Table 2.

Number of predicted copies of integrated vectors in the analyzed samples

Block	DNA, ng	Diploid genomes corresponding to inputa	Tumor cells (%)b	VCNc	Random integrationd			Clonal integratione
					1.00%	0.10%	0.01%
A3	45	6,300	50%	1	31.5	3.15	0.315	3,150
B1	57	7,980	25%	1	19.95	1.995	0.1995	1,995
C1	5	700	75%	1	5.25	0.525	0.0525	525

AAV, adeno-associated virus; H&E, hematoxylin and eosin; LOD, limit of detection; VCN, vector copy number. Example for block A3: 45 ng of DNA corresponded to 6,300 cells (because each human cell contains ∼7.2 pg of DNA). Assuming that 50% of this sample contains tumor cells (as suggested by ISH) and has a VCN of 1, and assuming that integration happens randomly in 1% of the tumor cells, 31 different copies of integrated vector could be expected in the sample. This is likely below the LOD, especially if the integration rate was 0.1% or 0.01%. However, if all cells were derived from the same integrated clone, then 3,150 integrated vector copies (i.e., with the same integration site) would be expected. This is likely above the LOD.

^aAverage weight of DNA contained in one human diploid genome is 7.2 pg.

^bPercentage tumor cells in sample estimated on H&E-stained serial sections.

^cEstimated VCN vector copy number in tumor cells based on in situ hybridization.

^dRate of random integration per VCN from published literature.^8,37,38,39

^ePredicted AAV vector sequence number if clonal integration present in tumor cells.