On Our Way to a Vaccine - Part 3

Today's blog is a follow-up to last week's second part blog about "On Our Way to a Vaccine," which is based upon an article in the New York Times Sunday Magazine. [ Entitled: "The Development of a Vaccine for COVID-19," June 14, 2020, Page 36-43, 56. ]

How Do We Test

Susan R. Weiss says, "With  COVID-19, there's currently a hamster model that looks like it works pretty well to mimic the disease and also some promising research with mice, ferrets and also nonhuman primates." The model has importance in terms of replicating mammalian sysmptoms.

Siddhartha Mukerjee worked on two separate studies regarding vaccine development: He said, "There are two key scientific questions related to animal vaccine development:"

1. If we are exposed to the virus and live, will we have lifelong immunity?
2. Which vaccines out of a number of suggested ones will be the ones to focus on (1)

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In the first study, nine monkies were infected with Sars-COVID-2 in the nose and lungs. All nine developed viral pneumonia, similar to the human version, except that the monkey version was less virulent and all the monkies survived.

Thirty-five days later the same monkies were exposed to the same virus, and all nine of the monkies were protected, with very low trace of the virus in their systems. (2)

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In the second study, Mukerjee develped a series of prototype vaccines. He said, "These were naked "DNA Vaccines,"  or ones without any delivery vehicles, as mentioned before. (3)   According to Mukerjee they were designed to see how the immune system works against a virus. Twenty-five monkies received various versions, and depending upon how six different spike genes were developed.  All were innoculated and six weeks later they were exposed to the virus and:

•    8 of the 25 had no virus detection
•  17 of the 25 had very low detection to the virus

Mukerjee said, "Most important, the level of antibodies induced by the vaccine correlated with the level of protection, and this biomarker may therefore be useful for monitoring vaccine studies moving forward." (4)

The most important part of these two studies is that the results  suggest that natural immunity and vaccine-induced immunity can exist in primates and that the amount of antibody may serve as a useful marker for vaccine effectiveness. (5)

_________________ To be continued  in Part 4    _______________________

Contributors for this Sunday Magazine NYTimes article were:

Dan Barouch, Director, Center for Virology and Vaccine, Beth Israel Hospital, Boston, MA.

Margaret (Peggy) Hamburg, Foreign Secretary, National Academy of Medicine; previous Commissioner of the F.D.A. from 2009 to 2015.

Siddhartha Mukerjee, Associate Professor of Medicine, Columbia University.

Susan R. Weiss, Professor and Vicechairwoman of the Department of Microbiology at the University of Pennsylvania, and the co-director of the Penn Center for Research on Coronavirus and Other Emerging Pathogens.

George Yancopulos, Co-founder, President and Chief Scientific Officer of Regeneron.

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(1) "The Development of a Vaccine fro COVID-19," June 14, 2020, Page 40. 

(2)   Ibid.

(3)   Ibid.

(4)   Ibid.

(5)   Ibid.