Dr. Tippi MacKenzie

Surviving with Joy

/ Kevin McCormack / 2 Comments
Dr. Tippi MacKenzie (left) of UCSF Benioff Children’s Hospital San Francisco, visits with newborn Elianna and parents Nichelle Obar and Chris Constantino. Photo by Noah Berger

Alpha thalassemia major is, by any stretch of the imagination, a dreadful, heart breaker of a disease. It’s caused by four missing or mutated genes and it almost always leads to a fetus dying before delivery or shortly after birth. Treatments are limited and in the past many parents were told that all they can do is prepare for the worst.

Now, however, there is new hope with new approaches, including one supported by CIRM, helping keep these children alive and giving them a chance at a normal life.

Thalassemias are a group of blood disorders that affect the way the body makes hemoglobin, which helps in carrying oxygen throughout the body. In alpha thalassemia major it’s the lack of alpha globin, a key part of hemoglobin, that causes the problem. Current treatment requires in blood transfusions to the fetus while it is still in the womb, and monthly blood transfusions for life after delivery, or a bone marrow transplant if a suitable donor is identified.

A clinical trial run by University of California San Francisco’s Dr. Tippi MacKenzie – funded by CIRM – is using a slightly different approach. The team takes stem cells from the mother’s bone marrow and then infuses them into the fetus. If accepted by the baby’s bone marrow, these stem cells can then mature into healthy blood cells. The hope is that one day this method will enable children to be born with a healthy blood supply and not need regular transfusions.

Treating these babies, saving their lives, is the focus of a short film from UCSF called “Surviving with Joy”. It’s a testament to the power of medicine, and the courage and resilience of parents who never stopped looking for a way to help their child.

Tissues are optional but advised.

Stem cell transplant in utero offers potential treatment for congenital diseases

/ Yimy Villa / 2 Comments
Dr. Tippi Mackenzie, UCSF
Image Credit: UCSF

Each year, around 24,000 women in the US lose a pregnancy. One reason for this unfortunate occurrence are metabolic disorders, one of which is known as Sly syndrome and is caused by a single genetic mutation. In Sly syndrome, the body’s cells lack an enzyme necessary for proper cell function. Many fetuses with this condition die before birth but those that survive are treated with regular injections of the lacking enzyme. Unfortunately, patients can eventually develop an immune response to these injections and it cannot enter the brain after birth.

However, a team of researchers at UCSF are looking at exploring a potential treatment that could be delivered in-utero. In a CIRM supported study, Dr. Tippi Mackenzie and Dr. Quoc-Hung Nguyen transplanted blood-forming stem cells from normal mice into fetal mice carrying the genetic mutation for Sly syndrome. The researchers were most interested to see whether these cells could reach the brain, and whether they would change into cells called microglia, immune cells that originate from blood-forming stem cells. In a normally developing fetus, once matured, microglia produce and store the necessary enzyme, as well as regulate the immune environment of the brain.

Stem cells transplanted in utero (green) engrafted into fetal mouse brain tissue. 
Image credit: Q-H Nguyen/MacKenzie lab.

The researchers found that the stem cells were able to engraft in the brain, liver, kidney, and other organs. Furthermore, these stem cells were able to eventually turn into the appropriate cell type needed to produce the enzyme in each of the organs.

In a press release, Dr. Mackenzie talks about the impact that this potential treatment could have.

“This group of vulnerable patients has been relatively ignored in the fetal surgery world. We know these patients could potentially benefit from a number of medical therapies. So this is our first foray into treating one of those diseases.”

In the same press release, Dr. Nguyen talks about the impact of the results from this study.

“These exciting findings are just the tip of the iceberg. They open up a whole new approach to treating a range of diseases. At the same time, there’s also a lot of work to do to optimize the treatment for humans.”

The next step for Dr. Mackenzie is to apply to the U.S. Food and Drug Administration to launch a clinical trial of enzyme replacement therapy that will ultimately enroll patients with Sly syndrome and related metabolic disorders.

This approach is similar to a CIRM funded trial conducted by Dr. Mackenzie that involves a blood stem cell transplant in utero.

The full results to this study were published in Science Translational Medicine.

Performance, Passion and Progress: and that’s just page one of our 2018 Annual Report

/ Kevin McCormack / Leave a comment

2018_ar_webimage

It’s hard to sum up the activities and achievements of a year in a single document, let alone one that’s just 24 pages. But that’s what we have done in putting together our 2018 Annual Report.

It’s a look back at the year just gone, the highlights, the low lights (spoiler alert – there weren’t any) and the impact we had on the field of stem cell research. But it’s far more than that. It’s also a look ahead. A look at the challenges we face, and profiles of the people who are going to help us overcome those challenges and maintain our progress.

And people are truly at the heart of this report, from UC San Francisco’s Dr. Tippi MacKenzie who is on the front cover for her work in developing an in-utero treatment for the almost always fatal disorder alpha thalassemia major (and the photo of the baby and mom whose lives were changed by that therapy) to Rich Lajara on the back cover, the first person ever treated in a CIRM-funded clinical trial.

Inside are an array of simple images designed to reflect how we as a state agency have performed this year. The numbers themselves tell a powerful story:

  • 50 clinical trials funded to date, 7 this year alone
  • $2.6 billion in CIRM grants has been leveraged to bring in an additional $3.2 billion in matching funds and investments from other sources.
  • 1,180 patients have been involved in CIRM clinical trials

We know people don’t have a lot of time to read Annual Reports so we have made this as visually engaging and informative as possible. We want you to get a real sense of who we are, what we have done and who has helped us do that without you having to wade through a document the size of War and Peace (great book by the way – the Russians beat Napoleon).

We think we have a great story to tell. This Annual Report is one chapter in that story. We hope you like it.

 

CIRM funded study results in the first ever in utero stem cell transplant to treat alpha thalassemia

/ Pallavi Penumetcha / Leave a comment

Mackenzie

Dr. Tippi MacKenzie (left) of UCSF Benioff Children’s Hospital San Francisco, visits with newborn Elianna and parents Nichelle Obar and Chris Constantino. Photo by Noah Berger

Imagine being able to cure a genetic disorder before a baby is even born. Thanks to a CIRM funded study, what would have been a mere dream a couple of years ago has become a reality.

Drs. Tippi MacKenzie and Juan Gonzalez Velez of the University of California San Francisco (UCSF) have successfully treated alpha thalassemia in Elianna Constantino, using stem cells from her mother’s bone marrow. Alpha thalassemia is part of a group of blood disorders that impairs the body’s ability to produce hemoglobin, the molecule that is responsible for transporting oxygen throughout the body on red blood cells. Present in approximately 5% of the population, alpha thalassemia is particularly prevalent among individuals of Asian heritage. Treatment options for this disease are severely limited, generally requiring multiple rounds of blood transfusions or a bone marrow transplant which requires immunosuppressive therapy. Normally, fetuses die in the womb or the pregnancy is aborted because of the poor prognosis.

The revolutionary treatment pioneered at UCSF involved isolating blood stem cells (cells that are capable of turning into all blood cell types) from the mother’s bone marrow and injecting these cells into Elianna’s bloodstream via the umbilical vein. The doctors were able to observe the development of healthy blood cells in the baby’s blood stream, allowing for efficient oxygen transport throughout the baby’s body. Because the cells were transplanted at the fetal stage, a time when the immune system is not fully developed, there was low risk of rejection and the transplant occurred without aggressive immunosuppressive therapy.

The baby was born healthy earlier this year and has been allowed to return home. While it is still too early to tell how effective this treatment will be in the long term, it is very encouraging that both the mother and baby have endured the treatment thus far.

In a press release, Dr. MacKenzie states:

“Her healthy birth suggests that fetal therapy is a viable option to offer to families with this diagnosis.”

The in utero stem cell transplant was performed as part of a clinical trial conducted at the UCSF Benioff Children’s Hospitals in San Francisco and Oakland. The trial is currently enrolling 10 pregnant women to test the safety and effectiveness of this treatment over a wider population.

If successful, this type of treatment is particularly exciting because it could be expanded to other types of hereditary blood disorders such as sickle cell anemia and hemophilia.