Newswise — Could the answer to repairing the ailing placenta in preeclampsia lie within the stem cells of a healthy placenta? New promising evidence may lead scientists to answer that question. According to findings from an early preclinical study led by Brett Mitchell, PhD, an Associate Professor of Internal Medicine in the Cardiovascular Research Institute (CVRI) at Texas A&M University College of Medicine, there is evidence that administrating placenta-derived cells may help reverse the symptoms associated with preeclampsia in a matter of days after dosing with no harmful effects to mother or baby.
According to The Preeclampsia Foundation, preeclampsia is a condition unique to human pregnancy. It is diagnosed by the elevation of the expectant mother’s blood pressure, usually after the 20th week of pregnancy, combined with the appearance of excessive protein in her urine. Preeclampsia and related hypertensive disorders of pregnancy impact 6-8% of all births in the United States.
The syndrome is comprised of the physical signs of high blood pressure and proteinuria (protein in the urine). Splenomegaly (enlarged spleen) is also commonly found but its presence is not needed for the diagnosis. Preeclampsia involves a shift from protecting the mother and fetus as immune privileged sites to a destructive response that includes an increase in endothelial dysfunction (the inability of blood vessels to relax or dilate).
Dr. Mitchell has devoted many years of his research on diseases characterized by endothelial dysfunction with a particular focus on preeclampsia/gestational hypertension. His research has included examining the immune cells responsible for the development of hypertension during pregnancy in an effort to develop novel therapies that deplete detrimental immune cells while sparing beneficial immune cells.
In this particular study, his team delivered a dose of a special proprietary technology of placenta-based cells called PLX (PLacental eXpanded) cells into the right leg muscle of mice who had preeclampsia. The PLX cells were created and patented by Israeli-based Pluristem Therapeutics Inc., a leading developer of placenta-based cell therapies. PLX cells are a drug delivery platform that releases a cocktail of therapeutic proteins in response to a host of local and systemic inflammatory and ischemic diseases. PLX cells are grown using Pluristem's proprietary 3D micro-environmental technology and are an "off-the-shelf" product that requires no tissue matching prior to administration. After testing 8 groups of 2 separate animal models of preeclampsia, Dr. Mitchell’s team found that PLX cells were indeed effective in treating preeclampsia in their animal models.
The Texas A&M College of Medicine research team began the research by inducing preeclampsia in pregnant (C57Bl/6J) mice that were then given either PLX cells or plasmalyte as a control intramuscularly (IM) one day after inducement. After 3-4 days, they observed positive findings in those animals induced to have preeclampsia and given PLX cells. They observed the following:
• • A progressive, significant (p<0.05) reduction of systolic blood pressure to the level of normal pregnant mice within 3 days of PLX cell administration. Additionally, PLX cells had no effect on blood pressure when given to normal pregnant mice.
• • Significant (p<0.05) reduction of urinary protein excretion to levels seen in normal pregnant mice within 4 days after PLX cell administration. Additionally, PLX cells had no effect on urinary protein excretion when given to normal pregnant mice.
• • Significant (p<0.05) increase in endothelial function (as measured by acetylcholine-induced relaxation) to levels seen in normal pregnant mice within 4 days following PLX cell administration.
• • Significant (p<0.05) reduction in the weight of the spleen to levels seen in normal pregnant mice within 4 days following PLX cell administration. Additionally, PLX cells did not increase the spleen size in pregnant mice demonstrating the lack of immunogenicity of these cells.
• • No significant differences in the number of pups per litter or fetal demise per litter was observed for all groups suggesting PLX cells do not harm the fetus.
Dr. Mitchell and his team will pursue further testing on the use of PLX cells to treat preeclampsia. He will be presenting their initial findings at the Society for Gynecologic Investigation (SGI) Summit in Jerusalem on May 30, 2013. Dr. Mitchell stated, “We were pleasantly surprised that a one-time treatment with PLX cells during pregnancy was able to safely and effectively normalize blood pressure and kidney function in mice with experimental preeclampsia. Our preliminary results suggest that the factors secreted by these cells were able to reduce inflammation and restore endothelial function all while having no deleterious effects on the mother or the fetuses. Since there are currently no treatments for preeclampsia we are hopeful that women with PE will soon benefit from this promising cell therapy.”
Pluristem Therapeutics’ Chairman and CEO, Zami Aberman stated, “While specific mechanisms remain to be determined, this preliminary data demonstrating that Pluristem’s PLX cells are a potential novel therapeutic for the treatment of preeclampsia is very exciting. We look forward to continuing our research with a goal to enter the clinic as soon as possible for this common, potentially lethal disease that currently has no acceptable treatment.”
For more information, log on to www.pluristem.com