Development of potent pan-coronavirus fusion inhibitors with a new design strategy.

Development of potent and broad-spectrum drugs against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains one of the top priorities, especially in the cases of the emergence of mutant viruses and inability of current vaccines to prevent viral transmission. In this study, we have generated a novel membrane fusion-inhibitory lipopeptide IPB29, which is currently under clinical trials; herein, we report its design strategy and preclinical data. First, we surprisingly found that IPB29 with a rigid linker between the peptide sequence and lipid molecule had greatly improved α-helical structure and antiviral activity. Second, IPB29 potently inhibited a large panel of SARS-CoV-2 variants including the previously and currently circulating viruses, such as Omicron XBB.5.1 and EG.5.1. Third, IPB29 could also cross-neutralize the bat- and pangolin-isolated SARS-CoV-2-related CoVs (RatG13, PCoV-GD, and PCoV-GX) and other human CoVs (SARS-CoV, MERS-CoV, HCoV-NL63, and HCoV-229E). Fourth, IPB29 administrated as an inhalation solution (IPB29-IS) in Syrian hamsters exhibited high therapeutic and preventive efficacies against SARS-CoV-2 Delta or Omicron variant. Fifth, the pharmacokinetic profiles and safety pharmacology of IPB29-IS were extensively characterized, providing data to support its evaluation in humans. In conclusion, our studies have demonstrated a novel design strategy for viral fusion inhibitors and offered an ideal drug candidate against SARS-CoV-2 and other coronaviruses.

Characterization of novel HIV fusion-inhibitory lipopeptides with the M-T hook structure.

Combination antiretroviral therapy (cART) has significantly improved the survival of HIV-infected individuals, but long-term treatment can cause side-effects and drug resistance; thus, the development of new antivirals is of importance. We previously identified an M-T hook structure and accordingly designed short-peptide fusion inhibitor 2P23, which mainly targets the gp41 pocket site and displays potent, broad-spectrum anti-HIV activity. In this study, we continuingly characterized the amino acid sequences of peptide and lipopeptide-based inhibitors containing the M-T hook residues. Among a group of lipopeptides, stearic acid (C18)-modified LP-25 and LP-29 exhibited greatly improved inhibitions against divergent HIV-1 subtypes and drug-resistant mutants. LP-25 and LP-29 were evaluated in rhesus macaques, and the ex vivo inhibition data demonstrated their potent, long-lasting in vivo anti-HIV activity, with LP-25 much better than LP-29. Both the lipopeptides displayed high α-helicity, thermostability and binding ability to a target-mimic peptide, and they were metabolically stable when treated with high temperature, proteolytic enzymes, human or monkey sera and human liver microsomes. Therefore, our studies have provided critical information for understanding the structure-activity relationship of HIV fusion inhibitors with the M-T hook structure and offered novel candidates for drug development.

Radiofrequency ablation using the ThermoCool SmartTouch Catheter guided by ablation index versus antiarrhythmic drugs in atrial fibrillation treatment in China: a cost-consequence analysis.

Aim: To evaluate the costs and consequences of two front-line atrial fibrillation (AF) treatments from Chinese healthcare system perspective: radiofrequency catheter ablation (RFCA) using ThermoCool SmartTouch Catheter guided by Ablation Index (STAI), in comparison to antiarrhythmic drugs (AADs). Patients & methods: We simulated clinical and economic consequences for AF patients initially receiving STAI or AADs using a short-term decision tree model leading to a 10-year long-term Markov model. The model projected both clinical consequences and costs associated with, among others, AF, heart failure (HF), strokes, and deaths due to AF or AF related complications. Data informing the models included combination of a local real-world study and published clinical studies. Results: STAI was advantageous versus AADs on all 4 main clinical outcomes evaluated; AF: 25.83% lower (12.84% vs 38.67%), HF: 2.22% lower (1.33% vs 3.55%), stroke or post stroke: 1.82% lower (10.00% vs 11.82%) and deaths due to AF or AF related complications: 0.64% lower (4.11% vs 4.75%). The average total cost per patient in STAI group was ¥16,682 lower (¥123,124 vs ¥139,806). The one-way sensitivity analysis indicated that the difference in total cost was most sensitive to annual AF recurrence probability in AADs-treated patients. Probabilistic sensitivity analysis indicated a 98.5% probability that RFCA treatment would result in cost savings by the end of the 10th year. Conclusion: Radiofrequency catheter ablation using SmartTouch catheter guided by Ablation Index was superior to AADs as the first-line AF treatment in Chinese setting with better clinical outcomes and at lower costs over a 10-year time horizon.

Resveratrol protects against doxorubicin-induced cardiotoxicity by attenuating ferroptosis through modulating the MAPK signaling pathway.

Doxorubicin (Dox) is a widely used antitumor agent with dose-dependent and cumulative cardiotoxic effects. Resveratrol (Res) is a natural non-flavonoid polyphenol that can potentially provide cardiovascular benefits. We aimed to estimate the protective effect of Res on Dox-induced cardiotoxicity (DIC) and explore whether it was related to attenuating ferroptosis. We established DIC models in C57BL/6 J mice, H9C2 cardiomyoblasts, and neonatal rat cardiomyocytes (NRCMs). We further treated H9C2 cells with RSL3, a ferroptosis agonist, to investigate whether Res exerted protective effects through inhibiting ferroptosis. Ferrostatin-1 (Fer-1) was applied to suppress ferroptosis. Dox treatment caused cardiac dysfunction and resulted in apparent ferroptotic damage in cardiac tissue, involving increased iron accumulation, glutathione depletion, increased expression of ferroptosis-related proteins, and decreased expression of glutathione peroxidase 4, which were alleviated by Fer-1 and Res administration. These findings were also confirmed in Dox-treated H9C2 cells and NRCMs, with Fer-1 and Res effectively attenuating Dox-induced cytotoxicity and ferroptosis. Furthermore, Res protected H9C2 cells from RSL3-induced ferroptotic cell death, and the protective effect was similar to that of Fer-1. Both Dox and RSL3 treatment increased the phosphorylation levels of mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase, p38, and c-Jun N-terminal kinases; however, these changes were hindered by Res. This study demonstrates that Res effectively alleviates DIC by suppressing ferroptosis possibly through modulating the MAPK signaling pathway. Our results highlight that targeting ferroptosis can be a potential cardioprotective strategy for DIC.

Design of a bifunctional pan-sarbecovirus entry inhibitor targeting the cell receptor and viral fusion protein.

Development of highly effective antivirals that are robust to viral evolution is a practical strategy for combating the continuously evolved severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Inspired by viral multistep entry process, we here focus on developing a bispecific SARS-CoV-2 entry inhibitor, which acts on the cell receptor angiotensin converting enzyme 2 (ACE2) and viral S2 fusion protein. First, we identified a panel of diverse spike (S) receptor-binding domains (RBDs) and found that the RBD derived from Guangdong pangolin coronavirus (PCoV-GD) possessed the most potent antiviral potency. Next, we created a bispecific inhibitor termed RBD-IPB01 by genetically linking a peptide fusion inhibitor IPB01 to the C-terminal of PCoV-GD RBD, which exhibited greatly increased antiviral potency via cell membrane ACE2 anchoring. Promisingly, RBD-IPB01 had a uniformly bifunctional inhibition on divergent pseudo- and authentic SARS-CoV-2 variants, including multiple Omicron subvariants. RBD-IPB01 also showed consistently cross-inhibition of other sarbecoviruses, including SARS-CoV, PCoV-GD, and Guangxi pangolin coronavirus (PCoV-GX). RBD-IPB01 displayed low cytotoxicity, high trypsin resistance, and favorable metabolic stability. Combined, our studies have provided a tantalizing insight into the design of broad-spectrum and potent antiviral agent. IMPORTANCE Ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) evolution and spillover potential of a wide variety of sarbecovirus lineages indicate the importance of developing highly effective antivirals with broad capability. By directing host angiotensin converting enzyme 2 receptor and viral S2 fusion protein, we have created a dual-targeted virus entry inhibitor with high antiviral potency and breadth. The inhibitor receptor-binding domain (RBD)-IPB01 with the Guangdong pangolin coronavirus (PCoV-GD) spike RBD and a fusion inhibitor IPB01 displays bifunctional cross-inhibitions on pseudo- and authentic SARS-CoV-2 variants including Omicron, as well as on the sarbecoviruses SARS-CoV, PCoV-GD, and Guangxi pangolin coronavirus. RBD-IPB01 also efficiently inhibits diverse SARS-CoV-2 infection of human Calu-3 cells and blocks viral S-mediated cell-cell fusion with a dual function. Thus, the creation of such a bifunctional inhibitor with pan-sarbecovirus neutralizing capability has not only provided a potential weapon to combat future SARS-CoV-2 variants or yet-to-emerge zoonotic sarbecovirus, but also verified a viable strategy for the designing of antivirals against infection of other enveloped viruses.

Broad-spectrum anti-HIV activity and high drug resistance barrier of lipopeptide HIV fusion inhibitor LP-19.

Lipopeptide-19, a HIV fusion inhibitor (LP-19), has showed potent anti-HIV activity. However, there is still limited information of the antiviral activity against different subtype clinical isolates and the drug resistance barrier of LP-19. Therefore, 47 HIV clinical isolates were selected for this study. The viral features were identified, in which 43 strains are CCR5 tropisms, and 4 strains are CCR5/CXCR4 tropisms, and there are 6 subtype B', 15 CRF01_AE, 14 CRF07_BC, 2 CRF08_BC and 10 URF strains. These 47 viruses were used to detected and analyze the inhibitory activities of LP-19. The results showed that the average 50% inhibitory concentration (IC50) and 90% inhibitory concentration (IC90) of LP-19 were 0.50 nM and 1.88 nM, respectively. The average IC50 of LP-19 to B', CRF01_AE, CRF07_BC, CRF08_BC, and URF strains was 0.76 nM, 0.29 nM, 0.38 nM, 0.85 nM, and 0.44 nM, respectively. C34 and Enfuvirtide (T-20), two fusion inhibitors, were compared on the corresponding strains simultaneously. The antiviral activity of LP-19 was 16.7-fold and 86-fold higher than that of C34 and T-20. The antiviral activity of LP-19, C34, and T-20 were further detected and showed IC50 was 0.15 nM, 1.02 nM, and 66.19 nM, respectively. IC50 of LP-19 was about 7-fold and 441-fold higher compared to C34 and T-20 against HIV-1 NL4-3 strains. NL4-3 strains were exposed to increasing concentrations of LP-19 and C34 in MT-2 cell culture. The culture virus was sequenced and analyzed. The results showed that A243V mutation site identified at weeks 28, 32, 38, and 39 of the cell culture in the gp41 CP (cytoplasmic domain) region. NL4-3/A243V viruses containing A243V mutation were constructed. Comparing the antiviral activities of LP-19 against HIV NL4-3 to HIV strains (only 1.3-fold), HIV did not show drug resistance when LP-19 reached 512-fold of the initial concentration under the drug pressure for 39 weeks. This study suggests that LP-19 has broad-spectrum anti-HIV activity, and high drug resistance barrier.

Design and characterization of novel SARS-CoV-2 fusion inhibitors with N-terminally extended HR2 peptides.

Development of potent and broad-spectrum antivirals against SARS-CoV-2 remains one of top priorities, especially in the case of that current vaccines cannot effectively prevent viral transmission. We previously generated a group of fusion-inhibitory lipopeptides, with one formulation being evaluated under clinical trials. In this study, we dedicated to characterize the extended N-terminal motif (residues 1161-1168) of the so-called spike (S) heptad repeat 2 (HR2) region. Alanine scanning analysis of this motif verified its critical roles in S protein-mediated cell-cell fusion. Using a panel of HR2 peptides with the N-terminal extensions, we identified a peptide termed P40, which contained four extended N-terminal residues (VDLG) and exhibited improved binding and antiviral activities, whereas the peptides with further extensions had no such effects. Then, we developed a new lipopeptide P40-LP by modifying P40 with cholesterol, which exhibited dramatically increased activities in inhibiting SARS-CoV-2 variants including divergent Omicron sublineages. Moreover, P40-LP displayed a synergistic effect with IPB24 lipopeptide that was designed containing the C-terminally extended residues, and it could effectively inhibit other human coronaviruses, including SARS-CoV, MERS-CoV, HCoV-229E, and HCoV-NL63. Taken together, our results have provided valuable insights for understanding the structure-function relationship of SARS-CoV-2 fusion protein and offered novel antiviral strategies to fight against the COVID-19 pandemic.

Development of highly effective LCB1-based lipopeptides targeting the spike receptor-binding motif of SARS-CoV-2.

LCB1 is a computationally designed 56-mer miniprotein targeting the spike (S) receptor-binding motif of SARS-CoV- 2 with high potent activity (Science, 2020; Cell host microbe, 2021); however, recent studies have demonstrated that emerging SARS-CoV-2 variants are highly resistant to LCB1's inhibition. In this study, we first identified a truncated peptide termed LCB1v8, which maintained the high antiviral potency. Then, a group of lipopeptides were generated by modifying LCB1v8 with diverse lipids, and of two lipopeptides, the C-terminally stearicacid-conjugtaed LCB1v17 and cholesterol-conjugated LCB1v18, were highly effective in inhibiting both S protein-pseudovirus and authentic SARS-CoV-2 infections. We further showed that LCB1-based inhibitors had similar α-helicity and thermostability in structure and bound to the target-mimic RBD protein with high affinity, and the lipopeptides exhibited greatly enhanced binding with the viral and cellular membranes, improved inhibitory activities against emerging SARS-CoV-2 variants. Moreover, LCB1v18 was validated with high preventive and therapeutic efficacies in K18-hACE2 transgenic mice against lethal SARS-CoV-2 challenge. In conclusion, our studies have provided important information for understanding the structure and activity relationship (SAR) of LCB1 inhibitor and would guide the future development of novel antivirals.

Is catheter-based foam sclerotherapy more effective than direct foam sclerotherapy when combined with high ligation for the treatment of primary great saphenous vein incompetence?

BACKGROUND: To retrospectively analyze the short-term outcomes of catheter-based versus direct foam sclerotherapy when combined with high ligation (HL) for the treatment of great saphenous vein (GSV) incompetence. METHODS: From July 2018 to October 2019, a total of 82 lower limbs of 70 patients with GSV incompetence received HL combined with catheter-based foam sclerotherapy (CFS group) or direct foam sclerotherapy (DFS group) for GSV proximal trunk. Among them, 40 limbs of 36 patients were treated with CFS, and 42 limbs of 34 patients were treated with DFS. The occlusion of GSV proximal trunk was evaluated with venous duplex ultrasound examinations; Venous Clinical Severity Scores (VCSS) was used to assess clinical improvement; Aberdeen Varicose Veins Questionnaire (AVVQ) was used to assess quality-of-life scores; and Complications was used for the safety evaluation. RESULTS: At day 7 post-operatively, complete occlusion of proximal trunk of the GSV was achieved in 92.5% legs of the CFS group and 71.4% of the DFS group (p = 0.014). Additionally, anterograde flow was found in 7.5% legs of the CFS group and 26.2% of the DFS group (p = 0.025). No significant differences in the occurrence of complications were observed between the two groups. The median follow-up was 285.5 days in the DFS group and 318 days in the CFS group (p = 0.140). VCSS and AVVQ reduction were significant in both CFS group and DFS group (5.3 ± 2.5, 5.5 ± 2.4, p < 0.001 for VCSS; 15.9 ± 8.0, 16.3 ± 8.6, p < 0.001 for AVVQ), but no significant difference were observed between two groups (p = 0.655 for VCSS, p = 0.934 for AVVQ). CONCLUSIONS: Although the occlusion of great saphenous vein proximal trunk were different, two modalities result in similar clinical and quality-of-life improvements. DFS is a feasible alternative to CFS when combined with HL.

Spinal Cord Stimulation Attenuates Neural Remodeling, Inflammation, and Fibrosis After Myocardial Infarction.

OBJECTIVES: Spinal cord stimulation (SCS) is an established neuromodulation method that regulates the cardiac autonomic system. However, the biological mechanisms of the therapeutic effects of SCS after myocardial infarction (MI) remain unclear. MATERIALS AND METHODS: Twenty-five rabbits were divided into five groups: SCS-MI (voltage: 0.5 v; pulse width: 0.2 ms; 50 Hz; ten minutes on and 30 minutes off; two weeks; n = 5), MI (n = 5), sham SCS-MI (voltage: 0 v; two weeks; n = 5), sham MI (n = 5), and blank control (n = 5) groups. MI was induced by permanent left anterior descending artery ligation. SCS-MI and sham SCS-MI rabbits received the corresponding interventions 24 hours after MI. Autonomic remodeling was evaluated using enzyme-linked immunosorbent assay and immunohistochemistry. Inflammation and myocardial fibrosis were assessed using immunohistochemistry, quantitative polymerase chain reaction, hematoxylin and eosin staining, Masson staining, and Western blot. RESULTS: SCS improved the abnormal systemic autonomic activity. Cardiac norepinephrine decreased after MI (p < 0.01) and did not improve with SCS. Cardiac acetylcholine increased with SCS compared with the MI group (p < 0.05). However, no difference was observed between the MI and blank control groups. Growth-associated protein 43 (p < 0.001) and tyrosine hydroxylase (p < 0.001) increased whereas choline acetyltransferase (p < 0.05) decreased in the MI group compared with the blank control group. These changes were attenuated with SCS. SCS inhibited inflammation, decreased the ratio of phosphorylated-Erk to Erk (p < 0.001), and increased the ratio of phosphorylated-STAT3 to STAT3 (p < 0.001) compared with the MI group. Myocardial fibrosis was also attenuated by SCS. CONCLUSIONS: SCS improved abnormal autonomic activity after MI, leading to reduced inflammation, reactivation of STAT3, and inhibition of Erk. Additionally, SCS attenuated myocardial fibrosis. Our results warrant future studies of biological mechanisms of the therapeutic effects of SCS after MI.

Susceptibility and Resistance of SARS-CoV-2 Variants to LCB1 and Its Multivalent Derivatives.

LCB1 is a computationally designed three-helix miniprotein that precisely targets the spike (S) receptor-binding motif (RBM) of SARS-CoV-2, exhibiting remarkable antiviral efficacy; however, emerging SARS-CoV-2 variants could substantially compromise its neutralization effectiveness. In this study, we constructed two multivalent LCB1 fusion proteins termed LCB1T and LCB1T-Fc, and characterized their potency in inhibiting SARS-CoV-2 pseudovirus and authentic virus in vitro. In the inhibition of various SARS-CoV-2 variants, the two LCB1 fusion proteins exhibited markedly improved inhibitory activities compared to LCB1 as anticipated; however, it was observed that relative to the D614G mutation hosting variant, the variants Delta, Lambda, and Omicron BQ.1.1, XBB, XBB.1.5, and EG.5.1 caused various degrees of resistance to the two fusion proteins' inhibition, with XBB, XBB.1.5, and EG.5.1 variants showing high-level resistance. Moreover, we demonstrated that bat coronavirus RaTG13 and pangolin coronavirus PCoV-GD/PCoV-GX were highly sensitive to two LCB1 fusion proteins, but not LCB1, inhibition. Importantly, our findings revealed a notable decrease in the blocking capacity of the multivalent LCB1 inhibitor on the interaction between the virus's RBD/S and the cell receptor ACE2 when confronted with the XBB variant compared to WT and the Omicron BA.1 variant. In conclusion, our studies provide valuable insights into the antiviral profiling of multivalent LCB1 inhibitors and offer a promising avenue for the development of novel broad-spectrum antiviral therapeutics.

CAR designs for solid tumors: overcoming hurdles and paving the way for effective immunotherapy.

Chimeric antigen receptor T cell (CAR-T) therapy has revolutionized immunotherapy by modifying patients' immune cells genetically. By expressing CARs, these modified cells can specifically identify and eliminate tumor cells. The success of CAR-T therapy in hematological malignancies, such as leukemia and lymphoma, has been remarkable. Numerous studies have reported improved patient outcomes and increased survival rates. However, the application of CAR-T therapy in treating solid tumors faces significant challenges. Solid tumors possess complex microenvironments containing stromal cells, extracellular matrix components, and blood vessels. These factors can impede the infiltration and persistence of CAR-T cells within the tumor. Additionally, the lack of target antigens exclusively expressed on tumor cells raises concerns about off-target effects and potential toxicity. This review aims to discuss advancements achieved by CAR-T therapy in solid tumors and the clinical outcomes in the realm of solid tumors.

Resistance profile and mechanism of severe acute respiratory syndrome coronavirus-2 variants to LCB1 inhibitor targeting the spike receptor-binding motif.

LCB1 is a 56-mer miniprotein computationally designed to target the spike (S) receptor-binding motif of SARS-CoV-2 with potent in vitro and in vivo inhibitory activities (Cao et al., 2020; Case et al., 2021). However, the rapid emergence and epidemic of viral variants have greatly impacted the effectiveness of S protein-targeting vaccines and antivirals. In this study, we chemically synthesized a peptide-based LCB1 inhibitor and characterized the resistance profile and underlying mechanism of SARS-CoV-2 variants. Among five variants of concern (VOCs), we found that pseudoviruses of Beta, Gamma, and Omicron were highly resistant to the LCB1 inhibition, whereas the pseudoviruses of Alpha and Delta as well as the variant of interest (VOI) Lambda only caused mild resistance. By generating a group of mutant viruses carrying single or combination mutations, we verified that K417N and N501Y substitutions in RBD critically determined the high resistance phenotype of VOCs. Furthermore, a large panel of 85 pseudoviruses with naturally occurring RBD point-mutations were generated and applied to LCB1, which identified that E406Q, K417N, and L455F conferred high-levels of resistance, when Y505W caused a ∼6-fold resistance fold-change. We also showed that the resistance mutations could greatly weaken the binding affinity of LCB1 to RBD and thus attenuated its blocking capacity on the interaction between RBD and the cell receptor ACE2. In conclusion, our data have provided crucial information for understanding the mechanism of SARS-CoV-2 resistance to LCB1 and will guide the design strategy of novel LCB1-based antivirals against divergent VOCs and evolutionary mutants.

Potent inhibition of diverse Omicron sublineages by SARS-CoV-2 fusion-inhibitory lipopeptides.

The emergence and rapid spreading of SARS-CoV-2 variants of concern (VOCs) have posed a great challenge to the efficacy of vaccines and therapeutic antibodies, calling for antivirals that can overcome viral evasion. We recently reported that SARS-CoV-2 fusion-inhibitory lipopeptides, IPB02V3 and IPB24, possessed the potent activities against divergent VOCs, including Alpha, Beta, Gamma, Delta, and the initial Omicron strain (B.1.1.529); however, multiple Omicron sublineages have emerged and BA.4/5 is now becoming predominant globally. In this study, we focused on characterizing the functionality of the spike (S) proteins derived from Omicron sublineages and their susceptibility to the inhibition of IPB02V3 and IPB24. We first found that the S proteins of BA.2, BA.2.12.1, BA.3, and BA.4/5 exhibited significantly increased cell fusion capacities compared to BA.1, whereas the pseudoviruses of BA.2.12.1, BA.3, and BA.4/5 had significantly increased infectivity relative to BA.1 or BA.2. Next, we verified that IPB02V3 and IPB24 also maintained their very high potent activities in inhibiting diverse Omicron sublineages, even with enhanced potencies relative to the inhibition on ancestral virus. Moreover, we demonstrated that evolved Omicron mutations in the inhibitor-binding heptad repeat 1 (HR1) site could impair the S protein-driven cell fusogenicity and infectivity, but none of single or combined mutations affected the antiviral activity of IPB02V3 and IPB24. Therefore, we believe that viral fusion inhibitors possess high potential to be developed as effective drugs for fighting SARS-CoV-2 variants including diverse Omicron sublineages.

Preparation of an Environmentally Friendly Nano-Insecticide through Encapsulation in Polymeric Liposomes and Its Insecticidal Activities against the Fall Armyworm, Spodoptera frugiperda.

The insecticide emamectin benzoate (EB) was formulated with nanoparticles composed of DSPE-PEG2000-NH2 by the co-solvent method to determine its adverse impacts on the environment and to reinforce its dispersion, adhesion, and biocompatibility. A good encapsulation efficiency (70.5 ± 1.5%) of EB loaded in DSPE-PEG2000-NH2 polymeric liposomes was confirmed. Dynamic light scattering (DLS), transmission electron microscopy (TEM), and contact angle meter measurements revealed that the DSPE-EB nanoparticles had a regular distribution, spherical shape, and good leaf wettability. The contact angle on corn leaves was 47.26°, and the maximum retention was higher than that of the reference product. DSPE-EB nanoparticles had strong adhesion on maize foliage and a good, sustained release property. The efficacy trial showed that the DSPE-EB nanoparticles had a strong control effect on S. frugiperda larvae, with the LC50 of 0.046 mg/L against the third-instar S. furgiperda larve after 48 h treatment. All these results indicate that DSPE-EB nanoparticles can serve as an insecticide carrier with lower environmental impact, sustained release property, and effective control of pests.

Protocol for evaluating CD8+ T cell-mediated immunity in latently SHIV-infected rhesus macaques with HIV fusion-inhibitory lipopeptide monotherapy.

Strong cellular immunity contributes to the control of HIV infection. Here, we describe a step-by-step protocol to assess the simian immunodeficiency virus (SIV)-specific CD8+ T cell responses by quantifying the degranulation, cytokine and chemokine production from SHIVSF162P3-infected rhesus macaques with an HIV fusion-inhibitory lipopeptide (LP-98) monotherapy. We also present the steps for adoptive transfer of an anti-CD8 antibody into a stable virologic control (SVC) group of LP-98-treated monkeys, confirming a direct role of CD8+ T cells in SVC macaques. For complete details on the use and execution of this protocol, please refer to Xue et al. (2022).

SARS-CoV-2 fusion-inhibitory lipopeptides maintain high potency against divergent variants of concern including Omicron.

The emergence of SARS-CoV-2 Omicron and other variants of concern (VOCs) has brought huge challenges to control the COVID-19 pandemic, calling for urgent development of effective vaccines and therapeutic drugs. In this study, we focused on characterizing the impacts of divergent VOCs on the antiviral activity of lipopeptide-based fusion inhibitors that we previously developed. First, we found that pseudoviruses bearing the S proteins of five VOCs (Alpha, Beta, Gamma, Delta, and Omicron) and one variant of interest (Lambda) exhibited greatly decreased infectivity relative to the wild-type (WT) strain or single D614G mutant, especially the Omicron pseudovirus. Differently, the most of variants exhibited an S protein with significantly enhanced cell fusion activity, whereas the S protein of Omicron still mediated decreased cell-cell fusion. Next, we verified that two lipopeptide-based fusion inhibitors, IPB02V3 and IPB24, maintained the highly potent activities in inhibiting various S proteins-driven cell fusion and pseudovirus infection. Surprisingly, both IPB02V3 and IPB24 lipopeptides displayed greatly increased potencies against the infection of authentic Omicron strain relative to the WT virus. The results suggest that Omicron variant evolves with a reduced cell fusion capacity and is more sensitive to the inhibition of fusion-inhibitory lipopeptides; thus, IPB02V3 and IPB24 can be further developed as potent, broad-spectrum antivirals for combating Omicron and the potential future outbreak of other emerging variants.

Self-Reported Walking Pace and Risk of Cardiovascular Diseases: A Two-Sample Mendelian Randomization Study.

Background: In observational studies, the self-reported walking pace has been associated with the risk of cardiovascular diseases (CVD). However, whether those associations indicate causal links remains unclear. We performed two-sample Mendelian randomization (MR) analyses to evaluate the causal effect of walking pace on several CVD outcomes, including atrial fibrillation (AF), heart failure (HF), any stroke, ischemic stroke (IS), and IS subtypes. Methods: Genetic variants associated with self-reported walking pace were selected as instrumental variables (IVs) from the latest genome-wide association studies (GWAS). Summary-level data for outcomes were obtained from the corresponding GWAS and the FinnGen consortium. The random-effects inverse variance weighted (IVW) method was used as the main MR analysis, supplemented by replication analyses using data from the FinnGen. To explore the effect of pleiotropy due to adiposity-related traits, we further conducted MR analyses by excluding the adiposity-related IVs and regression-based multivariable MR adjusting for body mass index (BMI). Results: The MR results indicated significant inverse associations of self-reported walking pace with risks of AF [odds ratio (OR), 0.577; 95% confidence interval (CI), 0.442, 0.755; p = 5.87 × 10-5], HF (OR, 0.307; 95% CI, 0.229, 0.413; p = 5.31 × 10-15), any stroke (OR, 0.540; 95% CI, 0.388, 0.752; p = 2.63 × 10-4) and IS (OR, 0.604; 95% CI, 0.427, 0.853; p = 0.004) and suggestive inverse association of self-reported walking pace with cardioembolic stroke (CES) (OR, 0.492; 95% CI, 0.259, 0.934; p = 0.030). Similar results were replicated in the FinnGen consortium and persisted in the meta-analysis. However, there was no causality between walking pace and large artery stroke (OR, 0.676; 95% CI, 0.319, 1.434; p = 0.308) or small vessel stroke (OR, 0.603; 95% CI, 0.270, 1.349; p = 0.218). When excluding adiposity-related IVs and adjusting for BMI, the associations for HF and any stroke did not change substantially, whereas the associations for AF, IS, and CES were weakened. Conclusion: Our findings suggested that genetically predicted increasing walking pace exerted beneficial effects on AF, HF, any stroke, IS, and CES. Adiposity might partially mediate the effect of walking pace on AF, IS, and CES.

In Vitro Selection and Characterization of HIV-1 Variants with Increased Resistance to LP-40, Enfuvirtide-Based Lipopeptide Inhibitor.

In our previous work, we replaced the TRM (tryptophan-rich motif) of T20 (Enfuvirtide) with fatty acid (C16) to obtain the novel lipopeptide LP-40, and LP-40 displayed enhanced antiviral activity. In this study, we investigated whether the C16 modification could enhance the high-resistance barrier of the inhibitor LP-40. To address this question, we performed an in vitro simultaneous screening of HIV-1NL4-3 resistance to T20 and LP-40. The mechanism of drug resistance for HIV-1 Env was further studied using the expression and processing of the Env glycoprotein, the effect of the Env mutation on the entry and fusion ability of the virus, and an analysis of changes to the gp41 core structure. The results indicate that the LP-40 activity is enhanced and that it has a high resistance barrier. In a detailed analysis of the resistance sites, we found that mutations in L33S conferred a stronger resistance, except for the well-recognized mutations in amino acids 36-45 of gp41 NHR, which reduced the inhibitory activity of the CHR-derived peptides. The compensatory mutation of eight amino acids in the CHR region (NDQEEDYN) plays an important role in drug resistance. LP-40 and T20 have similar resistance mutation sites, and we speculate that the same resistance profile may arise if LP-40 is used in a clinical setting.