Subacute sclerosing panencephalitis: propagation of measles virus from brain biopsy in tissue culture

Measles virus was propagated in monolayer cultures established from brain tissue of a patient with subacute sclerosing panencephalitis. Syncytial cells were rendered fluorescent with measles specific antiserums only, by means of an indirect technique. The ultrastructural appearance of the microtubular aggregates was identical in brain tissue and in the cultured cells. Fusion experiments produced a cytopathic effect in humnan embryonic kidney and VERO cell cultures. The virus was identified by hemiagglutination-inhibition, but only in the supernatant of disrupted cultured cells.

Stationary phase of cultured mammalian cells (L5178Y)

The stationary phase of the mammalian cells L5178Y in culture can be divided into two stages: (a) an early phase characterized by the decline of mitotic index, followed by a stabilization of the cell number, and (b) a late stage, occurring several hours after the flattening of the growth curve, during which dead or dying cells appear in the cultures. The estimates of rates of cell progress showed that the rates from G(1) to S and from G(2) to M were affected in the early stationary phase. The main cause of cessation of increase in cell number in the early stationary phase is resulted from the decline in mitotic index, which is caused by prolongation of the G(2) period. The importance of the G(2) stage in regulating the cell growth is discussed in relation to other known situations in the literature.