TABLE 3.

Detection of latent MCMV in BALB/c mice immunized with 200 PFU of ΔM83 and challenged with a lethal dose of MCMV K181^a

Gene amplifiedb	No. of positive PCRs/no. of reactions for individual mice infected with the following virusesc:
	Uninf.		ΔM83 only				ΔM83 + K181
	Mouse 1	Mouse 2	Mouse 1	Mouse 2	Mouse 3	Mouse 4	Mouse 1	Mouse 2	Mouse 3	Mouse 4	Mouse 5	Mouse 6
IE1	0/6	0/6	2/6	1/6	0/6	2/6	6/6	6/6	0/13	6/6	4/4	4/4
gpt	0/4	0/4	1/4	1/4	1/4	2/4	0/4	1/4	0/4	0/4	2/4	0/4

^aThe same BALB/c mice described in Table 2 that were i.p. immunized with 200 PFU of tissue culture-derived ΔM83 were either challenged with K181 (see Table 2) or left unchallenged. Five months after the challenge day, mice were sacrificed, spleens were harvested, splenic stromal fractions were prepared, and genomic DNA was isolated for nested PCR. 

^bThe same genomic DNA preparations were used for nested-PCR detection of both MCMV IE1 sequences or gpt sequences from ΔM83. 

^cVirus inoculation groups: Uninf., uninfected; ΔM83 only, ΔM83 immunization only; ΔM83 + K181, ΔM83 immunization and K181 challenge.