Effect of electroacupuncture of "Jiaji" (EX-B2) on NOD-like receptor protein 3 mediated pyroptosis in spinal cord tissue of rats with acute spinal cord injury. / å¤¹è„Šç”µé’ˆå¯¹æ€¥æ€§è„Šé«“æŸä¼¤å¤§é¼ è„Šé«“ç»„ç»‡NODæ ·å—ä½“çƒ­è›‹ç™½ç»“æž„åŸŸç›¸å ³è›‹ç™½3介导的细胞焦亡的影响.

OBJECTIVES: To observe the effect of electroacupuncture (EA) stimulation of "Jiaji"(EX-B2) on motor function, histomorphology, and expression of NOD-like receptor protein 3 (NLRP3) and N-terminal domain of gasdermin D (GSDMD-N) in the spinal cord tissue of rats with spinal cord injury (SCI), so as to explore its mechanism underlying improvement of SCI. METHODS: Forty eight female SD rats were randomly divided into sham surgery (sham), SCI model (model), EA, and NLRP3 agonist (monosodium urate, MSU) combined with Jiaji EA (MSU+EA) groups, with 12 rats in each group which were further divided into 3 d and 7 d subgroups, with 6 rats at each time point. Two EA groups received EA stimulation of EX-B2 with a frequency of 100 Hz, electrical current of 1-2 mA for 30 min, once a day for 3 or 7 days. After 5 min, 6 h, and 24 h of modeling, rats of the MSU+EA group received intraperitoneal injection of MSU (200 µg/kg, 200 µg/mL) . The motor function was evaluated using Basso-Beattie-Bresnahan (BBB) scale, the morphological structure of rat spinal cord tissue was observed by H.E. staining. The expression of pyroptosis related factors NLRP3, cleaved Caspase-1 and GSDMD-N of the spinal cord was observed by using immunohistochemistry and Western blot separately, the expression and localization of Iba-1 and GSDMD-N in the spinal cord tissue were observed using immunofluorescence double staining method. RESULTS: Compared with the sham group, the BBB scores after modeling and on day 3 and 7 were decreased (P<0.05), while the average OD values (immunoactivity) and expression levels of NLRP3, cleaved Caspase-1 and GSDMD-N proteins, and the immunofluorescence intensity of Iba-1/GSDMD-N (co-expression) of the spinal cord tissues on day 3 and 7 were significantly increased in the model group (P<0.05). In comparison with the model group, the BBB scores on day 3 and 7 were obviously increased (P<0.05), while the immunoactivity and expression levels of NLRP3, cleaved Caspase-1 and GSDMD proteins, and the immunofluorescence intensity of Iba-1/GSDMD-N on day 3 and 7 significantly down-regulated in the EA group (P<0.05) but not in the MSU+EA group (P>0.05), suggesting an elimination of the effects of EA after administration of NLRP3 agonist (MSU). H.E. staining showed obvious bleeding area in the spinal cord tissue, loose tissue and inflammatory cell infiltration on day 3 after modeling, and basic absorption of the bleeding, loose tissue, obvious vacuolar changes of the white matter area, loss and contraction of neurons with infiltration of a large number of inflammatory cells, which was milder in the EA group but not in the MSU+EA group. CONCLUSIONS: EA of EX-B2 can improve the motor function of SCI rats, which may be related to its functions in inhibiting pyroptosis of microglia mediated by NLRP3/Caspase-1 signaling pathway.

Dual Branch Multi-Level Semantic Learning for Few-Shot Segmentation.

Few-shot semantic segmentation aims to segment novel-class objects in a query image with only a few annotated examples in support images. Although progress has been made recently by combining prototype-based metric learning, existing methods still face two main challenges. First, various intra-class objects between the support and query images or semantically similar inter-class objects can seriously harm the segmentation performance due to their poor feature representations. Second, the latent novel classes are treated as the background in most methods, leading to a learning bias, whereby these novel classes are difficult to correctly segment as foreground. To solve these problems, we propose a dual-branch learning method. The class-specific branch encourages representations of objects to be more distinguishable by increasing the inter-class distance while decreasing the intra-class distance. In parallel, the class-agnostic branch focuses on minimizing the foreground class feature distribution and maximizing the features between the foreground and background, thus increasing the generalizability to novel classes in the test stage. Furthermore, to obtain more representative features, pixel-level and prototype-level semantic learning are both involved in the two branches. The method is evaluated on PASCAL- 5i 1 -shot, PASCAL- 5i 5 -shot, COCO- 20i 1 -shot, and COCO- 20i 5 -shot, and extensive experiments show that our approach is effective for few-shot semantic segmentation despite its simplicity.

Photodynamic therapy for refractory erosive oral lichen planus: a case series study.

Oral lichen planus is a chronic inflammatory disease that occurs on the oral mucosa and is an oral potentially malignant disease. Treatment of oral lichen planus aims to promote healing of the erosion, relieve pain, reduce recurrence of the erosion, and prevent canceration. Corticosteroids are the first line of treatment for oral lichen planus. Refractory oral lichen planus is a clinical classification of oral lichen planus that has not responded to corticosteroid treatment for more than 2 months. Topical 5-aminolevulinic acid-mediated photodynamic therapy is an innovative and effective treatment for potentially malignant oral diseases and has been reported as an alternative treatment to conventional therapies for oral lichen planus. On this basis, we report 3 cases of refractory erosive oral lichen planus in which persistent erosive lesions healed after topical application of 5-aminolevulinic acid-mediated photodynamic therapy without any adverse effects or any signs of recurrence. Topical 5-aminolevulinic acid-mediated photodynamic therapy will become an effective clinical treatment for refractory erosive oral lichen planus.

A potential broad-spectrum neutralizing antibody against Betacoronavirus.

Three pandemics caused by human Betacoronavirus had broken out in the past two decades. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was one of the novel epidemic strains which caused the third pandemic, coronavirus disease 2019 (COVID-19), a global public health crisis. So far, more than millions of people have been infected. Considering the public health and economic impact of Betacoronavirus pandemic, drugs with broad-spectrum activity against these coronaviruses are urgently needed. In this study, two monoclonal antibodies targeting SARS-CoV-2 spike protein receptor-binding domain (RBD) with good neutralizing activity were used to construct a novel immunoglobulin-like bispecific antibody BI31. The neutralizing effect of BI31 against the pseudovirus and the authentic virus is better than that of its parent antibodies alone and in combination. What surprised us most was that the newly constructed bispecific antibody also had the neutralizing activity against SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV) that the parent antibodies did not have. These suggested that the BI31 can not only be developed as a therapeutic drug against COVID-19 but it could also become a broad-spectrum therapeutic antibody against Betacoronavirus.

A human bispecific antibody neutralizes botulinum neurotoxin serotype A.

Botulinum neurotoxin (BoNT) shows high lethality and toxicity, marking it as an important biological threat. The only effective post-exposure therapy is botulinum antitoxin; however, such products have great potential for improvement. To prevent or treat BoNT, monoclonal antibodies (mAbs) are promising agents. Herein, we aimed to construct a bispecific antibody (termed LUZ-A1-A3) based on the anti-BoNT/A human monoclonal antibodies (HMAb) A1 and A3. LUZ-A1-A3 binds to the Hc and L-HN domains of BoNT/A, displaying potent neutralization activity against BoNT/A (124 × higher than that of HMAb A1 or HMAb A3 alone and 15 × higher than that of the A1 + A3 combination). LUZ-A1-A3 provided effective protection against BoNT/A in an in vivo mouse model. Mice were protected from infection with 500 × LD50 of BoNT/A by LUZ-A1-A3 from up to 7 days before intraperitoneal administration of BoNT/A. We also demonstrated the effective therapeutic capacity of LUZ-A1-A3 against BoNT/A in a mouse model. LUZ-A1-A3 (5 µg/mouse) neutralized 20 × LD50 of BoNT/A at 3 h after intraperitoneal BoNT/A administration and complete neutralized 20 × LD50 of BoNT/A at 0.5 h after intraperitoneal BoNT/A administration. Thus, LUZ-A1-A3 is a promising agent for the pre-exposure prophylaxis and post-exposure treatment of BoNT/A.

Diagnostic value of contrast-enhanced ultrasonography in the preoperative evaluation of lymph node metastasis in papillary thyroid carcinoma: a single-center retrospective study.

BACKGROUND: Contrast-enhanced ultrasound (CEUS) has been recently used for the assessment of cervical lymph node metastasis (LNM) to guide surgical operation in patients with papillary thyroid carcinoma (PTC). However, the specificity and sensitivity of CEUS reported from previous studies are not consistent. The objective of this study was to evaluate the diagnostic value of CEUS for the metastasis of cervical lymph nodes in PTC patients based on data from one regional central hospital. METHODS: The diagnostic value of CEUS in preoperative LNM of PTC patients was concluded by comparing the results of CEUS on lymph node status with postoperative pathology examination. In addition, this study conducted hierarchical analysis of PTC patients to explore whether tumor size, different lymph node regions, and Hashimoto's thyroiditis influence the assessment of CEUS. RESULTS: This research study ultimately enrolled 965 PTC patients, including 266 males and 699 females with a mean age of 42.27 ± 11.34 years. A total of 527 patients were considered clinical-node negative, and 438 were clinical-node positive before surgery. The specificity, sensitivity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of CEUS in the assessment of LNM in PTC patients were 56.00%, 71.00%, 57.06%, 69.76% and 62.59%, respectively. For central and lateral lymph nodes, the accuracy of CEUS in PTC patients was 49.43% and 54.30%, respectively. In addition, it was shown that the accuracy of CEUS in PTC patients with Hashimoto's thyroiditis (HT) slightly decreased to 58.44%, and the accuracy of CEUS in PTC patients with non-HT in turn increased to 64.17%. The accuracy of CEUS in non-papillary thyroid microcarcinoma (PTMC) and PTMC patients was 65.68% and 61.24%, respectively. The accuracy of CEUS in predicting central LNM was significantly different between PTC patients with or without HT (P < 0.001) in this study but not for lateral lymph nodes (P = 0.114). CONCLUSION: The accuracy of CEUS in the assessment of LNM in PTC is not consistently satisfactory, especially for central lymph nodes, small tumor diameters, or patients with HT. More diagnostic technologies for abnormal lymph nodes should be considered in PTC patients.

Tetanus toxin and botulinum neurotoxin-derived fusion molecules are effective bivalent vaccines.

Tetanus toxin (TeNT) and botulinum neurotoxins (BoNTs) are neuroprotein toxins, with the latter being the most toxic known protein. They are structurally similar and contain three functional domains: an N-terminal catalytic domain (light chain), an internal heavy-chain translocation domain (HN domain), and a C-terminal heavy chain receptor binding domain (Hc domain or RBD). In this study, fusion functional domain molecules consisting of the TeNT RBD (THc) and the BoNT/A RBD (AHc) (i.e., THc-Linker-AHc and AHc-Linker-THc) were designed, prepared, and identified. The interaction of each Hc domain and the ganglioside receptor (GT1b) or the receptor synaptic vesicle glycoprotein 2 (SV2) was explored in vitro. Their immune response characteristics and protective efficacy were investigated in animal models. The recombinant THc-linker-AHc and AHc-linker-THc proteins with the binding activity had the correct size and structure, thus representing novel subunit vaccines. THc-linker-AHc and AHc-linker-THc induced high levels of specific neutralizing antibodies, and showed strong immune protective efficacy against both toxins. The high antibody titers against the two novel fusion domain molecules and against individual THc and AHc suggested that the THc and AHc domains, as antigens in the fusion functional domain molecules, do not interact with each other and retain their full key epitopes responsible for inducing neutralizing antibodies. Thus, the recombinant THc-linker-AHc and AHc-linker-THc molecules are strong and effective bivalent biotoxin vaccines, protecting against two biotoxins simultaneously. Our experimental design will be valuable to develop recombinant double-RBD fusion molecules as potent bivalent subunit vaccines against bio-toxins. KEY POINTS: • Double-RBD fusion molecules from two toxins had the correct structure and activity. • THc-linker-AHc and AHc-linker-THc efficiently protected against both biotoxins. • Such bivalent biotoxin vaccines based on the RBD are a valuable experimental design.

The evil companion of OSCC: Candida albicans.

OBJECTIVE: Microbial dysbiosis and microbiome-induced inflammation may play a role in the etiopathogenesis of oral squamous cell carcinoma (OSCC). Candida albicans (C. albicans) is the most prevalent opportunistic pathogenic fungus in the oral cavity, and Candida infection is considered as one of its high-risk factors. Although oral microbiota-host interactions are closely associated with the development of OSCC, the interrelationship between fungi and OSCC is poorly understood compared to that between bacteria and viruses. RESULTS: We accumulated knowledge of the evidence, pathogenic factors, and possible multiple mechanisms by which C. albicans promotes malignant transformation of OSCC, focusing on the induction of epithelial damage, production of carcinogens, and regulation of the tumor microenvironment. In addition, we highlight the latest treatment strategies for Candida infection. CONCLUSION: This review provides a new perspective on the interrelationship between C. albicans and OSCC and contributes to the establishment of a systematic and reliable clinical treatment system for OSCC patients with C. albicans infection.

[Evaluation of the clinical effect of acupuncture in treatment of neck pain in cervical spondylosis based on propensity score matching].

OBJECTIVE: To observe the clinical effect and safety of acupuncture in treatment of neck pain due to cervical spondylosis. METHODS: According to the patients' preference and acceptance for the interventions of neck pain induced by cervical spondylosis, an acupuncture group (221 cases) and a non-acupuncture group (251 cases) were divided. After the control of confounding factors with propensity score matching, 218 cases were included in either acupuncture group or non-acupuncture group. In the acupuncture group, acupuncture was applied to Dazhui (GV 14), Baihui (GV 20), ashi points, bilateral neck-Jiaji (EX-B 2), Fengchi (GB 20), Houxi (SI 3), Shenmai (BL 62), etc. The treatment was given once daily, one course of intervention was composed of 5 treatments and 3 courses were included. In the non-acupuncture group, the oral administration of imrecoxib tablets and cobalt tablets was prescribed for 2 weeks. Before and after treatment, the scores of Northwick Park questionnaire (NPQ) and the simplified McGill pain questionnaire (SF-MPQ) were observed, and the safety was assessed in patients of the two groups. RESULTS: After treatment completion, the scores of NPQ and SF-MPQ were all reduced when compared with those before treatment in each group (P<0.001), and the scores of NPQ and SF-MPQ in the acupuncture group were lower than those of the non-acupuncture group (P<0.001). The incidence of adverse reactions was 6.0% (13/218) in the acupuncture group and was 10.1% (22/218) in the non-acupuncture group, without statistical significance in comparison (P>0.05). CONCLUSION: Acupuncture is effective and safe in the relief of neck pain and the improvement of comprehensive quality of life in the patients with cervical spondylosis.

[Research progress of acupuncture-moxibustion in treatment of spinal cord injury through mediating inflammatory reaction].

Inflammatory reaction after spinal cord injury (SCI) is the main obstacle to the recovery of neural function. In the occurrence and development of SCI, the complex regulatory mechanisms are involved in inflammatory reaction, including the activation of inflammatory cells (e.g.macrophages and microglia), and the release of cytokines (e.g. tumor necrosis factor, interleukin and chemokines). Acupuncture-moxibustion is significantly effective in clinical treatment of SCI, and its mechanism is related to adjusting the function of inflammatory cells after SCI, modulating the expression of cytokines and the activation of NLRP3 inflammatory bodies, as well as the expression of high mobility group protein B1 and calcitonin gene related peptide. This article summarizes the research progress of mechanism of inflammatory reaction after SCI and the effects of acupuncture-moxibustion intervention in recent years so that the new ideas can be provided to clarify the pathogenesis of SCI and the effect of acupuncture-moxibustion intervention.

Predictive nomogram for central lymph node metastasis in papillary thyroid microcarcinoma based on pathological and ultrasound features.

Background: Central lymph node metastases (CLNM) in papillary thyroid microcarcinoma (PTMC) are common, but management through prophylactic central lymph node dissection (pCLND) remains controversial. In this study, the independent predictors of CLNM in PTMC were retrospectively studied based on ultrasound and pathological data, and we aim to establish the prediction model to predict CLNM in PTMC. Methods: This study included a total of 1,506 patients who underwent thyroid surgery for PTMC at the First Affiliated Hospital of Chongqing Medical University from 2015 to 2018. Ultrasound and clinicopathological features were summarized and analyzed. Univariate and multivariate analyses were performed to determine the risk factors associated with CLNM. The prediction model is established and verified according to the multivariate analysis results. The Kaplan-Meier curve was used to evaluate the effect of CLNM on survival. Results: The CLNM rate was 44.5% (670/1,506). Multivariate analysis showed that men, younger age, smaller diameter, ETE, microcalcification, without Hashimoto's thyroiditis, and multifocal were independent risk predictors of CLNM. Nomogram has a good discriminative ability (C-index: 0.755 in the validation group), and the calibration effect is good. In the DCA curve, the CLNM prediction model performed better net benefit given any high-risk thresholds. The median follow-up time was 30 months (12-59 months), 116 cases were lost, and the follow-up rate was 92.8% (1,506/1,622). Of the 1,506 patients included, 12 (0.8%) experienced recurrence. Conclusion: The likelihood of CLNM can be objectively quantified before surgery by using this reliable and accurate nomogram that combines preoperative ultrasound with clinicopathological features. Clinicians can use this nomogram to assess central lymph node status in patients with PTMC and consider prophylactic CND in patients with high scores.

Comparative effectiveness of moxibustion and acupuncture for the management of osteoarthritis knee: A systematic review and meta-analysis.

Background: Moxibustion, a traditional Chinese medicine approach, stimulates blood circulation by burning wormwood at acupuncture points and is frequently used in conjunction with acupuncture for managing knee osteoarthritis. This review aims to compare the effectiveness of moxibustion and acupuncture in the management of knee osteoarthritis. Methods: Our team conducted a comprehensive search across several databases: PubMed Central, EMBASE, MEDLINE, the Chinese Biomedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI), and the Cochrane Library, covering the timeframe from January 1964 up until April 2022. We implemented a meta-analysis, utilizing a random-effects model, and we've presented the pooled standardized mean difference (SMD) and risk ratio (RR) inclusive of the 95% confidence intervals (CIs), in accordance with the nature of the outcome. Results: 21 studies were included, of which, half were identified as having high risk of bias. The pooled SMD for the pain score was found to be -0.53 (95% CI: -0.91 to -0.15). In-depth analysis focusing on the kind of moxibustion indicated that fire needle moxibustion was more effective in pain reduction (SMD = -0.56; 95% CI: -1.10 to -0.01) compared to alternative moxibustion methods (SMD = -0.47; 95% CI: -0.80 to -0.13). The pooled RR for the success rate in treatment was 1.39 (95% CI: 1.19 to 1.62). Subgroup analysis demonstrated that fire needle moxibustion reported a superior success rate (RR = 1.43; 95% CI: 1.19 to 1.72) in comparison to other types of moxibustion (RR = 1.33; 95% CI: 1.02 to 1.74). Conclusion: Moxibustion, specifically fire needle moxibustion, demonstrated superior effectiveness in managing knee osteoarthritis compared to acupuncture.

Lactational retrorsine exposure changes maternal milk components and disturbs metabolism homeostasis of offspring rats.

Pyrrolizidine alkaloids (PAs) are a type of plant-derived environmental toxins, which pose a health hazard to human and livestock via contaminating soil, water, plants and food. In this study, we aimed to investigate the effect of lactational retrorsine (RTS, a typical toxic PA) exposure on breastmilk components and glucose-lipid metabolism of offspring rats. Dams were intragastrically administered with 5 mg/(kg·d) RTS during lactation. After metabolomic analyses, 114 differential constituents were identified in breastmilk between control and RTS groups, featured by reduction of lipids and lipid-like molecules, while presence of abundant RTS and its derivative in RTS-exposed milk. RTS exposure induced liver injury in pups, but the leakage of transaminases in serum recovered in their adulthood. Serum glucose levels were lower in pups but higher in male adult offspring from RTS group. RTS exposure also induced hypertriglyceridemia, hepatic steatosis and decreased glycogen content in both pups and adult offspring. Additionally, suppression of PPARα-FGF21 axis persisted in offspring liver after RTS exposure. These data indicated that inhibition of PPARα-FGF21 axis induced by milk deficient in lipid contents, together with hepatotoxic injury caused by RTS in breastmilk, may disrupt glucose and lipid metabolism of pups, and the persistent suppression of PPARα-FGF21 axis may program metabolic disorder of glucose and lipid in adult offspring.

Anti-inflammatory effect and antihepatoma mechanism of carrimycin.

BACKGROUND: New drugs are urgently needed for the treatment of liver cancer, a feat that could be feasibly accomplished by finding new therapeutic purposes for marketed drugs to save time and costs. As a new class of national anti-infective drugs, carrimycin (CAM) has strong activity against gram-positive bacteria and no cross resistance with similar drugs. Studies have shown that the components of CAM have anticancer effects. AIM: To obtain a deeper understanding of CAM, its distribution, metabolism and anti-inflammatory effects were assessed in the organs of mice, and its mechanism of action against liver cancer was predicted by a network pharmacology method. METHODS: In this paper, the content of isovaleryl spiramycin III was used as an index to assess the distribution and metabolism of CAM and its effect on inflammatory factors in various mouse tissues and organs. Reverse molecular docking technology was utilized to determine the target of CAM, identify each target protein based on disease type, and establish a target protein-disease type network to ascertain the effect of CAM in liver cancer. Then, the key action targets of CAM in liver cancer were screened by a network pharmacology method, and the core targets were verified by molecular docking and visual analyses. RESULTS: The maximum CAM concentration was reached in the liver, kidney, lung and spleen 2.5 h after intragastric administration. In the intestine, the maximum drug concentration was reached 0.5 h after administration. In addition, CAM significantly reduced the interleukin-4 (IL-4) levels in the lung and kidney and especially the liver and spleen; moreover, CAM significantly reduced the IL-1ß levels in the spleen, liver, and kidney and particularly the small intestine and lung. CAM is predicted to regulate related pathways by acting on many targets, such as albumin, estrogen receptor 1, epidermal growth factor receptor and caspase 3, to treat cancer, inflammation and other diseases. CONCLUSION: We determined that CAM inhibited inflammation. We also predicted the complex multitargeted effects of CAM that involve multiple pathways and the diversity of these effects in the treatment of liver cancer, which provides a basis and direction for further clinical research.

A humanized anti-human adenovirus 55 monoclonal antibody with good neutralization ability.

Background: Human adenovirus type 55 (HAdV55) has a re-emerged as pathogen causing an acute respiratory disease presenting as a severe lower respiratory illness that can cause death. To date, there is no HAdV55 vaccine or treatment available for general use. Methods: Herein, a monoclonal antibody specific for HAdV55, mAb 9-8, was isolated from an scFv-phage display library derived from mice immunized with the purified inactived-HAdV55 virions. By using ELISA and a virus micro-neutralization assay, we evaluated the binding and neutralizing activity of mAb 9-8 following humanization. Western blotting analysis and antigen-antibody molecular docking analysis were used to identify the antigenic epitopes that the humanized monoclonal antibody 9-8-h2 recognized. After that, their thermal stability was determined. Results: MAb 9-8 showed potent neutralization activity against HAdV55. After humanization, the humanized neutralizing monoclonal antibody (9-8-h2) was identified to neutralize HAdV55 infection with an IC50 of 0.6050 nM. The mAb 9-8-h2 recognized HAdV55 and HAdV7 virus particles, but not HAdV4 particles. Although mAb 9-8-h2 could recognize HAdV7, it could not neutralize HAdV7. Furthermore, mAb 9-8-h2 recognized a conformational neutralization epitope of the fiber protein and the crucial amino acid residues (Arg 288, Asp 157, and Asn 200) were identified. MAb 9-8-h2 also showed favorable general physicochemical properties, including good thermostability and pH stability. Conclusions: Overall, mAb 9-8-h2 might be a promising molecule for the prevention and treatment of HAdV55.

Humanization and characterization of a murine monoclonal neutralizing antibody against human adenovirus 7.

Human adenovirus type 7 (HAdV7) is commonly associated with febrile acute respiratory disease (ARD) outbreaks. We have reported that 10G12, a mouse monoclonal antibody (mAb) specifically recognizing and neutralizing HAdV7, is a promising candidate for humanization. In this study, we engineered the six variants of 10G12 with increased degree of humanization and investigated their biological activity. The humanized monoclonal antibody (mAb) 10G12-M2 was shown to retain the parental antibody's high binding affinity, specificity and potent efficacy of viral suppression. The mAb 10G12-M2 recognized a conformational neutralization epitope of the hexon protein. Complex structure-based molecular docking simulation showed that the hexon protein formed several interactions with 10G12-M2, including hydrogen bonds and salt bridges interaction. Physicochemical properties analysis of 10G12-M2 demonstrated that it is stable and desirable lead candidate. In general, 10G12-M2 had excellent biological activity after humanization combined with the potential for use in prophylactic or therapeutic applications against HAdV7.

Characterization of a novel tetravalent botulism antitoxin based on receptor-binding domain of BoNTs.

Botulinum neurotoxin (BoNTs; serotypes A, B, E, and F) cause botulism disease in humans, which could be effectively treated using antitoxins. Herein, we established a novel receptor-binding domain (RBD)-based antitoxin using recombinant C terminal heavy chain (Hc) domains of BoNTs as immunogens. Immunization of horses with these recombinant Hc domains allowed the purification and digestion of IgGs from hyper-immune sera to produce high-quality and high-efficiency monovalent botulism antitoxin F(ab')2 against each BoNT (M-BATs). However, these M-BATs could not bind or neutralize other serotypes of BoNTs, and that there were no cross-protective effects among these M-BATs. This suggested the need to prepare tetravalent antitoxins to neutralize the four BoNTs simultaneously. Thus, these M-BATs were formulated into a novel tetravalent botulism antitoxin (T-BAT), in which a 10-ml volume contained 10000 IU of BoNT/A and 5000 IU of BoNT/B, BoNT/E, and BoNT/F antitoxins. The novel antitoxin preparation could prevent and treat the four mixed botulinum neurotoxins simultaneously in vivo, representing strong efficacy in an animal poisoning model. Moreover, these antibodies in T-BAT could bind the RBD, whereas conventional antitoxins based on inactivated toxins mainly bind the light chain or heavy chain translocation domain (HN) and weakly bind the important RBD in current experimental conditions. The high levels of RBD-specific novel antitoxins can efficiently bind the RBD and neutralize natural or recombinant toxins containing this RBD. The findings of the present study experimentally support the use of RBD-specific antitoxins to treat BoNT serotype A, B, E, and F-mediated botulism. This study demonstrated the concept of developing potent novel multivalent antitoxins against all BoNTs or other toxins, using the RBD of these toxins as an alternative antigen to inactivated toxins. KEY POINTS: • Antitoxins based on the receptor-binding domains of botulinum neurotoxins were made. • Novel antitoxin binds RBD; traditional antitoxin mainly binds light chain or HN domain. • A tetravalent antitoxin could prevent and treat the four mixed neurotoxins in vivo.

Biological and Immunological Characterization of a Functional L-HN Derivative of Botulinum Neurotoxin Serotype F.

Botulinum neurotoxins (BoNTs) can cause nerve paralysis syndrome in mammals and other vertebrates. BoNTs are the most toxic biotoxins known and are classified as Class A biological warfare agents. BoNTs are mainly divided into seven serotypes A-G and new neurotoxins BoNT/H and BoNT/X, which have similar functions. BoNT proteins are 150 kDa polypeptide consisting of two chains and three domains: the light chain (L, catalytic domain, 50 kDa) and the heavy chain (H, 100 kDa), which can be divided into an N-terminal membrane translocation domain (HN, 50 kDa) and a C-terminal receptor binding domain (Hc, 50 kDa). In current study, we explored the immunoprotective efficacy of each functional molecule of BoNT/F and the biological characteristics of the light chain-heavy N-terminal domain (FL-HN). The two structure forms of FL-HN (i.e., FL-HN-SC: single chain FL-HN and FL-HN-DC: di-chain FL-HN) were developed and identified. FL-HN-SC could cleave the vesicle associated membrane protein 2 (VAMP2) substrate protein in vitro as FL-HN-DC or FL. While only FL-HN-DC had neurotoxicity and could enter neuro-2a cells to cleave VAMP2. Our results showed that the FL-HN-SC had a better immune protection effect than the Hc of BoNT/F (FHc), which indicated that L-HN-SC, as an antigen, provided the strongest protective effects against BoNT/F among all the tested functional molecules. Further in-depth research on the different molecular forms of FL-HN suggested that there were some important antibody epitopes at the L-HN junction of BoNT/F. Thus, FL-HN-SC could be used as a subunit vaccine to replace the FHc subunit vaccine and/or toxoid vaccine, and to develop antibody immune molecules targeting L and HN domains rather than the FHc domain. FL-HN-DC could be used as a new functional molecule to evaluate and explore the structure and activity of toxin molecules. Further exploration of the biological activity and molecular mechanism of the functional FL-HN or BoNT/F is warranted.

Accidental acquisition of a rescued Japanese encephalitis virus with unspliced introns in the viral genome when using an intron-based stabilization approach.

The intron-based stabilization approach is a very useful strategy for construction of stable flavivirus infectious clones. SA14-14-2 is a highly attenuated Japanese encephalitis (JE) live vaccine strain that has been widely used in China since 1989. To develop safe and effective recombinant vaccines with SA14-14-2 as a backbone vector, we constructed the DNA-based infectious clone pCMW-JEV of SA14-14-2 using the intron-based stabilization approach and acquired the rescued virus rDJEV, which retained the biological properties of the parental virus. Unexpectedly, a rescued virus strain with altered virulence, designated rHV-DJEV, was accidentally acquired in one of the transfection experiments. rHV-DJEV showed up to 105-fold increased neurovirulence compared with the SA14-14-2 parental strain. Genome sequencing showed that the inserted introns were still present in the genome of rHV-DJEV. Therefore, we think that the intron-based stabilization approach should be used with caution in vaccine development and direct iDNA immunization.