Today, University of Minnesota physicians will perform the world’s first cord blood transplant designed specifically to cure a pediatric patient of HIV/AIDS and acute lymphoblastic leukemia (ALL).
The procedure will take place at the University of Minnesota Medical Center and will be completed by a clinical team composed of transplant physicians Michael Verneris, M.D. and John Wagner, M.D., of the Masonic Cancer Center, University of Minnesota, and HIV/AIDS infectious disease specialist Timothy Schacker, M.D.
The breakthrough nature of the case stems from the use of cord blood (the blood extracted from the placenta after a baby is born) that contains a variant of the cell surface protein CCR5 – known as CCR5Δ32. Present in less than one percent of the population, CCR5Δ32 prevents most strains of the HIV virus from entering a patient’s T cells, ultimately protecting against the destruction of the host’s immune system.
“What we’re attempting is a first and potentially landmark case for the HIV/AIDS community,” said Wagner, an internationally recognized stem cell transplant expert and pioneer in cord blood transplantation at the University of Minnesota. “This now offers patients with HIV and leukemia or lymphoma new hope. But even more importantly, this should compel cord blood banks worldwide to identify how many cord blood units with CCR5Δ32 exist within the inventory. We also hope this case prompts others to find novel ways to block or alter CCR5 to mimic this protective variant.”
To date, the only patient proved cured of HIV/AIDS by such an approach is Timothy Brown, (referred to as “Patient 1” or the “Berlin Patient”), who was treated with bone marrow from a donor with the CCR5Δ32 variant in 2007.
While the approach used in Mr. Brown is curative, finding a bone marrow donor that is both a match for human leukocyte antigens (HLA) and carries the CCR5Δ32 variant has proven nearly impossible for clinical teams worldwide. University of Minnesota researchers are attempting to solve this problem by using umbilical cord blood, which is readily available.
In addition, cord blood, which is collected and banked at the time of birth, requires less HLA matching because of the unique attributes of the newborn immune system. While only a very small proportion of the world’s inventory of cord blood has been tested for CCR5Δ32, the ability to use cord blood has allowed the University of Minnesota team to find a suitable cord blood unit for their patient.
The cord blood unit was secured from M.D. Anderson Cord Blood Bank in Houston, Texas.
“After 7 days of high dose chemotherapy and radiation, our patient – ‘Patient 2’ – will undergo the transplant procedure on Tuesday. The following 100 days will be a high risk period for the patient, as the treatment can damage different organs as well as wipe out the bone marrow, immune system and the leukemia, hopefully”, said Verneris. “At first, the patient will receive antiretroviral drugs to keep his HIV suppressed. But after several weeks to a few months, we will test the patient for evidence of HIV infection and if none is found we will stop the drugs.”
While the procedure is complex, the researchers are confident the University of Minnesota is the ideal site to attempt such a landmark case.
In 1990, Wagner performed the world’s first cord blood transplant for leukemia. In 1999, researchers at the University of Minnesota performed the first double umbilical cord blood transplant and in 2000, performed the first transplant using umbilical cord blood transplant from a donor conceived using pre-implantation genetic testing to ensure a perfect tissue match and freedom by a genetic disease. The University of Minnesota is one of the largest cord blood transplant centers in the world.
“Acute lymphoblastic leukemia is one of the cancers that occurs more frequently in HIV infected people, “ said Schacker. “If successful, the procedure will prove that HIV infection can be cured and point to new areas of research that may one day lead to a cure for all patients with HIV/AIDS.”
The medical team expects to have a full sense of the clinical outcome over the next 100 days.