with the first research doses of vaccine Moderna
dubbed “mRNA-1273,” the NIH researchers
immunized dozens of mice. Days later, they
started collecting blood samples to check if the
mice were producing antibodies against that all-
important spike protein. One early test: Mix the
mouse samples with thawed spike protein and
various color-eliciting trackers, and if antibodies
are present, they bind to the protein and glow.
Corbett says the work couldn’t have moved so
quickly had it not been for years of behind-the-
scenes lab testing of a possible MERS vaccine
that works the same way.
“I think about it a lot, how many of the little
experimental questions we did not have to
belabor” this time around, she said. When she saw
the first promising mouse tests, “I felt like there
was a beginning of all of this coming full circle.”
INOVIO’S APPROACH
Inovio’s approach is similar -- again using genetic
code, in this case packaged inside a piece of
synthetic DNA that acts as the vaccine. One
advantage Broderick cites for a DNA approach
is that unlike many types of vaccines, it may not
need refrigeration.
A MERS vaccine that Inovio designed the same
way passed initial safety studies in people, paving
the way for testing the new COVID-19 vaccine
candidate. Inovio is doing similar animal testing
to look for presumably protective antibodies.
While it gets ready for human safety tests,
Inovio also is prepping for another piece of
evidence — what’s called a challenge study.
Vaccinated animals will be put in a special
high-containment lab and exposed to the new
coronavirus to see if they get infected or not.