14 ms·

Intranasal, but not intramuscular vaccination, elicited spike-specific respiratory mucosal IgA and residential T cell immune responses, in addition to systemic

Intranasal, but not intramuscular vaccination, elicited spike-specific respiratory mucosal IgA and residential T cell immune responses, in addition to systemic neutralizing antibodies and T cell immune responses against most Omicron subvariants. SARS-CoV-2 infection starts in the upper respiratory system, where the nasopharyngeal tract is at the forefront. To prevent viruses from attaching and replicating at the mucosal epithelium, effective mucosal immunity in the airway is critically important. Although only in mice, it does at least have a solid hypothesis for why they wish to do it this way.

jxramos 4y ago
I heard this criticism recently that injection site has little relation to the natural point of infection and if you overlap the two there could be some stronger synergies elicited by the location somehow. Also you don't risk the accidental intravenous delivery which can have terrible outcomes when the syringe isn't first aspirated to sample if you hit some open vasculature along the way.
- DoreenMichele 4y ago
  The entire reason the lungs are lined with mucus is to keep out invaders. So there's that.
  - jxramos 4y ago
    yah that's the rub, to expose to a natural infection site while also overcoming the defenses of that site but not so much that things spin out of control. Tricky gambit. But intranasal is like the pharynx and nasal passages and turbinates stuff, not all the way down in the lungs.
    - DoreenMichele 4y ago
      Those are all interconnected.
      - jxramos 4y ago
        yah but I think the lungs would connect more with the terminology of inhalation than intranasal. I think the language ties to different body parts, distinctions like show up in this random title I grabbed > Comparison of traditional intranasal and aerosol inhalation inoculation of mice with influenza A viruses https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5725743/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5725743/ I suppose an intranasal agent could accidentally get inhaled, but I think it's not meant to, it would probably elicit a choking reaction and not make it very deep into the lungs. Inhaled stuff is like smoke and nebulizer things.
        DoreenMichele 4y ago
        We have EENTs -- Eye, Ear, Nose, Throat doctors -- because you don't get to neatly divide up the body that way for your convenience. Just like the platypus exists because nature didn't ask humans how we wished to categorize animals before deciding nature was OK with an egg-laying mammal, even though most mammals don't lay eggs.
- andrekandre 4y ago
  > Also you don't risk the accidental intravenous delivery which can have terrible outcomes when the syringe isn't first aspirated to sample if you hit some open vasculature along the way. how often does this happen?
  - jxramos 4y ago
    I'm not sure if its ever been quantified anywhere. One way to sample it I guess is to aspirate all the time and see if any blood gets drawn up and start to aggregate some simple incidence rate on the number of occurrences one experiences over time and the total number of injections given. From what I heard that whole process fell out of favor to optimize for comfort and rapidity over the possible futzing with a syringe still embedded in the body.

jxramos 4y ago

I heard this criticism recently that injection site has little relation to the natural point of infection and if you overlap the two there could be some stronger synergies elicited by the location somehow. Also you don't risk the accidental intravenous delivery which can have terrible outcomes when the syringe isn't first aspirated to sample if you hit some open vasculature along the way.

DoreenMichele 4y ago
The entire reason the lungs are lined with mucus is to keep out invaders. So there's that.
- jxramos 4y ago
  yah that's the rub, to expose to a natural infection site while also overcoming the defenses of that site but not so much that things spin out of control. Tricky gambit. But intranasal is like the pharynx and nasal passages and turbinates stuff, not all the way down in the lungs.
  - DoreenMichele 4y ago
    Those are all interconnected.
    - jxramos 4y ago
      yah but I think the lungs would connect more with the terminology of inhalation than intranasal. I think the language ties to different body parts, distinctions like show up in this random title I grabbed > Comparison of traditional intranasal and aerosol inhalation inoculation of mice with influenza A viruses https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5725743/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5725743/ I suppose an intranasal agent could accidentally get inhaled, but I think it's not meant to, it would probably elicit a choking reaction and not make it very deep into the lungs. Inhaled stuff is like smoke and nebulizer things.
      - DoreenMichele 4y ago
        We have EENTs -- Eye, Ear, Nose, Throat doctors -- because you don't get to neatly divide up the body that way for your convenience. Just like the platypus exists because nature didn't ask humans how we wished to categorize animals before deciding nature was OK with an egg-laying mammal, even though most mammals don't lay eggs.
andrekandre 4y ago
> Also you don't risk the accidental intravenous delivery which can have terrible outcomes when the syringe isn't first aspirated to sample if you hit some open vasculature along the way. how often does this happen?
- jxramos 4y ago
  I'm not sure if its ever been quantified anywhere. One way to sample it I guess is to aspirate all the time and see if any blood gets drawn up and start to aggregate some simple incidence rate on the number of occurrences one experiences over time and the total number of injections given. From what I heard that whole process fell out of favor to optimize for comfort and rapidity over the possible futzing with a syringe still embedded in the body.