Table 2.

Yield of parental and recombinant viruses in the absence of Gua-HCl

100-μl reactions −Gua-HCl	PV1(M)gs (SK-N-MC)			PV1(RIPO)gr (HeLa + Gua-HCl)			Recombinants (SK-N-MC + Gua-HCl)			F
	D	P	T	D	P	T	D	P	T
I	104	18	1.8  ×  105	2.5  ×  103	166	4.1  ×  105	25	2	50	0.8  ×  10−4
II	104	21	2.1  ×  105	2.5  ×  103	140	3.5  ×  105	25	3	75	1.4  ×  10−4
III	104	19	1.9  ×  105	2.5  ×  103	144	3.6  ×  105	25	2	50	0.9  ×  10−4
IV	104	16	1.6  ×  105	2.5  ×  103	128	3.2  ×  105	25	3	75	1.5  ×  10−4
V	104	11	1.1  ×  105	2.5  ×  103	146	3.6  ×  105	25	2	50	1.0  ×  10−4
Avg.			1.7  ×  105			3.6  ×  105			60	1.1  ×  10−4

D, dilution factor; P, no. of plaques; T, titer in pfu/ml; F, frequency of recombination.