'if a vaccine elicits an immune response that misses the target cells, the result could potentially be worse than if no vaccine was given.
"One of the problems with corona vaccines in the past has been that when the immune response does cross over to where the virus-infected cells are it actually increases the pathology rather than reducing it," Professor Frazer said.
"So that immunisation with SARS corona vaccine caused, in animals, inflammation in the lungs which wouldn't otherwise have been there if the vaccine hadn't been given."
[...] vaccine was tested with SARS in 2003 and resulted in reinfected lab monkeys having a nasty immune response, which is why many groups working on a vaccine for Sars-CoV-2 are going for a very specific antibody response.
Professor Frazer said the narrow, targeted approach is fine, unless you pick the wrong specific antigen — the substance that stimulates an immune response which antibodies bind to — in which case you could end up with the same problem.'
https://www.abc.net....NjIMOuFacFsJ9xI
Moderna:
'These initial results are based on tests of the low and medium doses. The only adverse effect at those doses was redness and soreness in one patient’s arm where the shot was given.
But at the highest dose, three patients had fever, muscle pains and headaches, Dr. Zaks said, adding that the symptoms went away after a day.
But the high dose is being eliminated from future studies, not so much because of the side effects, but because the lower doses appeared to work so well that the high dose is not needed.
[...] Moderna uses genetic material — messenger RNA — to make vaccines, and the company has nine others in various stages of development, including several for viruses that cause respiratory illnesses. But no vaccine made with this technology has yet reached the market.'
https://www.nytimes....hY6-kwq0eGbjcaU