Patrick McGeer
University of British Columbia researchers have discovered a potential new treatment for a rare blood cancer that may also point the way to treating other more common diseases.
Paroxysmal nocturnal hemoglobinemia (PNH) is characterized by episodic rupture of red blood cells and the danger of blood clots forming in the vascular system. The condition results in red blood cells becoming vulnerable to attacks by the body’s own complement immune system and can lead to complications such as anemia, kidney disease and fatal thromboses.
The condition is caused by a genetic mutation that leaves cells deficient in two critical proteins – called protectin and decay accelerating factor – that in healthy individuals shield the red blood cells from self-attack by the complement system.
In a clinical study published today in PLOS ONE, the UBC team, led by Patrick McGeer, a Professor Emeritus in the Department of Psychiatry, applied aurin tricarboxylic acid (ATA), a non-toxic drug, to blood samples of five patients with PNH who were undergoing standard treatment with antibodies administered through biweekly infusions. ATA blocks this self-attack and thus compensating for this deficiency.
The researchers found the addition of ATA, which blocks the self-attack and thus compensates for the protein deficiency, restoring blood cell resistance; antibodies alone did not offer full protection. The team — which also includes Clinical Assistant Professor Sujaatha Nariyanan in the Division of Hematology, and Professor Emerita Edith McGeer and Research Associate Moonhee Lee in the Department of Psychiatry — is now proceeding with further testing, hoping to bring the treatment to clinics within a year.
“Our study suggests that ATA could offer more complete protection as an oral treatment for PNH while eliminating the need for infusions,” says Dr. McGeer, of the Kinsmen Laboratory of Neurological Research. “PNH is a disease that may happen to anyone through a chance mutation, and if nature were to design a perfect fix for this mutation, it would be ATA.”
Dr. McGeer adds that since many diseases are caused or worsened by an overactive complement immune system, the discovery of ATA’s effectiveness in this rare disease could have wide-reaching implications for conditions such as Alzheimer’s and Parkinson disease, macular degeneration, ALS, multiple sclerosis and rheumatoid arthritis.