Preparation and epitope mapping of monoclonal antibodies against African swine fever virus p22 protein.

African swine fever (ASF), caused by the African swine fever virus (ASFV), is now widespread in many countries and severely affects the commercial rearing of swine. Rapid and early diagnosis is crucial for the prevention of ASF. ASFV mature virions comprise the inner envelope protein, p22, making it an excellent candidate for the serological diagnosis and surveillance of ASF. In this study, the prokaryotic-expressed p22 recombinant protein was prepared and purified for immunization in mice. Four monoclonal antibodies (mAbs) were identified using hybridoma cell fusion, clone purification, and immunological assays. The epitopes of mAbs 14G1 and 22D8 were further defined by alanine-scanning mutagenesis. Our results showed that amino acids C39, K40, V41, D42, C45, G48, E49, and C51 directly bound to 14G1, while the key amino acid epitope for 22D8 included K161, Y162, G163, D165, H166, I167, and I168. Homologous and structural analysis revealed that these sites were highly conserved across Asian and European ASFV strains, and the amino acids identified were located on the surface of p22. Thus, our study contributes to a better understanding of the antigenicity of the ASFV p22 protein, and the results could facilitate the prevention and control of ASF.

Evaluation of a novel disposable esophagogastroduodenoscopy system in emergency, bedside, and intraoperative settings: Pilot study (with videos).

OBJECTIVES: The disposable esophagogastroduodenoscopy (EGD) system is a novel endoscopic device which is highly portable and is designed to eliminate the risk of cross-infection caused by reusable EGD. This study aimed to investigate the feasibility and safety of disposable EGD in emergency, bedside, and intraoperative settings. METHODS: This was a prospective, single-center, noncomparative study. Disposable EGD was used for emergency, bedside, and intraoperative endoscopies in 30 patients. The primary end-point was the technical success rate of the disposable EGD. Secondary end-points included technical performance indicators including clinical operability, image quality score, procedure time, the incidence of device malfunction and/or failure, and the incidence of adverse events. RESULTS: A total of 30 patients underwent diagnosis and/or treatment with disposable EGD. Therapeutic EGD was performed on 13/30 patients, including hemostasis (n = 3), foreign body retrieval (n = 6), nasoenteric tube placement (n = 3), and percutaneous endoscopic gastrostomy (n = 1). The technical success rate was 100%: all procedures and indicated interventions were completed without changing to a conventional upper endoscope. The mean image quality score obtained immediately after procedure completion was 3.72 ± 0.56. The mean (± SD) procedure time was 7.4 (± 7.6) min. There were no device malfunctions or failures, device-related adverse events, or overall adverse events. CONCLUSION: The disposable EGD may be a feasible alternative to the traditional EGD in emergency, bedside, and intraoperative settings. Preliminary data show that it is a safe and effective tool for diagnosis and treatment in emergency and bedside upper gastrointestinal cases. TRIAL REGISTRATION: Chinese Clinical Trial Registry (Trial ID: ChiCTR2100051452, https://www.chictr.org.cn/showprojen.aspx?proj=134284).

Standing-type magnetically guided capsule endoscopy versus gastroscopy for gastric examination: multicenter blinded comparative trial.

AIM: To compare feasibility and safety after gastrointestinal checkup by standing-type magnetically controlled capsule endoscopy (SMCE) and conventional gastroscopy. METHODS: This was a prospective multicenter, blinded study that compared SMCE with gastroscopy in patients from April 2018 to July 2018. All patients first underwent SMCE and then subsequently had gastroscopy with i.v. anesthesia. We calculated the compliance rates of gastric lesion detection by SMCE using gastroscopy as the standard. Capsule retention rate, incidence of adverse events, and patient satisfaction were documented throughout the study. RESULTS: One hundred and sixty-one patients who completed SMCE and gastroscopy were included in the analysis. Positive compliance rate among SMCE and gastroscopy was 92.0% (95% CI: 80.77%-97.78%). Negative compliance rate was 95.5% (89.80%, 98.52%). Moreover, overall compliance rate was 94.41% (89.65%, 97.41%). Sixty-four pathological outcomes were identified. Of these 64 outcomes, 50 were detected by both procedures. The gastroscopy method neglected seven findings (such as five erosions, one polyp, and one ulcer). Furthermore, SMCE also overlooked seven lesions (i.e. one erosion, two polyps, one atrophy, and three submucosal tumors). Capsule retention or related adverse events were not reported. CONCLUSION: Standing-type magnetically controlled capsule endoscopy provides equivalent agreement with gastroscopy and may be useful for screening of gastric illnesses without any anesthesia.