Shawn Cain

An artificial liver support system is described herein which comprises cryopreserved hepatocytes having an initial viability of 80-99%. Further disclosed are hepatocytes cryopreserved by dispensing hepatocytes into freezing containers, freezing the containers from between minus 50 to minus 90 degrees Celsius, storing the containers in liquid or vapor nitrogen, thawing the cryopreserved hepatocytes when ready for use and removing residual cryoprotectant media.

The invention relates to a method of removing an agent from a suspension of cells using a semi-permeable membrane. In one aspect of the invention, the cells are used to bioprocess a biological fluid after removal of the agent.

The invention is based in part on the observation that significant portions of porcine livers appear to remain intact after perfusion by standard methods, suggesting that the perfusion procedures employed do not result in complete enzymatic digestion. Recovery of cells is therefore substantially lower than would be possible if the organs were thoroughly digested. It is found that increased perfusion flow rate, occlusion of at least one major blood vessel leading out of the organ, increased… Show more

The invention is based in part on the observation that significant portions of porcine livers appear to remain intact after perfusion by standard methods, suggesting that the perfusion procedures employed do not result in complete enzymatic digestion. Recovery of cells is therefore substantially lower than would be possible if the organs were thoroughly digested. It is found that increased perfusion flow rate, occlusion of at least one major blood vessel leading out of the organ, increased enzymatic digestion time, and vigorous tissue dissociation techniques can be combined to afford a uniquely high yield of viable cells. Show less

The invention features a method of processing cryopreserved cells by thawing and equilibrating the cells at warm temperatures (e.g., between 30.degree. C. and 43.degree. C). Either the cell suspension in the cryoprotective medium is thawed to a temperature between 35.degree. C. and 43.degree. C. or the cryoprotective medium is equilibrated with a culture medium at a temperature between 35.degree. C. and 43.degree. C., or both steps are carried out at the warm temperatures. By thawing and… Show more

The invention features a method of processing cryopreserved cells by thawing and equilibrating the cells at warm temperatures (e.g., between 30.degree. C. and 43.degree. C). Either the cell suspension in the cryoprotective medium is thawed to a temperature between 35.degree. C. and 43.degree. C. or the cryoprotective medium is equilibrated with a culture medium at a temperature between 35.degree. C. and 43.degree. C., or both steps are carried out at the warm temperatures. By thawing and equilibrating the cryopreserved cells at warm temperatures, the viability, (especially after 3 hours of culture), and metabolic activity (i.e., diazepam metabolism) of the cells can be improved over traditional cold cell processing (i.e., at temperatures of between 2.degree. C. and 8.degree. C.).
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The invention features a method of processing cells in a closed system that results in a suspension of cells in a transfer vessel containing a target number of cells. The number of cells in the closed vessel is determined from the cell concentration (i.e., the number of viable cells/mL) in the closed vessel and the total volume of the suspension in the closed vessel. The volume of the suspension in the closed vessel can be determined from the weight of the suspension and its density. In… Show more

The invention features a method of processing cells in a closed system that results in a suspension of cells in a transfer vessel containing a target number of cells. The number of cells in the closed vessel is determined from the cell concentration (i.e., the number of viable cells/mL) in the closed vessel and the total volume of the suspension in the closed vessel. The volume of the suspension in the closed vessel can be determined from the weight of the suspension and its density. In particular, the cells are preserved in a protective medium and are recovered substantially free of the protective medium in a closed vessel containing the known number of cells in a suspension. Show less

An artificial liver support system is described herein which comprises cryopreserved hepatocytes having an initial viability of 80-99% and a metabolic activity 50-80% of fresh hepatocytes. Further disclosed are hepatocytes cryopreserved by dispensing hepatocytes into freezing containers, freezing the containers from between minus 50 to minus 90 degrees Celsius, storing the containers in liquid or vapor nitrogen, thawing the cryopreserved hepatocytes when ready for use and removing residual… Show more

An artificial liver support system is described herein which comprises cryopreserved hepatocytes having an initial viability of 80-99% and a metabolic activity 50-80% of fresh hepatocytes. Further disclosed are hepatocytes cryopreserved by dispensing hepatocytes into freezing containers, freezing the containers from between minus 50 to minus 90 degrees Celsius, storing the containers in liquid or vapor nitrogen, thawing the cryopreserved hepatocytes when ready for use and removing residual cryoprotectant media. Show less