Okay, I admit it: I have the luxury of a 2 hour bike ride, which is just enough time to listen to a TWiV episode end to end, and most people cannot or will not do that and I understand.
But this latest episode #642 is a gem.
Everything you ever wanted to know about how vaccines can and are being developed, the problems which have to be overcome, how vaccines are shown to be safe and to be effective.
Brianne Barker, that stellar immunologist from Drew University in New Jersey, explains the nuts and bolts of which cells are involved and Rich Condit leads her interrogation asking just the question which floats up before my eyes after each of her sentences and so she then goes to explain the why.
Vince Raccaniello and Alan Dove and Dickson Despommier chime in to elucidate anything Rich missed.
For those of you who will not schedule in, here forthwith is my humble attempt to offer a synopsis. But really, nobody can adequately do justice to this lovely panel.
Here is the link:
https://www.microbe.tv/twiv/twiv-642/
Here's the nub:
1/ Vaccines come as different models: There are SUVs and sports cars. There are trains and planes. They all transport but they do it in different ways. Most vaccines under development depend on going after the spike protein, which is putting a lot of eggs in one basket. All have risks.
2/ A paper detailing the mRNA vaccine from Moderna is discussed.
The vaccine works by going after the spike protein on the virus which attaches it to the cell it wants to attack and take over.
There is a lot of talk about changing an amino acid in nucleic acids which the Phantom cannot recall well enough. He will listen a second time.
This is a "phase one study" which is meant to test the safety of the vaccine and to take the first step in assessing potential efficacy: measuring antibody levels.
3/ When any vaccine is given into a deltoid muscle, it attracts B cells which make antibodies. There are different sorts of antibodies, including neutralizing antibodies and its various type of antibody levels which researchers look for to infer how much protection a patient receiving the vaccine might get from the vaccine. But antibodies are not protection; they are an indicator of something which happens which might confer protection. It's like seeing the troops armed on the border and what kind of weapons they carry, but you don't know how well they will fight until you attack, until you test.
4/ Other things then happen, after the antibodies get made. T cells get programmed, alerted, set up to swing into action. There are at least two types of T cells which swing into action and Type1 may protect the patient by identifying the infected cells while Type 2 may do that but may release a kind of cytokine which actually makes the patient worse. So far, the Moderna vaccine seems to program the right type of T cell.
This is important because most patients die not from the virus but because of the immune system's explosive reaction to the virus--a sort of Dr. Strangelove scenario, a doomsday machine.
5/ Weeks to months after the antibody levels rise, they fall.
This has caused a Twitter storm because people assumed falling antibodies were a bad thing. Like withdrawing troops from the border--you'd be unprotected.
But, as Brianne Barker points out, falling antibody levels are not necessarily a bad thing with respect to protection. You don't want to have millions of cells and tons of antibody after every infection with every virus which never regress "or you'd be nothing but one big lymph node." What you want is a well trained army which can be mobilized quickly at the next attack.
6/ The current trial is encouraging and now they are recruiting 30,000 patients for the next phase of the study, which is done by vaccinating people and then sending them out into communities where they will likely be exposed and tracking how many get sick and how many appeared to be infected. You do not "challenge" them by giving them virus because its considered unethical to give a study subject something which might kill them or which may leave them without their fingers or legs (an outcome seen after clotting complications in some patients.)
Listen to this and you re enter planet Earth, where science and inquiry thrive.
It restores your faith in humanity.
But this latest episode #642 is a gem.
Everything you ever wanted to know about how vaccines can and are being developed, the problems which have to be overcome, how vaccines are shown to be safe and to be effective.
Brianne Barker, that stellar immunologist from Drew University in New Jersey, explains the nuts and bolts of which cells are involved and Rich Condit leads her interrogation asking just the question which floats up before my eyes after each of her sentences and so she then goes to explain the why.
Vince Raccaniello and Alan Dove and Dickson Despommier chime in to elucidate anything Rich missed.
For those of you who will not schedule in, here forthwith is my humble attempt to offer a synopsis. But really, nobody can adequately do justice to this lovely panel.
Here is the link:
https://www.microbe.tv/twiv/twiv-642/
Here's the nub:
1/ Vaccines come as different models: There are SUVs and sports cars. There are trains and planes. They all transport but they do it in different ways. Most vaccines under development depend on going after the spike protein, which is putting a lot of eggs in one basket. All have risks.
2/ A paper detailing the mRNA vaccine from Moderna is discussed.
The vaccine works by going after the spike protein on the virus which attaches it to the cell it wants to attack and take over.
There is a lot of talk about changing an amino acid in nucleic acids which the Phantom cannot recall well enough. He will listen a second time.
This is a "phase one study" which is meant to test the safety of the vaccine and to take the first step in assessing potential efficacy: measuring antibody levels.
3/ When any vaccine is given into a deltoid muscle, it attracts B cells which make antibodies. There are different sorts of antibodies, including neutralizing antibodies and its various type of antibody levels which researchers look for to infer how much protection a patient receiving the vaccine might get from the vaccine. But antibodies are not protection; they are an indicator of something which happens which might confer protection. It's like seeing the troops armed on the border and what kind of weapons they carry, but you don't know how well they will fight until you attack, until you test.
 |
| Angela Merkel, a Scientist |
4/ Other things then happen, after the antibodies get made. T cells get programmed, alerted, set up to swing into action. There are at least two types of T cells which swing into action and Type1 may protect the patient by identifying the infected cells while Type 2 may do that but may release a kind of cytokine which actually makes the patient worse. So far, the Moderna vaccine seems to program the right type of T cell.
This is important because most patients die not from the virus but because of the immune system's explosive reaction to the virus--a sort of Dr. Strangelove scenario, a doomsday machine.
 |
| American Response |
5/ Weeks to months after the antibody levels rise, they fall.
This has caused a Twitter storm because people assumed falling antibodies were a bad thing. Like withdrawing troops from the border--you'd be unprotected.
But, as Brianne Barker points out, falling antibody levels are not necessarily a bad thing with respect to protection. You don't want to have millions of cells and tons of antibody after every infection with every virus which never regress "or you'd be nothing but one big lymph node." What you want is a well trained army which can be mobilized quickly at the next attack.
 |
| American Leadership |
6/ The current trial is encouraging and now they are recruiting 30,000 patients for the next phase of the study, which is done by vaccinating people and then sending them out into communities where they will likely be exposed and tracking how many get sick and how many appeared to be infected. You do not "challenge" them by giving them virus because its considered unethical to give a study subject something which might kill them or which may leave them without their fingers or legs (an outcome seen after clotting complications in some patients.)
Listen to this and you re enter planet Earth, where science and inquiry thrive.
It restores your faith in humanity.
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