Lyophilized heparin demonstrates better ability to preserve cord blood stem cells than CPD: Study

Lyophilized heparin, a proprietary anticoagulant developed specifically for cord blood collection, demonstrated a better ability to preserve the number of viable cells over a longer period of time than a commonly-used anticoagulant, citrate phosphate dextrose (CPD), according to a study presented today at the International Society for Cellular Therapy (ISCT) Annual Meeting.  

"Clinical research has shown that stem cell count is an important factor that can affect treatment outcomes," said Heather Brown, MS, CGC, vice president of scientific & medical affairs at CBR and one of the study authors. "When collecting cord blood, the goal is to save as many stem cells as possible.  Our study demonstrates that using collection bags with lyophilized heparin can result in more viable cells available for storage and medical use."

Once collected, cord blood has a tendency to coagulate – or form clots – which can interfere with stem cell processing and preservation.  To prevent clotting, cord blood collection devices are pre-loaded with an anticoagulant.  Citrate phosphate dextrose (CPD) has been commercially-available for decades. It was originally developed to extend the shelf life of red blood cells collected for use in blood transfusion therapies for patients with severe blood loss or anemia.  However, red blood cells are typically discarded in the process of preserving cord blood stem cells.  Lyophilized heparin was developed by Cord Blood Registry, the world's largest stem cell bank, in an effort to increase the number of cord blood stem cells viable for preservation.

The study objective was to evaluate how both the type of anticoagulant used and the transit time (from hospital to processing laboratory) impact cord blood stem cell viability and concentration.  The results show that cord blood collections with lyophilized heparin maintained cell viability and concentration regardless of transit time; however, the cell populations in CPD collections were adversely impacted 36 hours after collection, showing significantly lower viability and cell concentration.

Umbilical cord blood collections with CPD or lyophilized heparin were matched for blood volume and then categorized according to transit time: those arriving less than 24 hours, between 24 to 36 hours, or greater than 36 hours after collection to CBR's stem cell processing facility. The cell counts were then assessed in each sample by two measures – total nucleated cell (TNC) count and mononuclear cell (MNC) count – both of which are used to predict the time to engraftment as well as transplant survival rates.  The TNC count is considered a standard measure since it is easily reproduced across laboratories and readily available, whereas the MNC count is believed to better reflect the potency of the sample as well as better predict transplant outcomes.

Beyond its efficacy, lyophilized heparin has been proven to be a safe anticoagulant. Heparin is a naturally-occurring substance in the human body.  Because of its broad use in a number of medical procedures, more than one billion doses of therapeutic heparin are produced annually.

"CBR invested significant resources and many years in the development of lyophilized heparin because we recognized the limitations of CPD for cord blood collection," said Brown.  "Expecting parents who have decided to preserve their newborn's stem cells should know that the cord blood collection technology offered by CBR is unique and can deliver a better result."