Latest research: inactivated vaccine is effective, recombinant adenovirus vector covid-19 vaccine is ineffective!
A new study shows that all animals vaccinated with recombinant adenovirus vectors were infected, and that the inactivated vaccine provided immune protection.
The recombinant adenovirus vector covid-19 vaccine was ineffective
As for the immune protection effect of covid-19 vaccine, a new study shows that all animals vaccinated with recombinant adenovirus vector vaccine are infected, and the inactivated vaccine has immune protection effect.
The results of the study, conducted by the virology laboratory at the national institute of allergy and infectious diseases, the national institutes of health and the jenner institute at the university of Oxford, are published in the May 13 preprint edition of BioRxiv.
The study focused on recombinant adenovirus vector vaccines and inactivated vaccines.Rhesus monkeys vaccinated with recombinant adenovirus vectors were infected with novel coronavirus, the researchers found.It can be seen that the recombinant adenovirus vector vaccine does not provide immunity to the virus attack and has no protective effect.
In stark contrast, another experiment was conducted at the same time.The inactivated vaccine, developed by sinovac biotech, was used by the researchers and showed a clear protective effect.Moreover, the titer of neutralizing antibody in the serum of inoculated animals was high, indicating that the vaccine was highly protective.
For the protection and safety of the inactivated vaccine, qinchuan team of Peking union medical college also published a paper on May 6 in the online Science.The study developed a purified inactivated novel coronavirus candidate vaccine that induces novel coronavirus specific neutralizing antibodies in mice, rats, and non-human primates.These antibodies effectively neutralized 10 representative novel coronavirus strains, indicating a potential for a broader neutralization of novel coronavirus strains in global circulation.
Notably, U.S. biomedical company Moderna extended premarket gains to 20 percent after it announced that its vaccine for covid-19, mrna-1273, is safe and well tolerated, with the final phase of vaccine trials expected to begin in July.
Chinese research teams have also made new breakthroughs
What is encouraging is that Chinese research teams have also made significant discoveries in the prevention and treatment of covid-19.
A Chinese research team has discovered two human monoclonal antibodies that block novel coronavirus infection and are expected to be used in the development of anti-coronavirus drugs and vaccines, according to a paper published online in the us journal science, xinhua reported Thursday.
Capital medical university of China, institute of microbiology, Chinese academy of sciences, tianjin institute of industrial biotechnology, Chinese academy of sciences, shenzhen third people’s hospital and other institutions were involved in the study.Four human monoclonal antibodies were isolated from peripheral blood monocytes of a covid-19 patient.Experiments showed that the four antibodies against novel coronavirus have the ability to neutralize.Among them, two antibodies named B38 and H4 block the binding domain of novel coronavirus spikes protein and its receptor “angiotensin-converting enzyme 2 (ACE2)”.
Several previous studies that revealed the mechanism of novel coronavirus infection indicated that the virus was infected mainly by binding its surface spike protein receptor domain to ACE2 on human cells.Experiments showed that B38 and H4 recognized different epitopes of receptor binding domains respectively, and mouse experiments confirmed that these two antibodies could reduce the amount of virus infecting the lungs of mice, showing a therapeutic effect.The two antibodies can also be used in combination to more effectively inhibit viral infection.
The team further elucidated the complex structure of the novel coronavirus spike protein receptor binding region with B38, revealing the molecular mechanism by which B38 blocks viral infection.
The latest research shows that the two antibodies screened have the potential to be further developed into drugs to treat novel coronavirus infections and provide the basis for vaccine design, the researchers said.At present, the two antibodies have been transformed into products in relevant companies and are expected to be used in clinical treatment of patients with covid-19 in the future.