Microchimerism: The Mother Inside You

You can say, you can also go far to say that our our cellular communities are nothing more than than just that communities of individuals that make up this whole. And in this episode of stuff Will in your mind, we're gonna throw another log onto that fire that illuminates the the multiple aspects of who we are. That's right. It is the chimera, which is this idea that comes from Greek mythology. We're talking about a fire breathing creature

that was part serpent, part lion, and part goat. And in many ways, when we talk about being host and and having some sort of micro biome in us, that perhaps gaming the way that we work physically and mentally, we are these kind of part line goat Chimera. Yeah. According to Homer, Um it just had the body of the gigantic goat, the hind parts of the serpent, the head of a lion, other depictions. You see, it is having head of all three. Really, it's kind of train

wreck of a monster. It's not it's not not the most elegant. Uh. It was said to be the progeny of two other monsters, um a kidney beautiful woman up top, serpent down below, and Typhon, which is a nebulous gigantic form composed of hundreds of dragons, heads and serpent, arms and legs, breathe fire and love. And it was created by Gaya after the defeat of the Titans to assail the forces of the gods. And in the Chimera had all these monsters siblings, including Cerebus, the Ninian Lion, the Hydra,

and the Sphinx. Is eventually slain by Bellerophon Astride the Pegasus, and in medieval already comes to symbolize the complex na nature of evil. Okay, and we we wanted to bring up the Chimera in both its mythological form and in the form of animals because we're going to get to it. But there's some really cool things going on on a celegular level that sort of brings into question who we are. We always bring this up, like, am I really me? Am I? Parts of me? Um? What is mean? What's this?

My brain and my body? Am I a brain? Body? Am I the me that I think I am? Or am I to me that exists under the surface of conscious thought? Well? Or am I the me that is really accumulation of actually other people in other people's cells? How could that be? Yes, we'll find out. But first let's talk about some naturally occurring chimeras. We're talking about slime, mold, and corals. Those are far less ominous than the fire

breathing kind, right and um. Chimeric can also refer to an animal that has two or more different sets of genetically distinct cells working together. So we have a couple of man made examples. One is a pig that researchers at the Mayo Clinic in Minnesota had created a pig with human blood pumping through its veins, and some of the cells merged together, creating pig human cell hybrid cells. Here.

So what we're talking about is this idea that you can have an experiment that could give scientists bet our understanding of how viral infections can pass from one animal to humans, like HIV. It's not just like, hey, let's cross a pig's blood with a humans blood and have some fun here, you know. It kind of sounds like it's a way to to create a ready source of human blood and then you just mark the pigs in when it's time for a transfusion. That would work too. Yeah,

it's kind of monstrous on all fronts. But I mean, but again, we get into this idea that we're dealing with, this initial idea that chimera as a monster, that any kind of form that involves bits of others is a hybrid, and it's weird and it's gross and probably against God's natural order. But it's we discussing here. Hybrids do occur within the natural limits of life, and in a sense, we are all chimeras. It's right, micro chimers, which we'll

talk about in a moment. But I wanted to bring up this particularly uh pure form of chimera in the form of humans. And uh, this became known because in a woman named Jane found out that she needed a kidney transplant. An amazing story, all right, So she has her son, she has three sons, and uh, they give some blood samples to see if she would be a

good match to be a kidney downer. Well what comes back is that, okay, um, what you know, miss Jane or whatever your full name is, because that's never actually told obviously for her privacy. But what comes back is, miss Jane, we want to tell you that you could not possibly be the biological mother of these two of your three sons, which to her is sort of like, what are you talking about? Because that it either means oh, I'm not who I think I am or the children

were swapped out in the hospital. You can just imagine the various scenarios that would roll around in your head and wrestle with each other when the doctors telling you that, yeah, and she's saying, no, I'm the biological mother these children. Trust me. I had them. They came out of my uterus. I have this memory of it. And they keep saying, well, are you sure you know? Maybe they were switched at birth? And it took the researchers two years to figure this out.

But Margot Crestfall, she was a daughter. She is a doctor at Beth Israel Deaconess Medical Center in Boston figured out that Jane is a chimera, a mixture of two individuals, and what we're talking about are non identical twin sisters who fused in the womb and grew into a single body. Yes, she dwight shrewded her twin. Well, it's it's almost crazier than that. It's like, it's not just like she be.

Those two people became one, you know. It's like it's like the fly Jeff Goldbloom in a telepod with a fly, and they emerged, the one being on the other end, essentially a chimera. And here we have in the telepod of the womb, these two individuals merged together and become a single organism, a single individual. Yes, so I mean she is She's technically a tetra game medic chimera, and that is a person whose body is made up from two genetically distinct lines of cells derived from a total

of four gamme eats, eggs, and sperm. So the cells from only one twin have come to dominate and Jane's blood, so the tissue used in the tissue typing in the test for her kidney. That's what we're talking about here. In her other tissues, including her ovaries, cells of both

types of lived alongside each other. And that accounts for the genetics of her three sons, because one came from an egg derived from the twin who cells dominate Jane's blood, while the two brother the other two brothers came from eggs derived from the other twin cells. Wow. So it's so even though one of the twins ended up being dominant in the individual, the other twin managed to have children. Like that's just like almost almost like a ghostly sense,

almost like from beyond the grave. Well, that's what's so amazing about this, this idea that you could carry with you someone else's cells and that Yeah, there's just this ghostly like sort of association that that would be informing also your children, your children's genetics. Uh so that that is an extreme case of this. Imagine your your siblings and you both have the same mother, but you have two different biological mothers, but those two biological mothers are

the same mother. It. Wow, it's really confusing. It's a bit of a head trip. But now um ivf in vitro fertilization increases the odds of having for tunnel twins about thirtyfold and is also associated with an increased risk of chimera. So it may not be I mean, they don't have a ton of research on on this so far, but it may not just be so crazy going forward, since IVF has been a pretty good option out there for a couple of decades. Now. Yeah, but this is

an extreme example of cells dominating your body. But it turns out that all of us have cells from someone else hanging out, which seems like an incredible statement, but it is true. And in this we're getting into the realm of microchimerism. Yeah. So this is when you possess a small number of cells in your body that are

not genetically your own. And this was first noticed in nine when a researcher at Stanford University found a few cells with Y sex chromosomes and a pregnant woman's blood and those cells had to have come from her son since women have only X chromosomes. She had male chromosomes in her body even though she's a pregnant female, right, So that that was the first inkling that something was going on. Um, so it turns out that all pregnant women carry some these are called fetals els by the way,

and DNA. Up to six percent of the free floating DNA in the mother's blood plasma comes from the fetus, and after the baby is born, those numbers plummet, but some cells remain and they actually just don't hang out there. They they do things in the body. And we'll talk a little bit more about that. Yeah, there's a wonderful quote in this New Scientists article by Nancy Shoot Beyond Birth,

and it goes as follows. She says, mother and child are engaged in a silent chemical conversation throughout pregnancy, with bits of genetic material and cells passing not only from mother to child, but also from child to mother. That's right in that two way street is the pacenta, right um. The pacenta is an organ it's built of cells from both the mother and the fetus, and it serves just as a reminder for everybody as a conduit for the

exchange of nutrients, gases, and waste. And so it's porous, and so you do have the cells um from from mother and child passing between each other. That's one of the ways that you can pass cells to each other, kind of a cellular backwash. I like that. Yeah, so you're backwash. After cells crossover, some get rounded up and killed by the new host immune system, but some of them take root in the body. They burrow into the heart, liver, kidneys,

spleen skin, pancreas, gall bladdering testines, among other places. They're kind of like squatters, really like they are clearly and not supposed to be there. Police round up the ones they can, but communities begin to take root in certain you know, abandoned buildings and back alleys. Yeah, and some of them become really productive members of body society. And this will discuss somebody not um Now. The fetal cells can also be passed through mother to infant, through nursing,

and also through transfusions and transplants. We're talking about bone marrow transplants and organ transplants, and that sort of brings up into question, you know, well, how do these cells figure into someone who's not even related to the person who you know, the organ was transplanted in. And we cannot answer these questions right now. In fact, this discovery of microchimerism actually brings up a lot more questions than answers.

But it's pretty fascinating stuff. Let's take a quick break and when we get back, we're going to talk about how those fetal cells hang out in your body and what they do. All right, we're back. Microchimerism. It's pretty nutty, it yeah. In fact, last year it was found that male DNA was discovered in the female brain, and this led everybody to understand that fetal cells are able to

cross the blood brain barrier. Now, this is that that sort of membrane that keeps out sort of the bad things that make sure that you don't get toxic chemicals that are traveling to your brain and and messing up the works in there um. But this fetal cell being able to cross the blood brain barrier was found in Researchers at the Department Biochemistry at the University of Alberta examined brain autopsy specimens from fifty nine women. They had died between the ages of thirty two and a hundred

and one. Now, male microcomerism, as it's called in this case, was detected in sixty three percent of the subjects and was distributed in multiple brain regions and was potentially persistent throughout the human lifespans. Of the sixty percent of the subjects, the oldest female in whom male fetal DNA was detected

in the brain was ninety four years old. Now this is kind of a huge thing because they had known that had migrated to different parts of the body, but they did not know what it was doing in the brain and if it even acted on the brain, and

that is still a big question mark. But they have looked at Alzheimer's disease because they know that it's more common in women who have had multiple pregnancies, and they thought that they would find that the number of fetal sales would be a lot greater in women with Alzheimer's compared to those who had no evidence for any sort of neurological disorders or disease. But this is the weird thing that the opposite was true of what they thought

was going to happen. There were fewer fetal derived cells and women with Alzheimer's. So they're still trying to figure out what sort of connection that might have. And you know, long term, there might be some sort of information about how those how those cells act on the brain, and you know, you have to also consider that in animal studies that microchimerate cells were found in maternal brains where they became nerve cells, it became active members of that

brain society, suggesting that they might have a functionality integrated. Now, of course, in all this you have to avoid the temptation to fall into a magical understanding of what's happening. When when we were researching this, I kept finding people talking about some of these studies on message boards and getting a little sentimental and at times a little goofy

about what it meant. Uh. And certainly you see that even with with ideas of organ transplants and limb transplants and mean sort of the idea that you know, go back to the little horror movie with Michael Caine. You get a hand transplanted onto your body and it's the hand of a criminal, and suddenly you're gonna do criminal things because it's the criminal's body part, that's the criminals hand, and now it's part of you. So you have to again,

you have to put that out of your head. Um. And there's plenty of weird, almost magical seeming stuff that's going on anyway, without bringing all of that nonsense and the equation. It's true, and you know, at some level though, it is symbolic and it's kind of nice to think that, you know, your mom is always carrying a bit of you around, and you're always carrying around some of your mom. But then but but again, it's just it's selves, it's

not it sells. But here's this just a complicated Like there's a little her in your flesh pocket on your side, and she's looking up at you like telling you to eat your piece. Totally is right now my flesh pocket. Thanks, Yeah, hey mom um. So here's here's something to complicated. There's a possibility that sells from an older sibling residing in the mother may find their way back across the placenta to a younger sibling. Now that's where it just gets

kind of gross. Like, here's the weird thing, Like, it's very possible that that I have not only my mom cells floating around, but my brothers and my daughters. Which is fine, I mean, obviously it's all working out. But with your daughter, I mean obviously there's a stronger connective. But you're you've discussed before how you and your brother are kind of different organisms, right, I mean you're rather different. Well, yeah,

of course we're different in many ways. But it is kind of interesting to me as at the second born. It's always like, man, seriously, you always get like, you know, second banana hand me down cells, right, thanks a lot. Uh No, twins, of course, identical twins can also exchange micro comeric cells through the sheriff of sentence, so us I don't think anything that's shocking, especially since we've already stablished they can merge together into one organism. Yeah, you know,

I don't put anything past them, exactly. You gotta watch out for the twins. They'll do it before you're born. If there are any twins out there listening, don't do it later. So much hard to absorb each other or across cells. Absorb each other or across cells. I mean, both are a little more difficult and a little more problematic if you do it as adults. It's true outside the womb, that is, there's a menial logistics there. Um. So here's some also interesting thing. There's evidence for competition

between cells from from grandmother in infant within the mother. Yeah. So that's where it gets a little dicey, and that's when we start to talk about autoimmune issues. Yeah, because we have. One of the problems with the autoimmune situation is that there's the theory is that you have essentially alien cells in the body. In the immune system detects alien cells, they're going to fight against them in the same way that they would have destroyed a number of

them immediately following the birth of the child. So you get that, you know, the problem of an autoimmune defense network attacking the body itself and all the complications that arise from that. Yeah, I mean because some autommune diseases, which current women three times more than in men, are thought to be associated with this problem, right, this sort of they're not assimilating, right, um, the Civil War in the Yeah, they're trying to figure out like why are

you here? Should you be here? Um? And that's when you see sort of things like multiple multiple sclorious as being exacerbated by this issue of fetal cells. Now, the good news is that, um, these fetal cells can kind of act like stem cells depending on where they are, Uh, they can actually help to repair damage tissue. And they're essentially a transplant of younger, healthier cells in depleted organs, So they might help protect against certain types of cancer.

So women with breast cancer, for instance, they generally have lower levels of microclimerrism than women who don't develop disease, and the suggests a possible role for fetal cells and helping to detect and destroy tumors because if you think about it, uh, those microclimeric cells from a pregnancy, they're recognized by the mom's immune system is belonging to the mother since they're genetically half identical to the mother, so

they get a pass. So they're they're sort of foreign to the immune system, but you know, because of the father's contribution. But they also this is the idea, they may prime the immune system to be alert for cells that are similar to the self but with genetic differences. So the idea is that having the presence of microchlimeric cells and the body could kind of ferret out cancer

cells and then stem the growth of any tumors. Sort of like, hey, we're on the alert for you, but we're also and you're fine, you get a pass, but these other guys they're not passing the test. So sometimes hand me down. That stuff is really good stuff. That's

the thing. Sometimes you can really make something out of it. Yeah, I mean, it's really cool and Nancy shoot, you had mentioned before in her Beyond Birth article says that fetal cells also appeared to migrate to injury sites and have been found in patients with thyroid and liver damage where they had morphed into organ cells. Wow, so like you can, Yeah, you can, on a very soular level, you can get into this idea that my daughter is healing me, my

my my son is healing my body well. And it's interesting that you say that because there was one account I can't remember which article, but one of them had said that there was someone who was going through cancer treatments and they kept that in mind. My son is helping to heal me through this. His cells are combating the cancer cells. And yes, there's a bit of magical

thinking to that, but it's sort of lovely. Yeah, just don't let it fill into like full on cannibalism, because I'd be like, I'm feeling at they're on a little thick here. But I bet if I ate the kid's arm,

then I maybe get a replenishment. It won't work. Messy defects. Okay. Yeah, Um, so of course we have to to start thinking about this in a future sense and One of the ways that researchers and scientists are is to actually look at dogs, because it turns out microchimerism is present in some dogs, and now makes setting the condition a lot easier because you're talking about lifespans ten to twenty years as opposed

to seventy eighty years. So they begin to kind of look at what that might mean, um, to have these cells acting like stem cells, or even acting against the museum, acting against museums, acting about against the immune system, and then how does this affect the world of human cloning. Well, it's not as straightforward as we thought, right, yeah, because

it's it's one thing. Because again, we we have this this notion that we get in our heads that that I am this one product and if you distole me down on these cells, on this DNA, on this person, and then if we can just recreate that data, then we can recreate, at least in a bodily sense, we can recreate ourselves. But now you're having to take into account.

I mean, we've discussed, um, you know, all the microbes that live inside us, and now we have to take into account different cellular communities from other individuals that make up who we are, how do you replicate that in a awning scenario? Right, and not to mention the microbiota that exists within everyone that is also again influencing how we moved through the world and what sort of diseases we may or may not get. Also have the genetics, right, Yeah, Well,

it's like with with cloning. It's um it reminds me of the movie The Boys from Brazil based on the book, where you had a plot to clone Hitler and it's the plot really has a has some fun with the idea of well, you would have to not only have a genetic duplicate, you would have to then recreate all the circumstances that made that person who they were. And uh in the film sort of operates on the idea that, well, the genetic side is simple to genetic side is just

pretty straightforward. But it's that conditioning that's where the problem lies. But we're saying more and more that the genetic side of things, the cellular side of things is almost equally complicated if you were actually trying to replicate an individual. Right, So this idea that we're just unique and we're just sort of preset with this program at birth, it's following away away, because now we all realize that we really truly are chimeras. Yeah, an innocence kind of ephemeral, I mean,

rather ephemeral. Yeah, all right, I just checked my pocket of flesh and mom says it's time to wrap it up. Okay, all right, well, uh well pocket of flesh mom, or we will call it an episode then. But we'd love to hear from all of you guys and gals out there. What do you think about this information? Um? How does it make you think about your relationships with with your parents, with your children, with strangers, you know, sibling, your sibling,

you know? How does it make you feel that your older, younger brother maybe a part of who you are on a solar level? Does that creep you out? Or does it give you hope? I don't know? And then how do you and then you know, to what extent do you draw thin magical interpretations of this into your indual world? Few we'd love to hear from you. You You can find us in all the normal places Stuff to blow your mind dot com. That's the mothership, that's where we put

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