FIG. 1.

JSRV pseudotype vector transduction rate is not decreased by prior incubation with Survanta. SSF and HT-1080 cells were plated at 10⁵ cells per 3.5-cm-diameter well of six-well plates. Both cell types were grown in Dulbecco's modified Eagle medium with 10% fetal bovine serum in a 10% CO₂–air atmosphere. One day later, LAPSN vectors produced from PJ4 (JSRV pseudotype) or PA317 (amphotropic pseudotype) packaging cells were incubated with various concentrations of Survanta for 30 min at room temperature. The target cells were fed 2 ml of medium containing 5 μg of Polybrene per ml, and portions of the vector-Survanta mixtures were added. SSF cells were used as targets for JSRV vector transduction, and HT-1080 cells were used for the amphotropic vector. At the dilutions used, Survanta had no apparent effect on the health or growth rate of the cells. Three days after vector exposure, the cells were fixed and stained for alkaline phosphatase-positive foci. Means and standard deviations are shown from four experiments for the JSRV vector and from two experiments for the amphotropic vector.