| 20 Mars 2012
Significantly improved cardiac function, smaller infarct size with greater regional left ventricle wall thickness and the pronounced stimulation of new vessels formation were observed in animals treated with PLX cells
HAIFA, ISRAEL, March 20, 2012 -- Pluristem Therapeutics, Inc. (NASDAQ:PSTI; TASE: PLTR) today announced that its PLacental eXpanded (PLX) cells, tested in a preclinical animal model of acute myocardial infarction (AMI), proved to effectively improve several cardiac hemodynamic parameters in animals that received those cells. The study was conducted in collaboration with Professor Christof Stamm, MD and Professor Carsten Tschöpe MD and their respective staffs at the Center for Regenerative Therapies (BCRT), Berlin, Germany.
Twenty mice suffered an AMI by ligating the left anterior descending (LAD) coronary artery via thoracotomy. Immediately following the AMI, animals were given either PLX cells (n=10) or cell-free medium as a control (n=10) into the border zone of the infarct. Additionally, five animals underwent a sham (placebo) operation by incurring the thoracotomy but without ligation of the LAD.
After 4 weeks, transthoracic echocardiography was performed, the mice were sacrificed and their hearts examined histologically. Hemodynamic studies demonstrated improved cardiac contractile function in the mice which received the PLX cells as compared to control-treated mice. The improved cardiac contractile function included a statistically significant increase in stroke volume (p=0.01) (fig. 1) and ejection fraction (p=0.06) (fig. 2).
Fig.1: Stroke volume Fig. 2: Ejection fraction
Additionally, PLX cell-treated hearts had significantly smaller infarct sizes (p=0.04) and greater regional Left Ventricular (LV) wall thickness (fig. 3)
Fig. 3: Infarct size significantly smaller in those animals treated with PLX cells (frame A) versus controls (frame B). No AMI occurred in sham animals (frame C). Infarct size quantified by computerized planimetry on Masson's trichrome stained myocardial sections. The percentage of infarcted myocardium calculated with respect to the entire area of LV myocardium (frame D)
Histological analysis indicated that those animals treated with PLX cells displayed a statistically significant higher number of mature arterial vessels in the infarct border zone than in control animals (p=0.004) and suggests that PLX cells induce the formation of new blood vessels into ischemic myocardium (fig. 4)
Fig 4: Micro-vessel density in the peri-infarct myocardium represented by immunohistology for CD31. Comparison of micro-vessel density between experimental groups. Original magnification 20x. HPF= high power field.
The New England Journal of Medicine reported that approximately 624,000 patients suffer an Acute Myocardial Infarction (AMI) annually in the USA (N Engl J Med 2010;362:2155-65), a number that will most likely increase with the rising prevalence of obesity, diabetes and the aging of the population.
"As a cardiac surgeon, the unique ability demonstrated by Pluristem's PLX cells for the treatment of heart disease is very exciting," said Professor Stamm. "Currently, millions of patients worldwide suffer from cardiac ischemia and physicians are looking for new therapies to treat those patients. PLX cells showed promising results in the AMI studies."
"These results demonstrate the potential benefits of our cells for use in the treatment of ischemic heart disease, a multi-billion dollar annual market, and one in which many pharmaceutical companies are constantly looking to provide patients with innovative and effective solutions,” said Zami Aberman, Chairman and CEO of Pluristem. "In addition to moving ahead with our AMI trial, we look forward to continuing to work on finding cell therapy solutions for numerous debilitating diseases."
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About Pluristem Therapeutics
Pluristem Therapeutics Inc. (NasdaqCM: PSTI; TASE: PLTR) is a leading developer of placenta-based cell therapies. The company's patented PLX (PLacental eXpanded) cells drug delivery platform releases a cocktail of therapeutic proteins in response to a variety of local and systemic inflammatory diseases. PLX cells are grown using the company’s proprietary 3D micro-environmental technology and are an off-the-shelf product that requires no tissue matching or immune-suppression treatment prior to administration.
Data from two Phase I clinical trials indicate that Pluristem’s first PLX product, PLX-PAD, is safe and potentially effective for the treatment of end stage PAD. Pluristem’s pre-clinical animal models have demonstrated PLX cells are also potentially effective in nerve pain and muscle damage when administered locally and in inflammatory bowel disease, MS and stroke when administered systemically.
Pluristem has a strong patent portfolio, company-owned GMP certified manufacturing and research facilities, strategic relationships with major research institutions and a seasoned management team. For more information visit www.pluristem.com, the content of which is not part of this press release. Follow Pluristem on Twitter @Pluristem.
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