Stem cells and rejection: new clues and possible solutions

Study of the causes of rejection in stem cells transplants: the role of mitochondria in the field of regenerative medicine

Dr. Tobias Deuse and his team of researchers at UC San Francisco Transplant and Stem Cell Immunobiology (TSI) Lab have made another important discovery about the use of induced pluripotent stem cells (iPSCs) in therapeutic transplants.

Focusing for many years on the study of the causes of rejection in iPSC transplants, researchers have identified in the process of conversion from adult cell to stem cell (iPSC) a mutation of the DNA of mitochondria, i.e. small cell structures responsible for cell respiration.

This mutation could cause an immune system response, leading to the rejection of transplanted stem cells: «The role of mitochondria has been largely ignored in the field of regenerative medicine, but earlier efforts in our lab suggested that they may affect the outcome of stem cell transplants,» says Dr. Deuse. «It’s important that we understand their role so that we’re able to reliably quality-control our engineered cells and make sure stem cell products can be transplanted into patients without rejection».

The new study on mitochondrial cells therefore suggests that physicians may need to perform accurate screening for mitochondrial mutations before administering stem cell therapies.

Dr. Deuse and his team have previously published another study in which they describe their innovative method of making iPSC cells “invisible” to the immune system in order to avoid rejection after transplantation. This technique could ensure that treated patients do not reject iPSC and other stem cells with mitochondrial mutations.

The iPSC are produced in the laboratory from adult stem cells that are “reprogrammed” (induced) so that they return to an embryonic state. In this way, reprogrammed cells can be differentiated into any cell type, property for which they are defined as pluripotent.

The umbilical cord stem cells have unique biological and immunological characteristics; their collection is carried out at birth thanks to a simple procedure and without any risk for the mother or the baby. Find out how to store them with Nescens Swiss Stem Cell Science.