Video images capture the relentless spread of the COVID-19 virus for the first time in living animals and track infections as they move from the nose of mice to the lungs and other organs over a 6-day period. Researchers at Yale University and the University of Montreal.
The images document the deadly march of SARS-CoV-2, the virus responsible for COVID-19, while the introduction of antibodies collected from humans recovered from the virus can prevent or treat infection. Also shows.
However, studies have also shown that antibodies that lack the ability to mobilize killer immune system cells are less effective in combating infection.
the study, Published online on August 18th in pre-proof format The journal Immunity was all headed by Priti Kumar, Pradeep Uchil, Walther Mothes of Yale University School of Medicine, and Andrés Finzi of the University of Montreal.
“”For the first time, we were able to visualize the spread of SARS-CoV-2 in living animals in real time. And importantly, we were able to visualize where the antibody needed to be effective in stopping the progression of the infection. Professor of Infectious Diseases at Yale School of Medicine and co-author of the treatise.
In this study, co-authors Irfan Ullah, a postdoc at Yale University, and Jérémie Prévost, Montreal, used bioluminescent tagging and advanced microscopy to track the spread of the virus to the level of a single cell. .. In mice, the virus followed a path familiar to doctors treating human patients, with high viral load first appearing in the nasal cavity and then rapidly migrating to the lungs and eventually other organs. When the virus reached the brain, the mice eventually died.
Researchers then used human plasma recovered from COVID-19 to treat some infected mice. This stopped the spread of the virus even if it was administered within 3 days of infection. When these antibodies were given before the virus was infected, researchers found that they completely prevented the infection.
“”Live imaging virus spread reports can be used to quickly identify whether treatment works in 3-5 days. This is an important time-saving feature for developing countermeasures for current and future pandemics, “said research scientist Uchil. In the Mothes laboratory of the Faculty of Microbial Pathogenesis at Yale University.
However, researchers have found that not all antibodies work equally well. Antibodies have two main roles. Neutralizing antibodies bind to the virus and prevent it from entering the cell. Next, the second part of the antibody shows a function known as the “effector” function. This is needed to signal the immune system to attack and kill infected cells.
“”Antibodies are multifunctional molecules with several properties, “Finzi said. “This study shows that the ability to” seek help “from other cells of the immune system and the ability to eliminate infected cells are needed to provide optimal protection. “
Kumar added: “I thought that just neutralizing the virus could prevent the infection, but the antibody needs to be in the right place in the body in the right amount and at the right time. Without effector function, medium The harmony alone is not very effective. “
Other collaborators included Craig Wilen of Yale University, Mark Ladinsky and Pamela Bjorkman of the California Institute of Technology, Leonidas Stamatatos and Andrew McGuire of the Fred Hutchinson Cancer Research Center, and Marzena Pazgier of the Uniformed Services University of Health Sciences.
Video captures the deadly progression of the COVID-19 virus
Source link Video captures the deadly progression of the COVID-19 virus