Life is Emerging: Review of Siddhartha Mukherjee’s Song of the Cell
The DNA double helix is often the image spiraling at the center of 21st century advances in biomedicine and the growing bioeconomy. And yet, DNA is molecularly inert. DNA, the code for genes, is not alive and is not strictly necessary for life. Ought life be at the center of our communication of living systems? Is not the Cell a superior symbol of life and our manipulation of living systems?
A code for life isn’t a code without the life that instantiates it. A code for life must be translated. The cell is the basic unit of that translation. The cell is the minimal viable package of life as we know it. Therefore, cell biology is at the center of biomedicine’s greatest transformations, suggests Pulitzer-winning physician-scientist Siddhartha Mukherjee in his latest book, The Song of the Cell: The Exploration of Medicine and the New Human.
The Song of the Cell begins with the discovery of cells and of germ theory, featuring characters such as Louis Pasteur and Robert Koch, who brought the cell “into intimate contact with pathology and medicine.” This intercourse would transform biomedicine, leading to the insight that we can treat disease by thinking at the cellular level. The slightest rearrangement of sick cells might be the path toward alleviating suffering for the organism: eroding the cell walls of a bacterium while sparing our human cells; inventing a medium that coaxes sperm and egg to dance into cellular union for in vitro fertilization (IVF); designing molecular missiles that home to the receptors decorating the exterior of cancer cells; teaching adult skin cells to remember their embryonic state for regenerative medicines.
Mukherjee uses the bulk of the book to elucidate key cell types in the human body, along with their “connective relationships” that enable key organs and organ systems to function. This includes the immune system, the heart, the brain, and so on. Mukherjee’s distinctive style features compelling anecdotes and human stories that animate the scientific (and unscientific) processes that have led to our current state of understanding. In his chapter on neurons and the brain, for example, he integrates Santiago Ramon y Cajal’s meticulous black ink sketches of neurons into Mukherjee’s own personal encounter with clinical depression. In one lucid section, he interviews Dr. Helen Mayberg, a pioneering neurologist who takes seriously the descriptive power of her patients’ metaphors, as they suffer from “caves,” “holes,” “voids,” and “force fields” that render their lives gray. Dr. Mayberg aims to stimulate patients’ neuronal cells in a manner that brings back the color.
Beyond exposing the insight and inventiveness that has arisen out of cell-based thinking, it seems that Mukherjee’s bigger project is an epistemological one. The early chapters of The Song of the Cell continually hint at the potential for redefining the basic unit of biology as the cell rather than the gene. The choice to center biomedicine around cells is, above all, a conspicuous choice not to center it around genes (the subject of Mukherjee’s previous book, The Gene), because genes dominate popular science communication.
This choice of cells over genes is most welcome. Cells are alive. Genes are not. Letters—such as the As, Cs, Gs, and Ts that represent the nucleotides of DNA, which make up our genes—must be synthesized into a word or poem or song that offers a glimpse into deeper truths. A key idea embedded in this thinking is that of emergence. Whether in ancient myth or modern art, creation tends to be an emergent process, not a linearly coded script. The cell is our current best guess for the basic unit of life’s emergence, turning a finite set of chemical building blocks—nucleic acids, proteins, sugars, fats—into a replicative, evolving system for fighting stasis and entropy. The cell’s song is one for our times, for it is the song of biology’s emergence out of chemistry and physics, into the “frenetically active process” of homeostasis.
Re-centering our view of biology has practical consequences, too, for how we think about diagnosing and treating disease, and for inventing new medicines. Centering cells presents a challenge: which type of cell to place at the center? Rather than default to the apparent simplicity of DNA as a symbol because it represents the one master code for life, the tension in defining the diversity of cells—a mapping process still far from complete in cutting-edge biology laboratories—can help to create a more thoughtful library of cellular metaphors to shape both the practice and communication of biology.
Further, effective problem solving is often about operating at the right level, or the right scale. The cell feels like appropriate level at which to interrogate many of the diseases that ail us, because the senses that guide our own perceptions of sickness and health—the smoldering pain of inflammation, the tunnel vision of a migraine, the dizziness of a fluttering heart—are emergent.
This, unfortunately, is sort of where Mukherjee leaves the reader, under-exploring the consequences of a biology of emergence. Many practical and profound questions have to do with the ways that each scale of life feeds back on the others. In a tome on Cells and “the future human” I wished that Mukherjee had created more space for seeking the ways that cells will shape and be shaped by the future, of humanity and otherwise.
We are entering a phase of real-world bioengineering that features the modularization of cellular parts within cells, of cells within organs, of organs within bodies, and of bodies within ecosystems. In this reality, we would be unwise to assume that any whole is the mere sum of its parts.
For example, when discussing the regenerative power of pluripotent stem cells, Mukherjee raises the philosophical thought experiment of the Delphic boat, also known as the Ship of Theseus. The boat is made of many pieces of wood, each of which is replaced for repairs over the years, with the boat’s structure unchanged. Eventually none of the boat’s original wood remains: Is it the same boat?
Mukherjee raises the Delphic boat in one paragraph at the end of the chapter on stem cells, as a metaphor related to the possibility of stem cell-enabled regeneration in perpetuity. He does not follow any of the threads of potential answers. Given the current state of cellular engineering, about which Mukherjee is a world expert from his work as a physician-scientist, this book could have used an entire section dedicated to probing this question and, importantly, the ways this thought experiment falls apart.
We are entering a phase of real-world bioengineering that features the modularization of cellular parts within cells, of cells within organs, of organs within bodies, and of bodies within ecosystems. In this reality, we would be unwise to assume that any whole is the mere sum of its parts. Wholeness at any one of these scales of life—organelle, cell, organ, body, ecosystem—is what is at stake if we allow biological reductionism to assume away the relation between those scales.
In other words, Mukherjee succeeds in providing a masterful and compelling narrative of the lives of many of the cells that emerge to enliven us. Like his previous books, it is a worthwhile read for anyone curious about the role of cells in disease and in health. And yet, he fails to offer the broader context of The Song of the Cell.
As leading agronomist and essayist Wes Jackson has written, “The sequence of amino acids that is at home in the human cell, when produced inside the bacterial cell, does not fold quite right. Something about the E. coli internal environment affects the tertiary structure of the protein and makes it inactive. The whole in this case, the E. coli cell, affects the part—the newly made protein. Where is the priority of part now?” [1]
Beyond the ways that different kingdoms of life translate the same genetic code, the practical situation for humanity today relates to the ways that the different disciplines of modern life use values and culture to influence our genes, cells, bodies, and environment. It may be that humans will soon become a bit like the Delphic boat, infused with the buzz of fresh cells to repopulate different niches within our bodies, for healthier, longer lives. But in biology, as in writing, a mixed metaphor can cause something of a cacophony. For we are not boats with parts to be replaced piecemeal. And nor are whales, nor alpine forests, nor topsoil. Life isn’t a sum of parts, and neither is a song that rings true.
[1] Wes Jackson, "Visions and Assumptions," in Nature as Measure (p. 52-53).
No, the New COVID Vaccine Is Not "Morally Compromised"
The approval of the Johnson & Johnson COVID-19 vaccine has been heralded as a major advance. A single-dose vaccine that is highly efficacious at removing the ability of the virus to cause severe disease, hospitalization, and death (even in the face of variants) is nothing less than pathbreaking. Anyone who is offered this vaccine should take it. However, one group advises its adherents to preferentially request the Moderna or Pfizer vaccines instead in the quest for morally "irreproachable" vaccines.
Is this group concerned about lower numerical efficacy in clinical trials? No, it seems that they have deemed the J&J vaccine "morally compromised". The group is the U.S. Conference of Catholic Bishops and if something is "morally compromised" it is surely not the vaccine. (Notably Pope Francis has not taken such a stance).
At issue is a cell line used to manufacture the vaccine. Specifically, a cell line used to grow the adenovirus vector used in the vaccine. The purpose of the vector is to carry a genetic snippet of the coronavirus spike protein into the body, like a Trojan Horse ferrying in an enemy combatant, in order to safely trigger an immune response without any chance of causing COVID-19 itself.
It is my hope that the country's 50 million Catholics do not heed the U.S. Conference of Bishops' potentially deadly advice and instead obtain whichever vaccine is available to them as soon as possible.
The cell line of the vector, known as PER.C6, was derived from a fetus that was aborted in 1985. This cell line is prolific in biotechnology, as are other fetal-derived cell lines such as HEK-293 (human embryonic kidney), used in the manufacture of the Astra Zeneca COVID-19 vaccine. Indeed, fetal cell lines are used in the manufacture of critical vaccines directed against pathogens such as hepatitis A, rubella, rabies, chickenpox, and shingles and were used to test the Moderna and Pfizer COVID-19 vaccines (which, accordingly, the U.S. Conference of Bishops deem to only raise moral "concerns").
As such, fetal cell lines from abortions are a common and critical component of biotechnology that we all rely on to improve our health. Such cell lines have been used to help find treatments for cancer, Ebola, and many other diseases.
Dr. Andrea Gambotto, a vaccine scientist at the University of Pittsburgh School of Medicine, explained to Science magazine last year why fetal cells are so important to vaccine development: "Cultured [nonhuman] animal cells can produce the same proteins, but they would be decorated with different sugar molecules, which—in the case of vaccines—runs the risk of failing to evoke a robust and specific immune response." Thus, the fetal cells' human origins are key to their effectiveness.
So why the opposition to this life-saving technology, especially in the midst of the deadliest pandemic in over a century? How could such a technology be "morally compromised" when morality, as I understand it, is a code of values to guide human life on Earth with the purpose of enhancing well-being?
By any measure, the J&J vaccine accomplishes that, since human life, not embryonic or fetal life, is the standard of value. An embryo or fetus in the earlier stages of development, while harboring the potential to grow into a human being, is not the moral equivalent of a person. Thus, creating life-saving medical technology using cells that would have otherwise been destroyed is not in conflict with a proper moral code. To me, it is nihilistic to oppose these vaccines on the grounds cited by the U.S. Conference of Bishops.
Reason, the rational faculty, is the human means of knowledge. It is what one should wield when approaching a scientific or health issue. Appeals from clerics, devoid of any need to tether their principles to this world, should not have any bearing on one's medical decision-making.
In the Dark Ages, the Catholic Church opposed all forms of scientific inquiry, even castigating science and curiosity as the "lust of the eyes": One early Middle Ages church father reveled in his rejection of reality and evidence, proudly declaring, "I believe because it is absurd." This organization, which tyrannized scientists such as Galileo and murdered the Italian cosmologist Bruno, today has shown itself to still harbor anti-science sentiments in its ranks.
It is my hope that the country's 50 million Catholics do not heed the U.S. Conference of Bishops' potentially deadly advice and instead obtain whichever vaccine is available to them as soon as possible. When judged using the correct standard of value, vaccines using fetal cell lines in their development are an unequivocal good -- while those who attempt to undermine them deserve a different category altogether.
Dr. Adalja is focused on emerging infectious disease, pandemic preparedness, and biosecurity. He has served on US government panels tasked with developing guidelines for the treatment of plague, botulism, and anthrax in mass casualty settings and the system of care for infectious disease emergencies, and as an external advisor to the New York City Health and Hospital Emergency Management Highly Infectious Disease training program, as well as on a FEMA working group on nuclear disaster recovery. Dr. Adalja is an Associate Editor of the journal Health Security. He was a coeditor of the volume Global Catastrophic Biological Risks, a contributing author for the Handbook of Bioterrorism and Disaster Medicine, the Emergency Medicine CorePendium, Clinical Microbiology Made Ridiculously Simple, UpToDate's section on biological terrorism, and a NATO volume on bioterrorism. He has also published in such journals as the New England Journal of Medicine, the Journal of Infectious Diseases, Clinical Infectious Diseases, Emerging Infectious Diseases, and the Annals of Emergency Medicine. He is a board-certified physician in internal medicine, emergency medicine, infectious diseases, and critical care medicine. Follow him on Twitter: @AmeshAA
When NASA's Perseverance rover landed successfully on Mars on February 18, 2021, calling it "one giant leap for mankind" – as Neil Armstrong said when he set foot on the moon in 1969 – would have been inaccurate. This year actually marked the fifth time the U.S. space agency has put a remote-controlled robotic exploration vehicle on the Red Planet. And it was a female engineer named Donna Shirley who broke new ground for women in science as the manager of both the Mars Exploration Program and the 30-person team that built Sojourner, the first rover to land on Mars on July 4, 1997.
For Shirley, the Mars Pathfinder mission was the climax of her 32-year career at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California. The Oklahoma-born scientist, who earned her Master's degree in aerospace engineering from the University of Southern California, saw her profile skyrocket with media appearances from CNN to the New York Times, and her autobiography Managing Martians came out in 1998. Now 79 and living in a Tulsa retirement community, she still embraces her status as a female pioneer.
"Periodically, I'll hear somebody say they got into the space program because of me, and that makes me feel really good," Shirley told Leaps.org. "I look at the mission control area, and there are a lot of women in there. I'm quite pleased I was able to break the glass ceiling."
Her $25-million, 25-pound microrover – powered by solar energy and designed to get rock samples and test soil chemistry for evidence of life – was named after Sojourner Truth, a 19th-century Black abolitionist and women's rights activist. Unlike Mars Pathfinder, Shirley didn't have to travel more than 131 million miles to reach her goal, but her path to scientific fame as a woman sometimes resembled an asteroid field.
As a high-IQ tomboy growing up in Wynnewood, Oklahoma (pop. 2,300), Shirley yearned to escape. She decided to become an engineer at age 10 and took flying lessons at 15. Her extraterrestrial aspirations were fueled by Ray Bradbury's The Martian Chronicles and Arthur C. Clarke's The Sands of Mars. Yet when she entered the University of Oklahoma (OU) in 1958, her freshman academic advisor initially told her: "Girls can't be engineers." She ignored him.
Years later, Shirley would combat such archaic thinking, succeeding at JPL with her creative, collaborative management style. "If you look at the literature, you'll find that teams that are either led by or heavily involved with women do better than strictly male teams," she noted.
However, her career trajectory stalled at OU. Burned out by her course load and distracted by a broken engagement to marry a fellow student, she switched her major to professional writing. After graduation, she applied her aeronautical background as a McDonnell Aircraft technical writer, but her boss, she says, harassed her and she faced gender-based hostility from male co-workers.
Returning to OU, Shirley finished off her engineering degree and became a JPL aerodynamist in 1966 after answering an ad in the St. Louis Post-Dispatch. At first, she was the only female engineer among the research center's 2,000-odd engineers. She wore many hats, from designing planetary atmospheric entry vehicles to picking the launch date of November 4, 1973 for Mariner 10's mission to Venus and Mercury.
By the mid-1980's, she was managing teams that focused on robotics and Mars, delivering creative solutions when NASA budget cuts loomed. In 1989, the same year the Sojourner microrover concept was born, President George H.W. Bush announced his Space Exploration Initiative, including plans for a human mission to Mars by 2019.
That target, of course, wasn't attained, despite huge advances in technology and our understanding of the Martian environment. Today, Shirley believes humans could land on Mars by 2030. She became the founding director of the Science Fiction Museum and Hall of Fame in Seattle in 2004 after leaving NASA, and to this day, she enjoys checking out pop culture portrayals of Mars landings – even if they're not always accurate.
After the novel The Martian was published in 2011, which later was adapted into the hit film starring Matt Damon, Shirley phoned author Andy Weir: "You've got a major mistake in here. It says there's a storm that tries to blow the rocket over. But actually, the Mars atmosphere is so thin, it would never blow a rocket over!"
Fearlessly speaking her mind and seeking the stars helped Donna Shirley make history. However, a 2019 Washington Post story noted: "Women make up only about a third of NASA's workforce. They comprise just 28 percent of senior executive leadership positions and are only 16 percent of senior scientific employees." Whether it's traveling to Mars or trending toward gender equality, we've still got a long way to go.