Table 1.

β-Gal Staining and Activity in Tissues Harvested Seven Days after the Initial Injection of rAd-lacZ in Newborn and Adult C57BL6/J Mice

# of mice	age	% β-gal staining ( positive cells per high power field)
		Heart	Lung	Intestine	Kidney	Liver
A. β-gal staining
11	newborn	32 ± 13	38 ± 6	37 ± 16	37 ± 8	92 ± 7
10	adult	Non detectable	Non detectable	Non detectable	35 ± 12	95 ± 6
B. β-gal activity in tissue homogenates
6	newborn	5.4 ± 1.1	1.3 ± 0.6	0.18 ± 0.05	1.46 ± 0.56	12 ± 2.4
6	adult	0.45 ± 0.04	0.09 ± 0.05	0.08 ± 0.03	1.44 ± 0.6	47 ± 13

Data are expressed in means ± SD.

Quantification of β-gal staining was made in ten randomly selected 20 × microscopic fields per tissue in each mouse as described in methods.