TABLE 1.

IFN-γ levels in sera and homogenates of lung tissues from infected mice

Source	IFN-γ level (pg) for indicated treatment groupa
	Saline	J774-Vector	J774-IL-12
Serum	<15b	<15	1,580
Lung homogenates	<15	200	1,300

^aIFN-γ levels per milliliter of serum and per 100 mg of lung tissue obtained from groups of 10 mice at 12 days postinfection. 

^bLower limit of sensitivity of the assay.