Goal 2: Reduce Human Disease

Stem Cell Immunology

We now can create critical cell types like cardiomyocytes etc. from stem cells. Additionally, we are learning the rules of using these cells to rebuild tissues. A major gap in our knowledge relates to the immunobiology of these cells. Lessons from transplantation medicine are only partially applicable, because solid organs are more complex and likely more immunogenic than defined cell populations.


How does the immune system respond to allogeneic cells like cardiomyocytes? If they are rejected, is this through class I or class II MHC? Cell-mediated or humoral immunity? How important are minor (non-MHC) antigens? What class of immunosuppressants are required to prevent rejection? How does this compare to whole-organ tranplants?

Is this idea a Compelling Question (CQ) or Critical Challenge (CC)? Compelling Question (CQ)

Details on the impact of addressing this CQ or CC

We now can generate large quantities of critical cell types whose deficiencies underlie many chronic diseases like heart failure. This breakthrough brings us to the next-level impediment: the immune system. While induced pluripotent stem cells have the potential to obviate rejection, in practical terms this is cost-prohibitive: It will cost huge amounts of money to produce and qualify a single patient's cell dose. Moreover, human cardiomyocytes are potent when given to infarcted hearts in the acute or sub-acute phase of infarction, but they have no benefit with chronic heart failure. The 6 months required to produce iPSC-cardiomyocytes precludes their autologous use for myocardial infarction.

We need an off the shelf cell therapy product for myocardial infarction that can be mass produced and qualified for large numbers of patients. This means an allogeneic product is necessary. Identifying the immune response to cardiomyocytes or other cell products will teach us how to precisely immunosuppress the patient, thereby minimizing complications, or alternatively, how to engineer the cells so as to avoid immunogenicity in the first place.

Lessons from the study of cardiomyocyte transplantation could extend to dopamine neurons, pancreatic beta-cells, retinal cells, myelinating cells and many other areas that cause common chronic disease.

Feasibility and challenges of addressing this CQ or CC

We know a great deal of transplant immunology from hematopoietic stem cell transplantation (graft versus host) and from solid organ transplantation (host versus graft). There are good mouse and large animal (including non-human primate) models of stem cell differentiation and organ transplantation. This offers low hanging fruit where, in perhaps 5 years, we could discern the critical similarities and differences between transplanting stem cell derivatives and organ or marrow transplantation. These studies will inform clinical trials of allogeneic human stem cell derivatives that will be underway by then.

Success in this area will require bringing together researchers interested in stem cell biology and transplant immunology. A properly resourced RFA from NIH could be just the thing needed to promote this interaction.

Name of idea submitter and other team members who worked on this idea Charles Murry, MD, PhD



23 net votes
45 up votes
22 down votes
Idea No. 433