Scientists report first live birth of ‘chimeric’ monkey
The baby was born with ‘a high proportion’ of donor cells but survived only for 10 days, the researchers said.
Scientists have reported the first live birth of a “chimeric” monkey with stem cells taken from two embryos.
The embryos come from the same species of monkey – a crab-eating macaque – but are genetically distinct, the researchers said.
Chimeras are animals which contain groups of cells from two or more organisms with distinct types of DNA.
The baby monkey was born with “a high proportion” of donor cells – an average of 67% across the 26 different types of tissue, the scientists said.
Senior author Zhen Liu, of the Chinese Academy of Sciences, said: “This is a long-sought goal in the field.”
He added: “This work could help us to generate more precise monkey models for studying neurological diseases as well as for other biomedicine studies.”
Chimeras are important for studying embryonic development, but research has largely been restricted to mice.
While monkeys have previously been created in the lab using donor cells, the researchers said these creatures had a much lower contribution of cells from embryos “so you cannot really call them chimeric animals”.
Professor Mu-Ming Poo, scientific director of the Institute of Neuroscience at the Chinese Academy of Sciences, said: “Just having several cells (that) are partially distributed all over the monkey body with no real formation or clear structures – you cannot really say that is chimera, strictly speaking.
“So the difference here is that now we have a very high level of contribution, with the donor cells forming a big part of the tissues (and) complex structures all over the monkey body.”
Stem cells are the body’s raw materials from which all other cells with specialised functions are generated.
These cells were then injected into embryos that were four to five days old.
The embryos were implanted into female macaques, resulting in 12 pregnancies and six live births.
Of the six, one baby monkey was born alive and managed to survive for 10 days.
Analysis showed this male newborn had donor stem cells in 26 different types of tissue, ranging from 21% to up to 92%.
Meanwhile, a foetus that was miscarried was also “substantially chimeric”, the researchers said, with stem cell-derived cells observed in the brain, heart, kidney, liver, and parts of the digestive system.
The researchers said that their work complied with the national ethical regulations in China.
Prof Poo said: “The health of the monkey is still a problem.
“If we want to produce a monkey model, we have to have a better chimera that can live longer.”
