Chinese team grows humanised kidneys in pigs for first time, raising transplant hopes – and ethical concerns

Researchers at the Chinese Academy of Sciences Guangzhou Institutes of Biomedicine and Health published their findings in the journal Cell Stem Cell on Thursday, showing the potential to grow organs for transplant and research in pigs.

According to China Science Net, it is the first time a solid human organ has been grown inside another species.

Chinese scientists say ‘Midas’ touch helps to fine-tune CRISPR gene editing

Kidneys are one of the most commonly transplanted organs. However, donor kidney shortages make it difficult to provide healthy organs to recipients who need them.

Growing human organs in large mammal embryos “would be a groundbreaking solution” to this problem, according to the paper.

Out of more than 1,800 embryos involved in the study, five embryos succeeded in growing without degenerating, and these embryos grew kidneys containing 50 to 60 per cent human cells. Due to ethical considerations and the risk of embryonic degradation, gestation was stopped at 28 days, according to the paper.

02:26

Pig hearts successfully transplanted in brain-dead patients

Pig hearts successfully transplanted in brain-dead patients

A major concern in the creation of these interspecies chimeric embryos – embryos that contain cells of both human and pig origin – is the possibility of human cells contributing to the pig cell lineage, according to the paper.

Human cells were found in the brain and spinal cord of the embryos, but none were found around the genital ridge, suggesting the human cells did not differentiate into reproductive cells, Dai said.

According to the study, this could be overcome by eliminating genes responsible for the development of certain cell lineages, but this could also affect the growth of the kidneys.

The paper identified other challenges, such as the large number of embryos that degenerated during the experiments, the potential for organ rejection because of differing cell types and possible issues that could arise if the embryos had a longer gestation time.

Pig kidney works in brain-dead man’s body for over a month

There have been other attempts to fix the organ shortage problem, such as xenotransplantation, or transplanting an organ from one species to another. Genetic modification can be done to stop the expression of genes that cause rejection in xenotransplantation, according to New York University Langone Health.

The Chinese team’s study said xenotransplantation had “remarkable short-term success”, but genetic modifications had still not removed the potential for immune rejection.