In Vitro Behaviour of Tissue of Adult Mammalian Central Nervous System

Tissue of the central nervous system of adult rhesus monkeys has been successfully maintained in vitro by a culture technique that had been used for the cultivation of highly differentiated tissues. Neurons and some glial cells survived for 84 days in a chemically-defined, protein-free medium which was formulated in the course of this study. Attempts to Infect motor neurons in Implanted fragments of the anterior horn and cerebral cortex with poliovirus type 1 were unsuccessful. A cell-strain was established from trypsinized adult rhesus monkey cerebral tissue. The cultures, comprising choroid epithelial cells, astrocytes and microglial cells, were maintained in vitro by serial subcultivations. The cells retained their normal karyotype but degenerated after about six weeks. No endogenous virus was detected. The cultures supported the growth of a number of viruses. Echovirus type 11 and Coxsackie viruses types A7 and B3 produced cytopathogenic changes typical of the picornavirus group. Reovirus type 1 produced 1ntracytoplasm1c Inclusion bodies, and giant-cells were formed in monolayers Infected with vaccinia and herpes simplex virus. Vaccinia-infected cells were localised by haemadsorption. Vaccinia virus affected all cell-types Indiscriminately while with the other viruses, the choroid epithelial cells succumbed to Infection before the other cell types. Serological relationship between Coxsackie viruses A7 and B3 was determined by complement-fixation test. Coxsackie A7 antigen cross-reacted with anti-Coxsackie B3 serum, but no reaction was detected between Coxsackie B3 antigen and Coxsackie A7 antiserum. A hypothesis has been postulated for the antigenic structures of the two viruses to explain for this non-reciprocal cross-reaction. The potential usefulness of the newly-described cell strain Includes the study of neurotropic viruses Including the "slow viruses" and the primary Isolation of viruses from clinical materials.