TABLE 2.

S. sonnei LPS-specific immune responses in 13 volunteers after WRSS1 vaccination and subsequent S. sonnei 53G challenge

Volunteer serial no.	Postimmunization							Postchallengee							Clinical symptom(s) related to challenge
	WRSS1 sheddinga (days)	ASC count/106 PBMCsb			Fold increase inc:			53G sheddinga (days)	ASC count/106 PBMCsb			Fold increase in serum Ab titersc		Fold increase in fecal IgA titers/100 μg of T-IgAc
					Serum Ab titers		Fecal IgA titers/100 μg of T-IgA
		IgA	IgG	IgM	IgA	IgG			IgA	IgG	IgM	IgA	IgG
1	8	138	30	80	75			5	490	160	130	11
2	1					4	9	3	530	600		4		8
3	9	1,290	290	140		4	29	6	6,870	3,980	1,710	64	22	9	Dysentery
4	7	79	23	7			4		144	35	14				Myalgia, headache, malaised
5	1	7	5
6	6		20		6		5								Dysentery
7	0							1	46	14				4
8	0							2	930	1,000	100	36	20
9	0							0
10	0						5	4	4,730	7,480	1,070	169	135		Diarrhea, fever
11	2	12	10
12	6		8		4	8
13	11	420	470		4	7

^aNumber of days of shedding based on culture and/or PCR of fecal sample.

^bOnly ASC counts of ≥5 ASCs per 10⁶ PBMCs are shown.

^cA ≥4-fold increase in antibody titers was considered significant. Ab, antibody.

^dVolunteer serial number 4 had AE but did not meet the criteria of clinical endpoint (diarrhea, dysentery, fever, or shigellosis).

^eVolunteers 11, 12, and 13 were not challenged with strain 53G.