ANTIBODY PLAQUE FORMATION BY NORMAL MOUSE SPLEEN CELL CULTURES EXPOSED IN VITRO TO RNA FROM IMMUNE MICE.

Suspensions of normal spleen cells from nonimmune mice were treated in vitro with RNA extracted from spleen cells from donor mice immunized 4 days previously with sheep erythrocytes. Subsequent incubation of the RNA-treated cells in tissue culture medium at 37 degrees C for several days resulted in a marked increase in the number of localized zones of hemolysis ("antibody plaques") in relation to the number of viable cells plated in agar containing sheep erythrocytes and complement. Nonimmune cells maintained in tisse, culture medium did not form plaques after incubation with either RNA from Immune mice or ribonuclease-treated RNA from immune mice, or with RNA from non-immune donor mice, or from donors immunized with chicken erythrocytes or bovine serum albumin.