Evaluation of anti-spike glycoprotein antibody and neutralizing antibody response of different vaccine platforms. A protocol of systematic review and meta-analysis of COVID-19 vaccine clinical trial studies

BackgroundThe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in late 2019 and spread globally, prompting an international effort to accelerate development of a vaccine. SARS-CoV-2 transmit among the people fast and infected thousands of people daily around the world. Because of rapid transmission of SARS-CoV-2 among the people, there is an urgent need to prevent people from infection or hospitalization and control the disease. MethodsWe will search electronic databases such as PubMed, Web of Science, Cochrane (CENTRAL), Scopus, Google scholar, the key journals (vaccine and vaccines). Moreover, trial registry including clinicalTrials.gov, WHO ICTRP, and ISRCTN will be searched. We will only select all clinical trial studies in any phases of evaluation (i.e. phase I, II, II, IV). For anti-spike glycoprotein antibody (IgG) response and neutralizing antibody response, we will report Ratio of Geometric Mean (RoGM), Ratio of Mean (RoM) or standardized mean difference (SMD) depends on type of articles. DiscussionVarious vaccine platforms have been developed to increase the resistance to the SARS-CoV2 virus and reduce hospitalization and mortality rates. The comprehensive data gathering and analysis of results will guide scientists about the best available evidence. Moreover, the current study results may indicate which of the vaccine platforms are more effective and safe for COVID-19.

Biological properties the novel application of N-trimethyl chitosan nanospheres as a stabilizer and preservative in tetanus vaccine

Purpose@#Chitosan is a natural polymer that has excellent properties include biocompatibility, biodegradability, no cytotoxicity, high charge density, low cost, mucoadhesive, permeation enhancing (ability to cross tight junction), and immunomodulating ability that makes the spectrum of its applicability much broader. This study was conducted to investigate the stabilizing, preservative and immunogenicity properties of N-trimethyl chitosan nanospheres (N-TMCNS). @*Materials and Methods@#The tetanus toxoid (TT) was encapsulated into N-TMCNS and then characterized by scanning electron microscope, atomic force microscope, and dynamic light scattering. For stabilizer assay of N-TMCNS after storage of TT-N-TMCNS at different temperatures for 3 weeks, they were used for immunization of mice and different temperatures groups’ anti-TT-N-TMCNS production compared with other groups. Finally, the immunized mice were challenged with tetanus toxin. The preservation activity of TT-N-TMCNS against Escherichia coli was compared with thimerosal formulated TT. @*Results@#Our results revealed that heat-treated TT-N-TMCNS could induce higher titer of neutralizing immunoglobulin G in compared to TT vaccine and was able to protect the mice better than TT vaccine in challenge test. Furthermore, N-TMCNS as a preservative inhibited the growth of E. coli more effective than thimerosal. @*Conclusion@#Overall, the obtained results indicated that the N-TMCNS is one of the best stabilizer and preservative agent that can be used in the formulation of TT vaccine.

Crimean-Congo hemorrhagic fever from the immunopathogenesis, clinical, diagnostic, and therapeutic perspective: A scoping review

Crimean-Congo hemorrhagic fever virus (CCHFV) is responsible for widespread tick-borne zoonotic viral disease CCHF in African, Middle Eastern, Asian, and European countries. CCHFV can be spread to humans through tick bites or contact with infected animals or humans, and it often progresses from asymptomatic to severe/lethal illness, with fatality rates ranging from 10% to 40% in humans. Today, CCHF is growing into a significant public health concern due to its very high prevalence, severity of the condition, and lack of available vaccines and specific treatments. Recent research has been drawn towards a more accurate study of CCHFV characteristics, including the structure, genetic diversity, mechanisms involved in pathogenesis and immunopathogenesis, and clinical features. In addition, the use of animal models (mouse and non-human primates) and advanced diagnostic tools in recent years has resulted in a significant advance in CCHF related studies. In this context, we summarized the latest findings about CCHF research, its health complications, animal models, current diagnosis, vaccination, and CCHF treatments, and therapeutic strategies. Furthermore, we discussed existing deficiencies and problems in CCHFV analysis, as well as areas that still need to yield conclusive answers.