TABLE 2.

Response of CD8⁺ T cells to stimulation with serovar Typhi Ty21a^a

Volunteer	T-cell proliferation (cpm)		IFN-γ production (pg/ml)
	Preb	Fold increasec	Pre	Fold-increase
3	80	1.7	<100	3.6
4	270	4.3	<100	15
6	130	1.5	<100	9.2
5	550	35	3,020	13
7	230	37	4,960	0.65
8	640	28	12,100	1.5

^aPeripheral blood CD8⁺ T cells and APC were stimulated with 10⁷ heat-killed serovar Typhi Ty21a bacteria/ml.

^bPre, results from samples taken before vaccination.

^cResults from the peak time points (7 to 21 days after the onset of vaccination) were divided by the prevaccination results.