Breasts (18 page)

He continued in his riveting, pretend-you’re-a-baby mode. Clearly he’s a man used to speaking to glassy-eyed undergraduates. “If you’re a preemie and you probably came out by C-section and you’re not breast-fed, you’re acquiring bacteria in your gut from the hospital that will reside there for the rest of your life.” He winces. “That’s not the way you want to do it. Normally, the mother hands down bacteria to her infant by means we still don’t fully understand. If there’s a successful transfer, it will be handed down mother-todaughter for generations. Now we think one C-section could break that chain.” He plunks down his coffee cup. “You’ve lost touch with your genetic ancestry.”

Could another way to break the microbial chain occur if the mother herself was not breast-fed? Are we now looking at a couple of generations of orphaned intestines, cut off from their full bacterial legacy? I asked German and he nodded. “Exactly.” He said he’d like to see every baby (who doesn’t receive breast milk) get a dose of
Bifidus infantis
at birth, like a vitamin K shot.

This bacterium is one of German’s favorites.
Bifidus infantis
has seven hundred genes, all of which evolved to live and thrive in a unique microbial environment: the infant gut. There,
B. infantis
eats the oligosaccharides that rain down in breast milk. The bacterium produces proteins that pull those special sugars inside it, where they get broken down and digested so that they are unavailable
for other (worse) bacteria. Furthermore, said German, “
Bifidus
can overwhelm bad bacteria. It recruits a whole schoolyard of supportive organisms.” As I’ve said, these human milk oligosaccharides are not found anywhere else in nature. “It’s clear that these bacteria co-evolved with our oligosaccharides,” continued German. “It’s our true symbion.”

It’s good to know all this, but it’s also another intense failing for modern mothers to feel guilty about. I couldn’t help but wonder if I’d somehow flubbed the important microbial hand-off to my children. Some of the blame I could cast to my mother, who might not have given me the adequate goods in just four weeks of nursing. But I get a pit in my stomach when I think of the repeated rounds of antibiotics I took for mastitis while nursing my son: cephalexin, amoxicillin, dicloxicillin. Was I killing off everything good in his gut as well as in mine?

The adult gut can recover from antibiotics within a few months because of mysterious reserves of bacteria in our bodies, our housemates, and to some extent, our food. But the infant, who is bacterially “naive” and building colonies for the first time, might not. These thoughts snowballed in my mind, because my son has had gastrointestinal trouble for most of his life. The poor guy is chronically constipated. One pediatric gastrointestinal specialist I took him to shrugged off a search for root causes, saying, “Well, some people just have slow motility, like a sloth.” That’s my son, the sloth.

I sought out David Newburg, a biologist from Boston who has been studying the connections between breast milk, intestinal microflora, and disease for over two decades. A tall, tanned man with a trim goatee, I often saw him enjoying the Peruvian pastry table, as did I.

“Can I ask you a personal question?”

Newburg raised his eyebrows. “In that case, I’m going to need two tea sandwiches,” he replied.

I told him the story of my mastitis and the antibiotics. Was my son’s problem my fault?

“It’s definitely possible,” he said, making me feel wretched. Good tests to diagnose the gut’s array of normal and abnormal microflora are still a few years out, he explained. Changing the microflora is even harder. Someday, though, these things will be a routine part of medical care. In the meantime, Newburg recommended Ben regularly take probiotics (such as the lactobacillus found in yogurt and supplements) as well as eat foods rich in prebiotics (the complex carbohydrates that beneficial bacteria need to thrive). Although breast milk is the world’s best source of prebiotics for humans, they can also be found in Jerusalem artichoke, Belgian endive, onions, asparagus, and some other plants not terribly alluring to a nine-year-old.

I told Newburg what Bode had said about it being so difficult and expensive to synthesize human-milk prebiotics.

“Hah!” said Newburg, baring a little professional rivalry. “We know how to do it. Come visit my lab. We’re up to our necks in shit.”

I know, most people would have declined this offer and fled. But by now I had fallen too far down the milky rabbit hole and was weirdly entranced by gut flora, that unexpected and invisible pillar of human health. I kept thinking of German’s image of us living at the behest of the microorganisms, not the other way around— “Who’s really cultivating whom?” he’d asked dramatically. The microflora outnumber us by a lot. There are ten times more microbacteria in our guts than there are cells in the human body. A song lyric kept playing in my head: Patty Griffin’s “You are not alone.”

And so, a few weeks later I was negotiating the steep, rainslicked steps outside of Higgins Hall on the Boston College campus.
I maneuvered past a rather severe statue of St. Ignatius and into the new and immaculate molecular sciences building, where Newburg commands a spacious realm on the fourth floor.

Wearing black jeans, a black golf shirt, and sandals, Newburg welcomed me into his lab. It looked like a cross between a kitchen and a Kinko’s. The boxy, beige machines are actually mass spectrometer contraptions, such as the snazzy new “triple quad.” It sounds like a Vail chairlift and looks like a photocopier, but it costs around half a million dollars and breaks down molecules into gradually smaller components. To distinguish and identify different molecules, these machines utilize color, molecular weight, or, my favorite, “time of flight.” This one sends molecules pinging down a zigzag chamber and then up a small cylinder the size of a stovepipe. No two longchain molecules make the lap (or, technically, have the same mass-to-charge ratio) in exactly the same way. Many of the substances Newburg is finding in human milk have never been seen before.

The lab is a bank for two main kinds of substances: human diseases and the breast milk that fights them. To obtain the diseasecausing organisms, Newburg collects infant feces. He and his colleagues isolate the pathogens (such as botulinum, campylobacter,
Vibrio cholerae,
and
Escherichia coli
) and grow them in an anaerobic chamber similar to our guts. He especially treasures a source in Mexico, a clinic that sends him samples rich in things like rotavirus. Otherwise, he finds them through local hospitals and lactatingmom networks. “Just to handle baby poop is an incredibly long and complex process,” he said, involving informed-consent paperwork and hospital review boards. Some of his fecal freezers are set to –80 degrees Celsius, the temperature of outer space. Other incubators mimic body temperature for growing human cells from the lining of intestines and lungs (breast milk is also ferociously adept at fighting
pneumonia). Leaving the tissue culture room, I saw a tube the size of a beer glass stuffed with what looks like raw steak. “That’s a liver,” said Newburg.

For him, analyzing baby shit is practical and urgent. Globally, 1.4 million children under five die each year from diarrheal illnesses. This makes sense if you consider that 20 percent of the world’s population doesn’t use any sort of toilet, and nearly half doesn’t have access to decent sanitation. Nearly a billion people don’t live near clean drinking water. At the same time, human milk is so effective at fighting infections that if all children were exclusively breast-fed the first six months of life, one in five childhood deaths could be prevented.

“Breast-fed poop doesn’t smell too obnoxious,” Newburg said. “It’s more like sour cheese or milk. Frankly, even as a guy, I got used to it.” Newburg led me to a normal-looking fridge to show off some of his precious collection, but he gasped when he saw the door was slightly ajar. A box of test tubes was wedged clumsily into the door. A small puddle had formed on the floor below it. “Oh no,” he said. A lab tech had accidently left the door open overnight. It occurred to me that the only thing worse than a freezer full of poop was a freezer full of thawing poop—especially for Newburg, who would have to deal with the scientific consequences. He lifted a test tube packed with brown goo and shook it. “I think this whole fridge is compromised,” he muttered.

After he washed his hands, we settled into his adjacent office for a chat. A poster-sized, soft-focus photograph of a blonde woman nursing a baby loomed above his desk (“My wife doesn’t like it,” he said of the image). Books such as
Phospholipids Handbook, Gray’s Anatomy,
and
Modern Nutrition in Health and Disease
packed the front wall. Like many men in this field, Newburg told me he didn’t start out intending to study lactation. His field was neuroscience. But
running a rat experiment three decades ago, he noticed his formulafed pups “never performed as well as the nursed ones. A normal person would have said, ‘fine,’ but not me. I took a sabbatical to study essential nutrients for brain development,” and the rest is history.

He became intrigued by the indigestible oligosaccharides, and soon he had established that they must function to fight pathogens in the infant gut. In the 1980s, his lab (then at Harvard) rather startlingly discovered that human milk inhibits the transmission of HIV, among other things. He didn’t know exactly how, and he still doesn’t, although he’s closer to knowing which oligosaccharide compound is responsible. “We do know that the transmission of HIV through milk is much less than through any other medium,” he said. He fully expects to identify the heroic sugar complex, then make it and offer it up as a therapy in the real world. “We’ll study it and we’ll find out,” he said. “It would be much more effective than a vaccine, I think.”

Already, Newburg’s company, Glycosyn (he cofounded it in 2002), is making a “2-linked fucosyloligosaccharide” known to help ward off norovirus,
E. coli,
cholera, and campylobacter. Because, as Bode pointed out, it’s too expensive to synthesize these molecules from scratch, Newburg has a different strategy. He’s teaching yeast to produce them for him by converting a natural product they make into a building block called fucose. He then takes that and links it to lactose “because that’s what mom does.” Some other companies in Europe are making oligosaccharides from plants or cow’s milk and putting them in infant food, but Newburg says it’s not the same.

Glycosyn will start testing its product in humans sometime in 2012 or 2013. Newburg told me the final product will probably resemble a sugar packet that can be mixed into food or formula. It will be ideal for babies on formula or babies and toddlers who are weaning, which can be a treacherous process in developing countries
with unsafe food and water. Newburg’s product will be like NutraSweet for the survival set, the mysterious stuff of breasts purified into a paper packet.

As someone who extols the benefits of breast milk but wants to improve formula, Newburg has garnered some criticism from both sides. If there’s one thing the lactivists hate, it’s better formula, because they think it can never really be good enough. “It’s frustrating to see moms who don’t breast-feed, but I understand why some don’t,” said Newburg. “I don’t think their children should be punished. My orientation is to the baby.”

LECHISTAS, PREPARE YOURSELVES: FORMULA WILL GET BETTER
and so will a bunch of other foods, supplements, therapies, and medications thanks to the unlocked secrets of milk. A quick survey of what other biotech companies are doing shows the range of benefits being urgently, greedily, attributed to human milk. It’s important to remember from chapter 2 that lactation likely evolved from the immune system; its primary function was not nutrition but protection. Most of the cells in milk are macrophages, which disable viruses, fungi, and bacteria. I already mentioned Prolacta Bioscience, which is concentrating and pasteurizing donated human milk—and then selling it—as an “immunonutrition” supplement for preemies weighing less than 2.5 pounds. In the Brave New World department, several companies are reengineering other animals to produce the unique ingredients of human milk, because it’s still easier and cheaper to raise a herd of transgenic goats than it is to beg or buy large quantities of milk from suburban mothers.

One of the most sought-after components of human milk is a glycoprotein called lactoferrin. Known to have keen anti-inflammation,
antioxidant, and anti-infective properties, it’s an iron-binding machine that outcompetes pathogens. Lactoferrin can also be found in tears and saliva and genital secretions, but in tiny percentages compared to milk. It’s possible to inject animal embryos with the human gene that makes it. Some companies are genetically altering cows, goats, and even rabbits, then isolating the human lactoferrin from the milk. One Japanese company has begun marketing capsules, which it calls “Lactoferrin Gold.” Three
liters
of modified cow’s milk are needed to make one capsule. I can see why they named it after a precious ore. To make lactoferrin, another company bred a whole herd of cows from one long-dead transgenic bull named Herman. But altered mold fungus can make it too. A biotech outfit with over a hundred lactoferrin patents intends to use the fungal product for fighting cancer and healing wounds.

According to one economic analysis, if lactoferrin were added to infant formula, it would create an extra $15 billion in value. If added to eye drops, oral hygiene, soaps, and shampoos, another $10 billion. Cancer drugs: $19 billion.

That’s just lactoferrin, but there is also active research on other components. Stem cells, for example, teem from human milk, particularly from the dense colostrum produced in the early days of nursing. Before the baby is five days old, she’ll receive five million stem cells from the mother. No one really knows why. Are they colonizing the baby in case she needs them? Are they just a by-product from the newly functional mammary gland? Then there’s a very cool protein called alpha-lactalbumin. In the acids of the infant stomach, the protein refolds itself and picks up a neighboring fatty acid, also from the milk, forming a new complex. The scientist who discovered it fifteen years ago, a Swede named Catharina Svanborg, dubbed it HAMLET, for
h
uman
a
lph
a
-
l
actalbumin
m
ade
le
thal to
t
umor cells.