Our Platform

Immune Tolerance through Chimerism

The challengechimerism  |  facilitating cells  |  manufacturing process  |  results

Talaris scientists have discovered a way to use the body’s immune system to help it potentially achieve tolerance to both an individual’s own tissues as well as donated organs from another individual.

The Challenge

Scientists have known for decades that bone marrow-derived stem cells from a healthy donor (referred to as an allogeneic stem cell transplant) have the potential to induce durable tolerance both to transplanted organs as well as to an individual’s own tissues. However, the significant risks associated with a conventional stem cell transplant from a donor who is not a perfect immune system match to the recipient, and the unpredictability of achieving durable engraftment of the donor’s stem cells in the recipient, have prevented widespread use. Conventional allogeneic stem cell transplant also brings a risk of graft versus host disease, which is a serious condition whereby the donor’s immune cells attack the recipient’s tissues.

The Promise of Chimerism

FCR001 is designed to promote immune tolerance by inducing chimerism in the recipient’s immune system, while minimizing the risk of graft versus host disease. Chimerism refers to a state where both the donor’s and recipient’s immune cells co-exist durably in the transplant recipient (creating, in effect, a dual immune system in the transplant recipient).

In combination with an organ transplant, a single dose of FCR001 may enable the recipient’s immune system to recognize the donated organ as “self.” This potentially allows the transplant recipient’s immune system to accept the transplanted organ without the need for lifelong immunosuppression.

In the case of certain types of autoimmune or immune-mediated disorders, FCR001 may have the potential to restore self-tolerance to patients who have lost tolerance to some aspect of “self.”

 

“As a transplant surgeon, I have seen firsthand the life-saving benefits of organ transplantation as well as the challenges our patients face due to their lifelong dependence on immunosuppressive drugs.  It has been immensely gratifying to see our research discovery being applied to improve the lives of kidney transplant recipients.”

— Suzanne Ildstad, Founder and Chief Scientific Officer

The Discovery of Facilitating Cells

The Talaris platform technology builds upon our founder Dr. Suzanne Ildstad’s discovery of the Facilitating Cell. These cells exist in the bone marrow and are distinct from stem cells. Pre-clinical research on the Facilitating Cell has shown that they act as nurse cells that nurture stem cells in the bone marrow. After a stem cell transplant, Facilitating Cells help the transplanted stem cells migrate to the recipient’s bone marrow, where they produce immune cells and other blood cells. When combined with other cells through our proprietary process, Facilitating Cells help to promote engraftment of the donor’s cells in the recipient’s bone marrow.

We have also shown that Facilitating Cells help to promote certain types of cells and processes in the recipient that enhance the development of immune tolerance and reduce the risk of graft versus host disease. We have demonstrated that FCR001 allows candidates for bone marrow transplants to receive stem cells safely from unmatched and unrelated donors, with much lower risks than a traditional allogeneic bone marrow transplant.

How FCR001 works

For some scientific publications on Facilitating Cells, click here.

Our Manufacturing Process

Talaris has developed a proprietary process to make FCR001. We rigorously control the product and process at every step of the way, from donor to recipient. The process begins with cells collected from the donor’s blood via a standard mobilization and apheresis procedure, at least a few weeks before the kidney transplant. These cells are shipped to our centralized, cGMP cell processing facility, where highly trained personnel process the donated cells to remove certain potentially harmful cell populations, enrich for stem cells and Facilitating Cells, and then perform a series of analytical studies to confirm the quality of the product. Each FCR001 product is customized to the particular recipient. The final product is frozen and then shipped to the clinical site, where it is stored until it can be administered to the transplant recipient.

 

 

Donor undergoes mobilization and apheresis as an outpatient to collect cells for the Talaris product.
Donor undergoes mobilization and apheresis as an outpatient to collect cells for the Talaris product.
Donor’s cells are refrigerated and shipped to Talaris’ GMP cell processing facility.
Donor’s cells are refrigerated and shipped to Talaris’ GMP cell processing facility.
Highly trained manufacturing team utilizes proprietary Talaris technology to remove certain types of undesirable cells and enrich the  product for stem cells and facilitating cells.
Highly trained manufacturing team utilizes proprietary Talaris technology to remove certain types of undesirable cells and enrich the product for stem cells and facilitating cells.
Final product is frozen and shipped to the clinical site, where it can be stored until needed.
Final product is frozen and shipped to the clinical site, where it can be stored until needed.

Our Phase 2 Results

Talaris has followed the patients in our Phase 2 study for an average of over 4.5 years, and for as long as 9 years. Our data indicate the potential of successfully tolerized transplant patients to remain off chronic immunosuppression durably without rejecting their organ.

We believe that our technology has the potential to benefit patients in other transplant settings as well as patients who suffer from difficult-to-treat auto-immune diseases or immune-mediated diseases. Click here for a link to our pipeline.