Table 3.

Cytokine production by memory cells specific for GK-1^a

Priming/booster group	Mean ± SD cytokine concn (pg/ml)
	Spleen		Peyer's patches
	IFN-γ	IL-4	IFN-γ	IL-4
Nonvaccinated	302.2 ± 18.7a	165.6 ± 25.6a	83.7 ± 14.9a	31.4 ± 13.9a
GK-1/GK-1	493.4 ± 53.4b	195.9 ± 31.5a	168.9 ± 18.3b	78.9 ± 12.6a
BLS-GK-1/GK-1	690.6 ± 45.9c	289.7 ± 21.5b	156.2 ± 10.9b	100.3 ± 17.7a
BLS + GK-1/GK-1	1,079.0 ± 172.1d	417.5 ± 51.3c	216.3 ± 13.2b	129.1 ± 15.2a,b

^aGroups of 9 mice were orally primed with GK-1, BLS-GK-1, or BLS plus GK-1 and boosted with GK-1. At 15 days after the third immunization, lymphocytes were recovered from PP, MLN, and spleen cells, and the lymphocytes from groups of three mice were pooled and placed in 12-well cluster plates. The plates were incubated at 37°C 5% in a CO₂ humidified atmosphere supplemented with RPMI 1640 in the presence or absence of BLS or GK-1, according to the immunization protocol. Twelve hours before supernatant collection, ConA was added to nonimmunized and GK-1-immunized cells. Supernatants were collected and stored at −80°C until they used to determine the cytokine levels. Data represent the cytokine concentration secreted by tissue cells. Different letters indicate significant differences at P < 0.05 (Tukey-Kramer multiple-comparisons test).