Pioneering Research: Growing Human Kidneys in Pigs

This is a revolutionary move towards addressing the dire demand for organ transplants worldwide.

In a significant breakthrough, researchers in China have grown early-stage human kidneys within pigs, marking a substantial stride towards potentially producing animal transplantable organs. This development comes at a crucial time when more than 100,000 people in the United States alone are on the national transplant waiting list, with an estimated 17 individuals dying each day due to the lack of donor organs. The demand for kidneys is exceptionally high, with almost 89,000 Americans requiring one as of September.

Chimeric Organisms: A Glimmer of Hope

The possibility of growing human organs inside pigs is a promising solution to the shortage of available organs for transplant patients. This process involves creating chimeric organisms comprising cells from different species. Although this concept is not new, previous studies have successfully grown humanized blood vessels and skeletal muscle in pigs. The latest breakthrough in developing kidneys within pigs marks a significant advancement in this field.

A Brief History of Animal Chimeras

The pursuit of creating animal chimeras in laboratories started several decades ago. The first reported success was in 1984 with the creation of goat-sheep illusions in Cambridge, England. More recently, in 2019, scientists made the first embryos that were part human and part monkey. Although these embryos were eventually destroyed, the experiment opened doors to more advanced research in this direction.

The Current Study

In the current study, researchers at Guangzhou Institutes of Biomedicine and Health in China injected over 1,800 pig embryos with human stem cells. These chimeric embryos were then transferred into the wombs of 13 female pigs. After 28 days, the pregnancies were halted, and the sources were extracted for examination. The researchers found that all five embryos had kidneys that were developing typically and contained up to 65 percent of human cells.

The Challenges and the Solutions

Despite these promising results, integrating cells from pigs and humans is challenging. One significant hurdle is that pig cells tend to outcompete human cells when transplanted into animal tissue, causing the human cells to die off quickly. To overcome this, the researchers used the gene-editing tool CRISPR to knock out two genes in the pig embryos responsible for kidney development. This modification halted the formation of pig kidneys and created a niche where the humanized kidneys could develop.

Another challenge is ensuring that the humanized organ has sufficient room to develop within the animal. In response, the researchers manipulated a batch of regular human cells into pluripotent stem cells that can transform into any cell type in the body. These stem cells were then injected into the pig embryos. Additionally, the researchers supplied the seeds with a unique cocktail of nutrients to help both the human and pig cells survive, given their different needs.

The Future of Organ Transplants

Although significant progress has been made, the development of entirely human organs inside pigs is still a long way off. There are concerns about the potential risks of cancer due to the overexpression of specific genes. Additionally, even if scientists succeed in growing humanized organs inside pigs, they may not be compatible with the human immune system. Therefore, extensive animal testing and further research are necessary to determine the feasibility of this approach for organ transplantation.

Despite these challenges, the potential benefits of this pioneering research are enormous. It can potentially revolutionize organ transplant procedures and save countless lives worldwide. With continued research and development, we may soon be able to meet the demand for organ transplants, ending the long and painful wait for thousands of patients worldwide.