A mother of two beautiful children, Lucie Clark was diagnosed with multiple sclerosis while she was slowing losing her eyesight and ability to walk.
From the umbilical cord to the cryo-preserver – Part 2
In this multi-part series we will capture the journey of your baby’s precious stem cells from the time it reaches our lab, till it gets into the cyro-cylinder.
Sample Processing – Extracting the stem cells from the samples
In the earlier post, we explored the series of steps involved in receipt of the sample at LifeCell and how it gets prepared for its journey through the lab. In this part, we will discover how stem cells are extracted from the samples that came from the hospital and how they go into the cyro-cylinders.
Preparing the processing room
At the sample receipt area, the lab ID is stuck on the outer carton of the samples. These are placed inside the cold room to be moved to the processing area. At the processing lab, the technician receives the sample from the cold room and readies the materials required for processing of the samples including syringes, transfer bags, alcohol swabs, vaccutainers, etc are available in the processing kit-box.
”We have 3 shifts per day. Each shift sees 4-5 technicians who together process an average of 60 samples per shift” says Muthuraman, Manager, Cord Blood Processing at LifeCell. “Once the technicians are in, they begin their shift by maintenance of the equipments to ensure the area is sterile” Muthuraman adds. The equipments including the centrifuge, the weighing balance are cleaned with alcohol. The Laminar Air Flow – the cabinet where the technician works is enabled with UV which is turned on to sterilize the area.
Customized processing technique
At LifeCell, the stem cell processing is customized based on the volume of the sample – known as LifeCell’s Proprietary Personalized Processing. The methods differ in the way the samples are centrifuged and the stem cells are separated. Both methods ensure maximum stem cell extraction and minimum presence of RBCs.
First, 0.5 ml of pre-sample is taken and sent to the Quality Control department to check the count of the stem cells present in the sample prior to processing. This is to determine the retrieval percentage at the end of processing.
Separating the stem cells
To begin with the processing, the chemical Hespan is added to deplete the Red Blood Cells in the sample. The sample is then spun at high speed using a special centrifuge. The sample is now split into three portions – plasma, the buffy coat and the Red Blood Cells. The plasma, and the buffy coat that contains the stem cells are then transferred to another bag. The plasma and the buffy coat are then spun once again at high speed. Now the buffy coat that contains the stem cells settle down and the plasma is expressed out using special equipment. From the buffy coat that is finally retained, 0.5 ml is sent to the Quality Control department to check the count of stem cells present in the sample post processing.
A special cryo-preservative, DMSO-Dextran that protects the stem cells from the low temperatures is added. The sample is transferred to a special cryo-bag which is segmented as the main bag and pilot bag. For clients who opt for dual storage, the pilot bag is separated from the main bag and sent to our secondary facility at Gurgaon. The sample transferred to the cryo-bag also fills in other segments that are in the form of tubes, integrally attached to the cryo-bag. These are meant for sample testing for Quality Control and HLA matching parameters.
Preservation: Samples into the cryo-cylinder
The bags are placed within Aluminium canisters and kept within the Controlled Rate Freezer which gradually brings down the temperature from room temperature to -196 degrees. The canisters are then lowered into the cryo-cylinders for long term storage. In the next post we will find out the battery of tests that the samples are run through to check for the presence of infections and determine the count of stem cells.