Inhibition of murine sarcoma virus induced transformation in an adenovirus -- NRK system.

Cell transformation induced by murine sarcoma virus (MSV-M) is significantly inhibited (80--90%) in a clonal line of normal rat kidney (NRK) cells when they are infected with rat cell passaged adenovirus 12 (R-Ad12). No inhibition is seen when R-Ad12 is added simultaneously with, or 1 1/2 or 24 hr after, MSV-M infection, suggesting that inhibition occurs most probably intracellularly. There is also a direct correlation between the extent of focus formation and the concentration of R-Ad12 used. Concentrations of R-Ad12 used to inhibit cell transformation do not affect cell growth. Significant inhibition in foci (90--100%) is also evident in the first two subcultures of R-Ad12 infected NRK cells. The mechanism of the inhibition is not yet known.