Abstract: Disclosed is a process for damage-free encapsulation of a variety of core materials including viable cells. The core material is suspended in an aqueous solution of a polymeric material containing cationic groups such as an aminated glucopolysaccharide, e.g. chitosan. A temporary matrix is formed by gelling droplets of the suspension with a divalent or multivalent anion. The temporary matrix is permanently cross-linked with a polymeric material containing plural anionic groups, e.g., polyaspartic or polyglutamic acid, to form a semipermeable membrane. The interior of the microcapsule may be resolublized by subjecting the capsule to a solution of low molecular weight cations. The process produces microcapsules which are not sticky, do not clump and allow viable cell growth and proliferation.

Abstract: Cells such as genetically modified cells, e.g., hybridoma, which secrete an antigenic substance are encapsulated within capsule membranes having pores of dimensions sufficient to permit efflux of the antigens secreted by the cells but insufficient to permit traverse of the cells. The capsules are injected into an experimental animal where antigen passing through the pores of the capsule membrane induces lymphocytes to produce antibodies complementary to the antigen. The antibody may be harvested from the circulatory system of the animal. Preferably, lymphocytes are sampled from, e.g., the spleen of the animal, fused with a malignant cell line to produce a hybridoma which synthesizes the antibody in vivo, and the hybridoma is cultured to produce large quantities of monoclonal antibody.

Abstract: Disclosed is a new material having antiviral activity designated interferon epsilon. The material may be produced, for example, by exposing primary, diploid human epithelial cells to a virus and then incubating the cells under conditions in which the new interferon is produced and is secreted into the culture medium. The material is antigenically distinct from interferon alpha, interferon beta, and interferon gamma, and displays marked antiviral activity in human epithelial cells but no detectable activity in other cell types.

Abstract: Disclosed is a process for recovering nonsecreted substances produced by cells. The process eliminates some of the high molecular weight contaminants thereby simplifying the purification process. The cells are encapsulated within a semipermeable membrane having properties which permit rapid passage of the relatively low molecular weight substances of interest but retard or prevent passage of higher molecular weight contaminants. The encapsulated cells are suspended in a culture medium and undergo normal cell growth and mitosis. The encapsulated cell culture grows to substantially fill the capsules but not rupture them. The cell membrane is then lysed without disrupting the capsule membrane. The permeability of the capsule membrane is such that the substances of interest diffuse rapidly through the capsule membrane into the extracapsular fluid while the higher molecular weight contaminants and cell fragments are retained within the capsule.

Abstract: Disclosed is a method of growing anchorage-dependent cells: cells of the type which normally undergo mitosis only when anchored on a substrate, e.g., fibroblasts or epithelial cells. The method comprises the steps of encapsulating a seed culture of the cells within a semipermeable membrane and suspending the capsules in a growth medium. The interior surfaces of the capsule membrane and/or collagen enclosed within the capsules serve as a substrate for the cells. The ratio of the available substrate surface area to the volume of the culture may be large, thereby allowing the cells to be grown substantially throughout the volume of the culture medium.