Tissue culture of bovine subcommissural organ.

Tissue of the secretory, glial subcommissural organ (SCO) of adult, male cattle was cultured in serum-free medium for 70 days in vitro. Only minor alterations in the histoarchitecture and the cytology of the explanted SCOs could be observed by light and electron microscopy. Light- and electron-microscopic immunocytochemical investigations with an antiserum raised against bovine SCO secretory proteins revealed intra- and extra-cellularly localized immunoreactive material in tissue sections of SCO explants cultured up to 69 days in vitro. An indirect competition enzyme-linked immunosorbent assay (ELISA) was developed to detect minor quantities of SCO secretory products. By means of this assay, approximately 35 ng RF protein per ml was detected in culture medium supernatants conditioned for 3 days in SCO tissue cultures at 3, 38, and 69 days in vitro. These studies demonstrate that the bovine SCO can maintain its secretory activity throughout long periods in vitro.