TABLE 2.

Anti-FHA antibody responses in the sera of mice infected with B. pertussis and boosted 14 weeks later with FHA^a

Day and FHA boost	Anti-FHA IgA titer			Anti-FHA IgG titer (103)
	Noninfected	BPSM infected	BPRA infected	Noninfected	BPSM infected	BPRA infected
Day 7
None	<10	108 ± 83	267 ± 49	<0.05	6.49 ± 3.77	6.9 ± 0.7
Intranasal	60	1,313 ± 57	413 ± 37	0.07	69.64 ± 22.35	196.14 ± 9.39
Vaginal	15	131 ± 57	148 ± 20	0.11	17.34 ± 5.64	20.15 ± 6.4
Day 14
None	ND	68 ± 8	102 ± 17	ND	2.14 ± 0.88	5.94 ± 0.84
Intranasal	ND	592 ± 238	368 ± 44	ND	46.04 ± 10.76	41.95 ± 11.38
Vaginal	ND	295 ± 156	111 ± 6	ND	36.76 ± 14.47	42.85 ± 16.3
Day 28
None	<10	39 ± 13	95 ± 7	0.08	2.88 ± 2.18	8.65 ± 1.15
Intranasal	13	667 ± 209	471 ± 52	1.21	76.35 ± 20.47	65.55 ± 10.36
Vaginal	<10	90 ± 28	95 ± 4	0.52	16.69 ± 4.99	26.8 ± 4.8

^aBALB/c mice were infected with BPSM or BPRA and either boosted or not boosted 14 weeks later with 6 μg of FHA by the intranasal or the vaginal route. For noninfected animals, the sera of five mice per time point was pooled before the anti-FHA antibody determination. For infected mice, the results are expressed as the means ± the SEM of four to five mice per group. ND, not determined. Significant differences (P ≤ 0.05) with control mice, as determined by Student's t test, are indicated in boldface.