The outbreak of the novel coronavirus disease quickly spread all over China and to more than 20 other countries. Although the virus (SARS-Cov-2) nucleic acid RT-PCR test has become the standard method for diagnosis of SARS-CoV-2 infection, these real-time PCR test kits have many limitations. In addition, high false negative rates were reported. There is an urgent need for an accurate and rapid test method to quickly identify large number of infected patients and asymptomatic carriers to prevent virus transmission and assure timely treatment of patients.We have developed a rapid and simple point-of-care lateral flow immunoassay which can detect IgM and IgG antibodies simultaneously against SARS-CoV-2 virus in human blood within 15 minutes which can detect patients at different infection stages. With this test kit, we carried out clinical studies to validate its clinical efficacy uses. The clinical detection sensitivity and specificity of this test were measured using blood samples collected from 397 PCR confirmed COVID-19 patients and 128 negative patients at 8 different clinical sites. The overall testing sensitivity was 88.66% and specificity was 90.63%. In addition, we evaluated clinical diagnosis results obtained from different types of venous and fingerstick blood samples. The results indicated great detection consistency among samples from fingerstick blood, serum and plasma of venous blood. The IgM-IgG combined assay has better utility and sensitivity compared with a single IgM or IgG test. It can be used for the rapid screening of SARS-CoV-2 carriers, symptomatic or asymptomatic, in hospitals, clinics, and test laboratories.

A DNA vaccine against the hepatitis B virus (HBV), enhanced by IL-2/IFN-γ fusion protein expression from a plasmid construct and mediated by in vivo electroporation, was evaluated in a total of 39 HBeAg-positive patients with chronic hepatitis B (CHB). The six of 39 patients with a serum alanine aminotransferase (ALT) value of 1-2 times upper limit of normal (ULN) were assigned to the open-label arm (Group01) receiving vaccine monotherapy; the remaining 33 patients with an ALT of more than two times ULN were enroled to the randomized and controlled arm (Group02) receiving lamivudine (LAM) monotherapy (LAM+placebo) or combined therapy (LAM+DNA vaccine) in 1:2 ratio. In Group01, a significant elevation of HBV-specific IFN-γ-secreting T-cell counts in comparison with baseline was observed. In Group02, the proportion of patients with HBV DNA suppression was higher with LAM+DNA vaccine than with LAM monotherapy at each visit time point after the final injection of DNA vaccine at week 36, revealing a significant difference between the two groups (P = 0.03) at week 60. The incidence of dual-site mutations of rtM204/I/S+rtL180M was significantly lower (P = 0.03) with an identified lower virological breakthrough (VBT) rate (P = 0.03) in patients receiving LAM+DNA vaccine than LAM monotherapy, accompanied with a significant higher positive T-cell response rate in patients receiving LAM+DNA vaccine (P = 0.03). In conclusion, this study provides evidence that HBV DNA vaccination is safe and immunologically effective, and that the HBV-specific T-cell responses induced by DNA vaccination under LAM chemotherapy showed a correlation with the suppression of viral replication in patients with CHB.

BackgroundAlthough the Newcastle disease virus (NDV) inactivated vaccines and attenuated live vaccines have been used to prevent and control Newcastle disease (ND) for years, there are some disadvantages. Recently, newly developed DNA vaccines have the potential to overcome these disadvantages. The low delivery efficiency, however, hindered the application of DNA vaccines for ND in practice.Methodology/Principal FindingsThe eukaryotic expression plasmid pVAX1-F (o) DNA that expressed the F gene of NDV encapsulated in PLGA nanoparticles (pFNDV-PLGA-NPs) were prepared by a double emulsion-solvent evaporation method and optimal preparation conditions of the pFNDV-PLGA-NPs were determined. Under the optimal conditions, the pFNDV-PLGA-NPs were produced in good morphology and had high stability with a mean diameter of 433.5±7.5 nm, with encapsulation efficiency of 91.8±0.3% and a Zeta potential of +2.7 mV. Release assay in vitro showed that the fusion gene plasmid DNA could be sustainably released from the pFNDV-PLGA-NPs up to 93.14% of the total amount. Cell transfection test indicated that the vaccine expressed and maintained its bioactivity. Immunization results showed that better immune responses of SPF chickens immunized with the pFNDV-PLGA-NPs were induced compared to the chickens immunized with the DNA vaccine alone. In addition, the safety of mucosal immunity delivery system of the pFNDV-PLGA-NPs was also tested in an in vitro cytotoxicity assay.Conclusions/SignificanceThe pFNDV-PLGA-NPs could induce stronger cellular, humoral, and mucosal immune responses and reached the sustained release effect. These results laid a foundation for further development of vaccines and drugs in PLGA nanoparticles.

Objective: We conducted a meta-analysis of randomized controlled trials to explore whether vitamin D supplementation is beneficial for symptom improvement in children with autism spectrum disorder. Methods: We systematically searched the PubMed database, EMBASE, Cochrane Library, Web of Science, Sino-Med, Wanfang Data, and China National Knowledge Infrastructure mainly up to September 2019. Using a fixed effects model, we calculated the standard mean difference with 95% confidence interval. Furthermore, we analyzed baseline serum 25-hydroxyvitamin D levels and outcome scores including the Social Responsiveness Scale and Child Autism Rating Scale scores after vitamin D supplementation. Results: There was no significant difference in baseline serum 25-hydroxyvitamin D levels among 203 children included from three studies in the meta-analysis. After vitamin D supplementation, the outcome scores in the experimental group were dramatically elevated compared with those in the control group (p = 0.03). Conclusion: Vitamin D supplementation improves the typical symptoms of autism spectrum disorder, as indicated by reduced Social Responsiveness Scale and Child Autism Rating Scale scores; thus, it is beneficial for children with autism spectrum disorder.

No abstract