risk of cardiac death, target vessel-related myocardial infarction, or target vessel revascularization. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03381872.

Delivery of siRNA using cationic rosette nanotubes for gene silencing.

The quest for new therapeutic treatments for hereditary diseases has led to many advances in RNA interference (RNAi) and gene silencing. While this technique has the potential to address many problems, the key to its continued use is the development of effective delivery strategies that would reduce cellular toxicity and increase silencing efficiency. Rosette nanotubes (RNTs) are biomimetic supramolecular nanostructures formed through the self-assembly of hybrid guanine-cytosine (G∧C) DNA bases. Here, we used bioactive RNTs for siRNA delivery and gene silencing. Fifteen lysine-functionalized twin-G∧C motifs (KnT, n = 1 to 15) were synthesized using solid phase peptide synthesis to produce building blocks that self-assembled to produce cationic RNTs under physiological conditions. The intracellular uptake of siRNA delivered by the oligo-L-lysine RNTs was examined and it was found that the complexation of siRNA was affected by the cationic charges from the lysine residues and the length of RNTs formed, with the higher charged KnT RNTs delivering siRNA to the cells at a faster rate. In addition, by protecting siRNA from serum degradation, KnT RNTs were shown to deliver their cargo to the cells effectively via the endocytic pathway. A reduction in the expression (∼70%) of the target stat3 protein was observed during gene expression analysis in HCT116 and A549 cell lines.

P2Y12 Inhibitor Monotherapy Combined With Colchicine Following PCI in ACS Patients: The MACT Pilot Study.

BACKGROUND: After a brief period of dual antiplatelet therapy, P2Y12 inhibitor monotherapy in the absence of aspirin effectively reduces bleeding without increasing recurrent ischemia in patients undergoing percutaneous coronary intervention (PCI). In addition, early anti-inflammatory therapies may have clinical benefits in acute coronary syndrome (ACS) patients. OBJECTIVES: The aim of this study was to investigate the feasibility of ticagrelor or prasugrel P2Y12 inhibitor monotherapy combined with colchicine immediately after PCI in patients with ACS. METHODS: This was a proof-of-concept pilot trial. ACS patients treated with drug-eluting stents were included. On the day after PCI, low-dose colchicine (0.6 mg daily) was administered in addition to ticagrelor or prasugrel maintenance therapy, whereas aspirin therapy was discontinued. The primary outcome was any stent thrombosis at 3 months. The key secondary outcomes were platelet reactivity measured by the VerifyNow assay (Accriva) before discharge and a reduction in high-sensitivity C-reactive protein (hs-CRP) over 1 month. RESULTS: We enrolled 200 patients, 190 (95.0%) of whom completed the 3-month follow-up. The primary outcome occurred in 2 patients (1.0%): 1 definite and 1 probable stent thrombosis. The level of platelet reactivity overall was 27 ± 42 P2Y12 reaction units, and only 1 patient had high platelet reactivity (>208 P2Y12 reaction units). The hs-CRP levels decreased from 6.1 mg/L (IQR: 2.6-15.9 mg/L) at 24 hours after PCI to 0.6 mg/L (IQR: 0.4-1.2 mg/L) at 1 month (P < 0.001), and the prevalence of high-inflammation criteria (hs-CRP ≥2 mg/L) decreased from 81.8% to 11.8% (P < 0.001). CONCLUSIONS: In ACS patients undergoing PCI, it is feasible to discontinue aspirin therapy and administer low-dose colchicine on the day after PCI in addition to ticagrelor or prasugrel P2Y12 inhibitors. This approach is associated with favorable platelet function and inflammatory profiles. (Mono Antiplatelet and Colchicine Therapy [MACT]; NCT04949516).

Preclinical evaluation of manufacturable SARS-CoV-2 spike virus-like particles produced in Chinese Hamster Ovary cells.

BACKGROUND: As the COVID-19 pandemic continues to evolve, novel vaccines need to be developed that are readily manufacturable and provide clinical efficacy against emerging SARS-CoV-2 variants. Virus-like particles (VLPs) presenting the spike antigen at their surface offer remarkable benefits over other vaccine antigen formats; however, current SARS-CoV-2 VLP vaccines candidates in clinical development suffer from challenges including low volumetric productivity, poor spike antigen density, expression platform-driven divergent protein glycosylation and complex upstream/downstream processing requirements. Despite their extensive use for therapeutic protein manufacturing and proven ability to produce enveloped VLPs, Chinese Hamster Ovary (CHO) cells are rarely used for the commercial production of VLP-based vaccines. METHODS: Using CHO cells, we aimed to produce VLPs displaying the full-length SARS-CoV-2 spike. Affinity chromatography was used to capture VLPs released in the culture medium from engineered CHO cells expressing spike. The structure, protein content, and glycosylation of spikes in VLPs were characterized by several biochemical and biophysical methods. In vivo, the generation of neutralizing antibodies and protection against SARS-CoV-2 infection was tested in mouse and hamster models. RESULTS: We demonstrate that spike overexpression in CHO cells is sufficient by itself to generate high VLP titers. These VLPs are evocative of the native virus but with at least three-fold higher spike density. In vivo, purified VLPs elicit strong humoral and cellular immunity at nanogram dose levels which grant protection against SARS-CoV-2 infection. CONCLUSIONS: Our results show that CHO cells are amenable to efficient manufacturing of high titers of a potently immunogenic spike protein-based VLP vaccine antigen.

Virus-like particles (VLPs) have a structure that is similar to viruses but they cannot cause infection or illness. If VLPs are injected into the body they produce an immune response similar to that seen following infection by a virus. This means that VLPs can be used as vaccines against viruses that cause illness in people. Many drugs, named biologics, are manufactured using living cells, including cells that were originally derived from Chinese Hamster Ovaries (CHO cells). We developed a simple method to produce VLPs similar to the SARS-CoV-2 virus in CHO cells. We show that vaccination of rodents with these VLPs prevents them from becoming ill following infection with SARS-CoV-2. These VLPs could become a part of an alternative, easily produced vaccine for the prevention of COVID-19 in humans.

Clinical implication of ticagrelor monotherapy in patients with small vessel coronary artery disease: results from the TICO randomized trial.

Background: The aim of this study was to evaluate the efficacy and safety of ticagrelor monotherapy in patients with small vessel disease compared with ticagrelor-based DAPT within the Ticagrelor Monotherapy after 3 Months in the Patients Treated with New Generation Sirolimus Eluting Stent for Acute Coronary Syndrome (TICO) trial population. Methods: Reference vessel diameter ≤2.5 mm was considered as small vessel disease. We conducted a comparison of the incidence of target lesion failure (TLF) and Bleeding Academic Research Consortium (BARC) type 3 or 5 bleeding. TLF was defined as a composite of cardiac death, target lesion myocardial infarction, stent thrombosis, and target lesion revascularization. Results: 652 patients among 3,056 TICO population (21.3%) had small vessel disease. Patients with small vessel disease showed a higher rate of TLF compared to those without small vessel disease (2.9% vs. 1.0%, log-rank p < 0.001). The presence of small vessel disease emerged as an independent predictor for 1-year TLF (HR 2.84, 95% CI 1.54-5.25), while it did not show a significant association with bleeding complications. The 12-month TLF rate was 1.6% for ticagrelor monotherapy after 3-month DAPT, and 4.2% for ticagrelor-based 12-month DAPT (p = 0.059) in patients with small vessel disease (HR 0.38, 95% CI 0.14-1.04, p for interaction = 0.261). The incidence of BARC type 3 or 5 bleeding rate 2.5% for ticagrelor monotherapy after 3-month DAPT, and 5.6% for ticagrelor-based 12-month DAPT (p = 0.052) in patients with small vessel disease (HR 0.44, 95% CI 0.19-1.01, p for interaction = 0.322). In the 3-month landmark analysis, ticagrelor monotherapy significantly reduced BARC type 3 or 5 bleeding in patients with small vessel disease (HR 0.09, 95% CI 0.01-0.69, log-rank p = 0.005) while demonstrating a similar incidence of TLF compared to ticagrelor based 12-month DAPT during the 3-12 months period. Conclusions: There are no significant interactions between the antiplatelet strategy regarding the 12-month incidence of ischemic and bleeding complications. Ticagrelor monotherapy demonstrated a reduction in bleeding complications after a 3-month period of DAPT without increasing the rate of TLF, when compared to ticagrelor-based 12-month DAPT, specifically in patients with small vessel disease. Clinical Trial Registration: www.ClinicalTrials.gov, identifier, NCT02494895.

Effect of Cilostazol on Patients With Diabetes Who Underwent Endovascular Treatment for Peripheral Artery Disease.

Background No large-scale study has compared the clinical impact of triple antiplatelet therapy (TAPT: aspirin, clopidogrel, and cilostazol) and dual antiplatelet therapy (DAPT) on adverse limb events in patients with diabetes after endovascular therapy (EVT) for peripheral artery disease. Thus, we investigate the effect of cilostazol added to a DAPT on the clinical outcomes after EVT in patients with diabetes using a nationwide, multicenter, real-world registry. Methods and Results A total of 990 patients with diabetes who underwent EVT were enrolled from the retrospective cohorts of a Korean multicenter EVT registry and were divided according to the antiplatelet regimen (TAPT [n=350; 35.4%] versus DAPT [n=640; 64.6%]). After propensity score matching based on clinical characteristics, a total of 350 pairs were compared for clinical outcomes. The primary end points were major adverse limb events, a composite of major amputation, minor amputation, and reintervention. For the matched study groups, the lesion length was 125.4±102.0 mm, and severe calcification was observed in 47.4%. The technical success rate (96.9% versus 94.0%; P=0.102) and the complication rate (6.9% versus 6.6%; P>0.999) were similar between the TAPT and DAPT groups. At 2-year follow-up, the incidence of major adverse limb events (16.6% versus 19.4%; P=0.260) did not differ between the 2 groups. However, the TAPT group showed less minor amputation than the DAPT group (2.0% versus 6.3%; P=0.004). In multivariate analysis, TAPT was an independent predictor of minor amputation (adjusted hazard ratio, 0.354 [95% CI, 0.158-0.794]; P=0.012). Conclusions In patients with diabetes undergoing EVT for peripheral artery disease, TAPT did not decrease the incidence of major adverse limb events but may be associated with a decreased risk of minor amputation.

Parenting stress and interactive engagement behaviors in children with developmental delay.

BACKGROUND: In clinical practice, the importance of interactive engagement behaviors is overlooked in children with developmental problems other than autism spectrum disorder (ASD). Parenting stress affects children's development but lacks attention from clinicians. PURPOSE: This study aimed to identify the characteristics of interactive engagement behaviors and parenting stress among non-ASD children with developmental delays (DDs). We also analyzed whether engagement behaviors affect parenting stress. METHODS: At Gyeongsang National University Hospital, between May 2021 and October 2021, we retrospectively enrolled 51 consecutive patients diagnosed with DDs in language or cognition (but not ASD) in the delayed group and 24 typically developing children in the control group. The Korean version of the Parenting Stress Index-4 and Child Interactive Behavior Test were used to assess the participants. RESULTS: The median age of the delayed group was 31.0 months (interquartile range, 25.0-35.5 months); this group included 42 boys (82.4%). There were no intergroup differences in child age, child sex, parental age, parental educational background, mother's employment status, or marital status. Higher parenting stress (P<0.001) and fewer interactive engagement behaviors (P<0.001) were observed in the delayed group. Low parental acceptance and competence had the largest effects on total parenting stress in the delayed group. A mediation analysis revealed that DDs did not directly affect total parenting stress (ß=3.49, P=0.440). Instead, DDs contributed to total parenting stress, which was mediated by children's overall interactive engagement behaviors (ß=57.30, P<0.001). CONCLUSION: Interactive engagement behaviors were significantly reduced in non-ASD children with DDs and significantly mediated parenting stress. The importance of parenting stress and interactive behaviors in children with DDs should be further examined in clinical practice.