After the Kit is received, the integrity and identification of the collecting bag is checked by a Cytothera technician. If everything is ok, the Kit is then processed.

 

At the onset of processing, a sampling takes place to determine the number of stem cells as well as to determine cellular viability. This procedure allows for the determination of the number of white blood cells, mononuclear cells and CD34+ cells.

The collecting bag is never opened during processing and in this way, the risk of contamination is kept to a minimum. After sampling analysis, the remaining blood is immediately processed in order to separate the stem cells.

 

The separation of stem cells starts with the removal of red blood cells and plasma, thus reducing the amount of material to store. This reduction process also permits the use of smaller amounts of cryoprotectant (DMSO), thus reducing the probability of secondary effects (nausea and dizziness) commonly associated with DMSO, in case of transplant.

Red blood cells and plasma are removed by centrifugation, permitting the isolation of stem cells with an approximate volume of 20ml and containing between 70 and 95% of the initial mononuclear cells.

Removed red blood cells and plasma are then destroyed by incineration.

 

Before cryopreservation, a cryoprotectant is added to the stem cells. This prevents the loss of cellular viability during freezing and subsequent thawing. The process occurs at a controlled speed, with agitation and progressive temperature dropping (from room temperature to 5ºC).

Samples are then taken for new tests that determine asepsia as well as the number of total and mononuclear cells. The values obtained allow for an evaluation of the success of the whole process.

After sampling, each unit is placed in a cryopreservation tank that reduces the temperature at a controlled rate (Controlled Rate Freezer). This equipment permits cooling of the sample from 5ºC to -140ºC. The controlled drop in temperature diminishes the risk of cell viability loss because it prevents the formation of crystals inside these cells.

When the sample reaches -140ºC, it is removed from the Controlled Rate Freezer and placed in a cryopreservation system where it is stored for a period of 25 years or until it is solicited by the client.