Table 6. Frequency of viral-cell junctions and replicative intermediates per transfected cell in serial transfers after transfection.

Transfers (1:10)	Frequency of left junctions	Frequency of right junctions	Frequency of replicative intermediates
0	2.4 × 10-4 (46)*	7.8 × 10-5 (8)	2.3 × 102
1	8.1 × 10-5 (7)	ND	5.0 × 100
2	1.4 × 10-4 (12)	ND	5.5 × 10-1
3	1.8 × 10-4 (15)	ND	1.0 × 10-1
5	3.2 × 10-4 (106)	1.8 × 10-4 (19)	4.9 × 10-3

Transfected cells were assayed for viral-cell junctions and for viral replicative intermediates after the indicated number of transfers and outgrowth of cells. One-tenth of the total cells were subcultured at each transfer. Frequencies are expressed as copies per transfected cell. ND, not determined.

^*Number of viral-cell junctions observed