TABLE 2.

IFN-γ production in vitro by spleen cells from vaccinated μMT and B6 mice^a

Mouse group	n	No. of lymphocytes (106)/spleenb	No. of cells (106)c of type:		IFN-γ production
			CD45RBloCD4+	CD45RBloCD8+	U/ml	U/spleend
Vaccinated μMT	4	6.06 ± 0.78	1.28e ± 0.12 (37.6f ± 1.37)	0.36e ± 0.05 (21.2f ± 7.68)	239.0 ± 69.6	1,330e ± 453
Naive μMT	4	7.88 ± 1.72	1.07 ± 0.18 (31.1 ± 7.57)	0.18 ± 0.04 (7.78 ± 3.10)	99.3 ± 71.4	700 ± 403
Vaccinated B6	4	112.5 ± 23.1	9.47 ± 3.67 (46.6 ± 7.75)	2.53 ± 1.16 (29.5 ± 9.4)	99.5 ± 61.5	4,860 ± 2,121
Naive B6	4	86.9 ± 25.0	6.01 ± 1.53 (47.0 ± 5.92)	0.73 ± 0.23 (11.1 ± 0.52)	58.0 ± 62.4	2,046 ± 1,931

^aMice were vaccinated by two injections of ts-4 tachyzoites, and spleens were harvested 21 days after the second injection. 

^bCalculated by multiplying the number of cells per spleen by the percentage of cells within a forward scatter-side scatter gate defining lymphocytes. Values are means ± standard deviations. 

^cCalculated by multiplying the number of lymphocytes per spleen by the percentage of CD45RB^loCD4⁺ or -CD8⁺ cells within the lymphocyte gate. Numbers in parentheses are the percentages of CD45RB^lo cells within the total CD4⁺ and CD8⁺ populations. 

^dEstimated by multiplying the units produced per 6 × 10⁵ spleen cells in vitro by the number of cells per spleen. 

^eSignificantly (P < 0.05) less than the corresponding population of cells from vaccinated B6 mice. 

^fSignificantly (P < 0.05) greater than the percentage for the corresponding population of naive μMT mouse cells but not significantly different from the percentage for cells from vaccinated B6 mice.