Abstract: 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.

Abstract: 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.).

Abstract: A device which serves as an artificial pancreas comprises a hollow fiber having an inner diameter of about 5 mm which is surrounded by islets of Langerhans enclosed in a housing. The islets are suspended in a semi-solid matrix which ensures desired distribution of the cells about the hollow fiber. The hollow fiber and suspended islets are enclosed in a housing which further aids the desired distribution of islets about the hollow fiber. The hollow fiber has a porosity which selectively allows passage of substances having a molecular weight of less than about 100,000 Daltons. The semi-solid matrix in which the islets are embedded and suspended is formed of an appropriate supporting material such as alginate or agar.