New research has brought stem cell transplantation without immune suppression closer to reality.
Researchers at the University of Arizona Health Sciences say they are one step closer to understanding immunological rejection, a barrier to regenerative medicine, after genetically modifying pluripotent stem cells to evade immune recognition.
The findings offer a viable path forward for pluripotent stem cell-based therapies to restore tissues that are lost in diseases such as Type 1 diabetes or macular degeneration.
“There has been a lot of excitement for decades around the field of pluripotent stem cells and regenerative medicine,” said principal investigator Deepta Bhattacharya, a Professor in the UArizona College of Medicine – Tucson’s Department of Immunobiology. “What we have learned from the experiences of organ transplantation is that you have to have matched donors, but the person receiving the transplant often still requires lifelong immune suppression, and that means there is increased susceptibility to infections and cancer.”
To test their hypothesis, Bhattacharya and the research team used CRISPR-Cas9 technology to remove the genes they believed were involved in immune rejection.
The research team tested the modified stem cells by placing them into mice with normal, fully functioning immune systems. The results were promising – the genetically engineered pluripotent stem cells were integrated and persisted without being rejected.
“That has been the holy grail for a while. You might actually have a chance of being able to perform pluripotent stem cell-based transplants without immune suppressing the person who is receiving them. That would be an important advance, both clinically and from the simple standpoint of scale,” Bhattacharya said. “You wouldn’t have to make individualised therapies for every single person – you can start with one pluripotent stem cell type, turn it into the cell type you want and then give it to almost anyone.”