TABLE 1.

Presence of IFN-γ in the supernatant of spleen cell cultures of μMT and WT mice after primary and secondary infection

Infection (days p.i.)a	IFN-γ concn (ng/ml) in cultures stimulated with indicated antigen
	WT		μMT
	ConA	Chl-Ag	ConA	Chl-Ag
Primary (10)	18.5 ± 10.6	32.6 ± 5.6b	12.8 ± 6.2	18.2 ± 4.4b
Reinfection (5)	65.8 ± 12.6	48.6 ± 7.4	54.6 ± 8.8	52.4 ± 6.8

^aAt the indicated time points, groups of five mice were sacrificed and spleen cell cultures were stimulated with the C. abortus antigens (Chl-Ag; 50 μg/ml) or concanavalin A (ConA; 5 μg/ml). When only medium was added to the spleen cells, no production of IFN-γ was observed. Results are expressed as means ± SD and are from one representative experiment of two independent experiments.

^bSignificant differences (P < 0.01) between μMT and WT mice at the same day p.i.