“Hidden Guests illustrates Barnéoud’s amazing talent for weaving complicated and seemingly isolated scientific observations into a captivating narrative that makes microchimeric cells come to life. This inspiring tapestry of scientific adventures is a must-read for anyone curious about science and self-identity – and willing to let their imaginations run wild.” — Sing Sing Way, Nature

“A fascinating book. Hidden Guests is more lyrical than narrative. Ms. Barnéoud ruminates on how microchimerism might change our understanding of ourselves.” – Sam Kean, Wall Street Journal

” Told in beautiful, sometimes bordering on poetic, language with occasional snark and humor thrown in, the book upends some of the very foundations of medicine, immunology, and genetics. And, having been rooted in cutting-edge research, it rocks our philosophical concept of self.”— Lina Zeldovich, Undark

“This book is a great insight into the new science of microchimerism. It shows how this fascinating new field brings with it profound implications for medicine, and even what it means to be human, finds” — Helen Thomson, New Scientist

“Much of our biological and cultural identity stems from the idea that our bodies (and lives) stem from just one fertilised egg and a mix of our parents’ DNA. The remarkable Hidden Guests, by science journalist Lise Barnéoud, throws a grenade into this idea” — Tom Ireland, The Biologist

Some books change your view of the world.  — Libération

We can never say enough about the beauty of “gaps” in the history of science. Of these moments when the incongruous invites itself to the table of certainties, where measuring instruments make the reigning theories lie. (…) In Les Cellules buissonnières, the fascinating essay by Lise Barnéoud, researchers recount their encounter with a hitherto “unthinkable” reality.  — Télérama

In Les Cellules buissonnières, journalist Lise Barnéoud tells how microchimerism shakes up the limits of the individual.  — Le Monde

A fascinating book. — France Culture

A captivating read! — La Recherche

An incredible journey inside our body, discovering cellular populations whose existence challenges the limits of our being. — Le Point

Unbelievable and astonishing. — RFI

A rich investigation, in contact with the main global players in this unusual field of research. — Sciences et avenir

It’s a field of research that could change absolutely everything, and overturn our long-held certainties. — Ça m’intéresse

An excellent popular science book. — France Bleu Drôme Ardèche

Lise Barnéoud invites us to reinvest the scientific field with a form of dream and poetry, by imagining the immensity of what remains to be discovered. — Bookstore La Nuit des temps, Rennes

A revolution in progress, a dizzying test! — Bookstore Le Bonheur, Montrouge

How microchimerism disrupted science.

Microchimerism is not a word most people have heard, and few fully grasp the reality it describes, even as its discovery overturns our very concept of self.

We thought we knew that our cells are all made up of our DNA, this unique code that defines our identity. We are now discovering that this ‘I’ is deceiving; others’ cells are at work within our bodies.

The phenomenon starts in utero, with a complex choreography of cells. It involves not only the mother and fetus, but extends back generations, and includes siblings and vanishing twins – those embryos which were created at the same time that we were, but which disappeared so rapidly that no one noticed. During this unseen “dance”, other people’s cells become our own, the past creeps into the future and the future goes back in time.

About 20 years ago, the microbiome discovery taught us that we were half composed of microorganisms (viruses, bacteria, fungi, etc.) Today we realize that even our human cells don’t belong to us. This is a major upheaval, both to medical science and to the way we understand our identity. These foreign cells communicate with our cells, participate in the functioning of our organs, help repair damaged tissue, and can aid in fighting infections. Microchimerism is a new scientific frontier that ignites the imagination and is proving fertile ground for ideologues of all stripes, turning laboratories into political arenas.

Wandering Cells: Strangers Within Us presents a patient and pedagogical exploration of this fascinating phenomenon, which opens the door to a dizzying array of futures, the shapes of which are only beginning to resolve. Lise Barnéoud is pulling back the curtain on science in the making. She dedicated over a year to this worldwide investigation, side-by-side with the men and women who are shaping the future of science.