These are blurry terms. I don't think people use them very precisely. They often mean the same thing.
Anyway, if you want to be formally correct, I guess engraftment is when your cells home to wherever they're supposed to go, e.g. the bone marrow, and then do what they're supposed to do, e.g mature into blood cells. A progenitor cell with limited proliferative potential can engraft.
Repopulation is when you wiped out the bone-marrow, and the animal is bound to die. Then you put stem cells there, and they will first engraft, and then actually multiply and fill the bone-marrow back up with cells ("repopulate" it), and resume normal, permanent blood production. Only a stem cell with self-renewal, and very large proliferative potential can repopulate.
Thanks for the nice explanation. I would like to elaborate my earlier question here: We are doing xeno liver cell transplantation expt in nude mice. We have quantified and calculated percentage for the number of human cells present in mice livers after 4 weeks of transplantation. My question is should we call it as engraftment percentage or repopulation percentage ?
so my question is if we say it as engraftment percentage then we cant compare with other engraftment percentage by other groups since the number will vary with the sample retrieval time.
I think it depends on the context imho. We transplant stem cells of various types into the brain after stroke. For us, I'd call engraftment simply putting any exogenous cell type into the tissue. Repopulation would be more specific than engraftment because it would imply replacing cells that were lost with cells of the same phenotype. My 2 cents.
I do not see the difference. If you have a malfunctioning tissue it can either be caused by cells missing due to specific targeted destruction, or a by a general destruction. If you believe that remaining signaling proteins in the ECM could "home" the cells needed, there is really no difference. The "homing" signal comes from the matrix proteins, either called repopulation or engraftment. If we want to differentiate between these entities, I would define engraftment the process of producing more than the original blueprint.
- Badges
- Science topic
- Similar topics
- Biological Science
- Immunology