- Game on.

(both laughing) Today, Arlo and I are searching for a hero.

- [Arlo] A molecule that is changing modern medicine and may help end the COVID-19 pandemic.

- [Arlo And Caitlin In Unison] Antibodies.

- Wow.

Those miracle molecules.

This is a journey full of surprises.

When this baby comes, we're going back into quarantine Requiring our very own blood... (Arlo groans) - [Arlo] Sweat... - [Caitlin] Arlo's a little squeamish.

- [Arlo] And... Definitely tears.

- Definitely tears.

- Oh yeah.

Every night.

- There are tears.

- [Duane] Right.

Well, we got your results.

- [Caitlin] Expect the unexpected folks.

- (laughs) You want to use both hands?

(light suspenseful music) It was the moment we had been waiting for for over a year.

Is it all right, I just want to film - [Nurse] Of course it is!

- [Caitlin] That wonderful, maybe mildly anticlimactic moment, when we finally got our jabs.

- [Arlo] That's it.

- Wow!

(laughs) - [Arlo] And a few weeks later, passports to freedom, followed by a swift triumphant end to the pandemic.

(fireworks cracking) Or so we thought.

But that moment of bliss did get us wondering.

- How do vaccines create these seemingly miraculous molecules that fight COVID and other diseases?

- [Arlo] How do antibodies work in our bodies?

- [Caitlin] How long do they stick around and how much do they protect us from COVID variants?

- And, most importantly, can I get through this episode without passing out?

Oh Jesus!

Woohee!

To find out more, we decided to talk to a molecular biologist, science communicator, and internet sensation, ♪ Body, antibody bodies ♪ Raven, the science maven.

♪ Antibodies ♪ ♪ IgM, IgA, IgM, IgE ♪ ♪ Antibody-ody-ody-ody-odies ♪ - Hey there Raven.

- Hey.

(laughs) - This is so cool.

What you do is so awesome.

- Aw thank you.

Are you ready for your mind to be blown?

- Oh yes.

♪ The category biology ♪ ♪ Lesson on immunology ♪ ♪ A lil microbiology ♪ ♪ This is the terminology ♪ - Okay, antibodies are also molecules, but they're complex.

They are linked together in different rings and chains and loops and... - Squigglies?

- Squigglies, But they're still molecules.

They're just more complex.

- [Arlo] At the most basic level, antibodies are Y shaped proteins.

The arms of the Y have what is called a variable region, meaning that the molecular structure here varies from one antibody to the next.

- There's like 10 billion different kinds of antibodies.

So what changes is the antibody's ability to bind or not bind to specific molecules or foreign invaders.

- Huh.

And that is key to how anybody's give us some immunity.

When they bind to an invader, they can do three things.

First, they can help block an invader, by making it harder for it to enter and infect cells.

Second, they can mark an invader for destruction by the immune system.

And third, they can signal our body to make more of that kind of antibody, so that our immune system can attack more invaders like it.

- [Caitlin] So, exactly how do we get antibodies by getting a COVID vaccine?

- The beauty of vaccines, is that it takes instructions to build a response without the actual infection.

- [Caitlin] Our body basically learns how to make the necessary antibodies using the instructions provided by the vaccine.

- In general, it's taking a piece of the pathogen and putting that in our bodies, so that our immune system can see it.

And if our immune system can see it, and if it takes the time to build the antibodies, then our immune response can develop and basically be ready to be able to handle the real thing.

- [Caitlin] Duane Wesemann is an immunology specialist, now studying antibody responses to COVID-19 and that's what brought us to his lab.

- We're collecting blood every month to try and identify what the immune response to these vaccines look like.

How long do they last and does their quality over time change?

(equipment hisses) - [Arlo] Are you kidding me?

- [Duane] That's cool, right?

- [Arlo] That's the best sound ever.

(scientist laughs) I'm going to have to re-sample that.

- [Caitlin] To learn how our immune systems reacted to the vaccine and how long that protection lasts, we donated some blood to the cause.

(Arlo groans in disgust) What's so gross about that?

It's beautiful blood.

- [Technician] You all right?

- Filled with tasty antibodies.

Arlo's afraid he's going to faint.

This is for chemistry though.

- Yeah.

Chemistry.

- [Technician] You're fine though?

You're fine?

- I'm fine.

I'm fine.

- We're going to give you a lollipop when we're done.

(laughs) - I want to cookie.

- [Caitlin] Once Duane's lab has our blood sample, first, they separate out our blood into its different components.

- [Caitlin] Whoa, that's really neat!

- [Duane] Isn't that beautiful?

So we take the blood and we process it such that we end up with these layers.

So we have this red blood cell layer, that's at the very bottom.

And then we have this other layer on top, and that's where the secreted antibodies are.

- [Caitlin] Once they have those antibodies, they can put a small amount on plates.

- [Duane] A lot of biology is transferring coalesced fluids from one plate to another.

- [Caitlin] And test to see if they bind with viral protein.

- So basically the more yellow you see, the more antibodies that are in there that are specific for the virus.

- [Caitlin] In other words, Duane can see how well the vaccine created an antibody response, but antibodies are not the full story when it comes to our immune response.

Going back to our separated blood sample, there is another component that is crucial.

- We have this thin disc, this cloudy middle layer right here.

And this is where the white blood cells are.

The B cells, the T-cells.

- [Caitlin] B-cells and T-cells.

B cells are our antibody factories.

T-cells play an important role in helping our body recognize and destroy invaders.

Certain B-cells and T-cells, called memory cells, will carry the chemical memory of the initial immune response and allow our body to make new antibodies to the virus in the future.

Including, importantly, antibodies that also work against variants of the virus.

- It's a remarkable way to collaborate with our immune system to teach it something that we know about.

We figured out some infectious threat, we develop a vaccine, and it has been hugely successful.

These are Arlo cells.

- [Arlo] Are they?

- They are.

- [Caitlin] Arlo and I will continue to return to Duane's lab to provide new blood samples month after month.

This will allow Duane to study how our vaccine antibody response changes over time.

And this kind of data is of particular concern to me because not too long ago...

I'm really excited.

I did not expect this.

I'm pregnant.

I have no idea what to do next, pregnant in a pandemic, but... As excited as I was, it also threw my vaccination plans into complete confusion because initial COVID vaccine clinical trials did not include pregnant and lactating individuals.

There were no data available to show how the vaccine might affect people like me or our babies.

And as someone who truly values data, this initially made me nervous.

Like I was never vaccine hesitant until I entered this population, you know, somewhat unexpectedly.

Like, hey pandemic, baby.

(laughs) - Yeah, everyone we saw was having questions.

- [Caitlin] I sat down with Katie Gray, a high-risk obstetrician and clinical geneticist who told me something reassuring about the data that has, since come out.

- There haven't been any adverse effects reported in babies to date.

So, so far there's no safety signals.

- [Caitlin] In August, 2021.

The CDC released a statement and new data confirming the vaccine is safe for pregnant people.

But the reason I ultimately opted to get my jab back in April, when there was still incomplete data, was because of a study that Katie co-authored, and it all gets back to antibodies.

- We found that all of the patients who had maternal antibodies, so antibodies in mom's blood, they all passed the antibodies to the cord blood, which was very reassuring.

- Wow!

- And they all have passed it to the breast milk too, in the lactating patients.

- So I get a vaccine, I generate these antibodies, I give some of them to the, to my baby.

- Yes, yes.

- So the baby gets some protection?

- I mean, that's what we would assume based on what we see.

- [Caitlin] I can't state enough how, for me, this was the clincher.

If I get a vaccine, I'm not only protecting myself, with no known side effects to the baby, but I'm possibly giving the baby some protection too, but there is a major caveat with this reassuring news.

- What's happening is the antibodies pass from mom, through the placenta, to the baby's blood.

But those other components of the immune system that get stimulated in an adult patient who is vaccinated.

That's not what's happening in the infant.

So while we would presume there's some benefit from the maternal vaccination, we shouldn't treat an infant born to a vaccinated mom as though they were vaccinated.

We should still exercise the same caution that we should for any other unvaccinated child, which is a tricky thing for all parents to navigate right now.

- So it's like, it's something, but we don't know how much of something it is.

- That's right.

- [Caitlin] This small something was still a huge relief.

knowing my baby would be born with some antibodies against the virus, the hero molecule protecting both me and my child.

But, as we've learned before, moments of bliss are sometimes short-lived.

Okay.

So first we want to understand these results, both as they apply to us, but more importantly, how they're reflecting maybe a larger trend that we're seeing in the population.

- Right.

What we see for your sample, is that there's an induction after vaccination, it peaks.

And then it starts to decline afterwards.

And this is what we see with everyone else, the antibody levels decline over time.

- [Caitlin] It turns out, the antibody response we get from vaccination does not last forever.

This was not welcome news.

My own antibody count has dipped to almost pre-vaccine levels in just four months.

I have to say, it was kind of a bummer to see these results.

- Tell me about that.

What's the bummer?

- I don't know.

When we started, you know, making this episode and we were thinking about talking about antibodies, they were like going to be the hero.

They were going to end the pandemic, you know.

Early in the summer, everybody was super excited.

- And then all of a sudden... (laughs) Oh my god!

- And then for me, like thinking about the variants and having a kid and what I'm passing to the kid, seeing the antibodies drop, I felt...scared.

Like, oh my gosh, how am I going to protect my child?

- You know that...Man, I feel for you about that.

We were surprised.

This pandemic has been kind of a thing that's been teaching us at every turn.

Yeah.

It's a learning process.

I mean, in a way, ignorance is bliss, but... (laughs) - Oh, I know.

- But my personal view, is that that shouldn't be a barrier from learning the information.

It's like, you know, we're going to learn things that might cause some anxiety.

And we don't quite know what the influence of that thing we learn will have on our future.

But there is a benefit from knowing, you know what I'm saying?

That doesn't mean our challenges are over.

- Yeah.

And that's it, that's a really good point because now at least I have the information to make the best decisions.

And, like, that's what science is, is like looking at reality and making the best decisions you can after you talk to the scientists who can help you interpret the data.

(laughs) And though the data shows that our antibodies are waning, that's not the full story.

- The immune system is a very complex, wonderful system.

And yes, for this particular case, the antibody levels go down.

But there's other aspects of the immune system that still remember what happened, that might respond a little better.

- Our old pals, memory B and T-cells, they still stick around after our antibody levels start to decrease, ready and waiting to launch a new immune response.

So even though our antibodies are dropping, we still presumably have our immune system trained, a little bit, to be able to respond more quickly.

- That's absolutely correct.

So it's best to have both because they're non-redundant roles.

You know, the antibodies are there immediately, they help protect, but you still have this backup memory cell system that can act as a safety net and be able to produce antibodies more quickly.

- [Caitlin] Scientists are still studying the memory cell response to COVID-19.

So there are still some questions, regarding how comprehensive this protection is, and how long it lasts.

And memory cell response, still isn't the kind of robust protection we get immediately after vaccination.

That's why booster shots are now being offered for some individuals.

And possibly down the line, for all of us.

- I would argue that antibodies are still the hero.

(Caitlin laughs) There are just not enough of them around.

We need more heroes.

- [Caitlin] The data in this episode surprised us.

And for one protective mother hormone fueled day, I really believed that ignorance would have been bliss, but knowledge is also power.

And now I can make informed decisions that will protect me and my family.

- [Arlo] And with some of the world's best scientists working on understanding this virus and developing new vaccine strategies, with the help of our heroic antibodies, the fight is not over yet.

- [Caitlin] Until then, there's always those little moments of bliss.

I'm really excited I'm having a baby.

(laughs) I'll take him for lots of walks outside.

- Is that a changing table?

- Yep.

I'm days away from my due date, so I don't even have a desk anymore.

(laughs) This is a stuffed seal that somebody got me.

- (laughs) Yes.

- Because I was so in love with the seals from Antarctica, which is when I decided I wanted to have kids.

(Arlo laughs) I can name this one Arlo, if you'd like?

- Okay, that works for me.

- Okay.

Bye.

it's pretty important for you to stay healthy, but there is so much medical misinformation out there but there is so much medical misinformation out there that it can be pretty hard to separate fact from fiction.

Vitals.

PBS's brand new health and wellness show is here to help.

Their first episode is all about the COVID vaccine in kids.

They'll unpack why a kid's vaccine is taking so long, the latest breakthroughs, and answer all your questions with science, research, and facts.

Check out Vitals in the link in the description and tell them Out of Our Element sent you.