Hidden Guests: Migrating Cells and How the New Science of Microchimerism Is Redefining Human Identity
By (Author) Lise Barneoud
Translated by Bronwyn Haslam
Afterword by J. Lee Nelson
Foreword by Olivia Campbell
Greystone Books,Canada
Greystone Books,Canada
11th February 2026
Canada
General
Non Fiction
Popular philosophy
Philosophy of science
Cellular biology (cytology)
Human biology
Hardback
200
Width 139mm, Height 215mm
What if some of your cells were not your own
A captivating and thought-provoking introduction to the fascinating scientific phenomenon of microchimerism.
In the astonishing process of human development, we grow from a single cell into an entire being, all of our cells derived from that first fertilized egg and containing a unique genetic code. Or so we thought. The recent scientific discovery of microchimerism disproves that widely believed notation, showing us that maybe not all of our cells are our own...
In Hidden Guests, science journalist Lise Barneoud explains microchimerism: the presence of genetically distinct cells that originated in another person. Scientists once believed these "hidden guests" to be both rare and harmful, but now know that we are all microchimeric, and that microchimeric cells help regenerate damaged tissues, prevent and treat diseases, and improve the odds of successful transplants and healthy pregnancies.
Weaving fascinating true stories and interviews with experts at the forefront of the research, Hidden Guests traces the history of this still emerging science while asking philosophical and probing questions about the implications of microchimerism to our understanding of immunity, biology, evolution, parental testing, criminal forensics, and the concept of individual identity. Barneoud makes the case for expanding our notions of both self and immunity: as ever-changing collectives of cells in relation, we are not unlike ecosystems. And like ecosystems, perhaps, the greater our diversity, the greater our resilience.
Barneoud also recounts the surprising and strange cases explained by microchimerism, such as:
With expert knowledge, Barneoud reveals all that is known about this science-in-the-making, which offers fertile ground for interpretation and imagination. Hidden Guests is a lively, thought-provoking, and essential introduction to this emerging scientific phenomenon.
Lise Barneoud is a freelance science journalist who regularly contributes to Le Monde and Mediapart. In addition to Hidden Guests, she is the author of two books about vaccines, Immunises and Vaccins. She won the 2008 Fondation Varenne award for science journalism in a national daily newspaper and the Trophees Signatures Sante's 2016 Grand Prix.