Table 3.

Serum bactericidal titers in the presence of baby rabbit complement on a panel of 14 serogroup B strains cultured with or without TPEN

Strain	fHbp family	fHbp expressionc	ZnuD expressionc	Geometric mean titer (EU/ml)b
				Mouse						Guinea pig
				fHbp B or Aa		Control OMVs		ZnuD OMVs		Control OMVs		ZnuD OMVs
				MH agar	MH-TPEN agar	MH agar	MH-TPEN agar	MH agar	MH-TPEN agar	MH agar	MH-TPEN agar	MH agar	MH-TPEN agar
H44/76	B	++	+	3,383	3,539	103	265	3,605	7,903	55	115	331	1,751
NZ98/254	B	+	+	110	388	50	112	69	1,854	50	50	50	2,592
M01-240101	B	+	+	494	509	50	50	519	1,733	50	50	50	2,153
M01-240355	A	+	+	50	50	50	50	50	3,310	50	50	50	2,497
M01-240013	A	+	+	50	50	50	50	50	852	50	50	50	3,706
M01-240149	B	+	+	2,293	2,104	71	50	3,116	3,374	50	50	94	2,961
MC58	B	++	+	3,993	5,786	88	304	1,734	17,486	67	50	240	1,846
18025	B	+/−	+	3,804	4,373	50	182	50	4,872	67	50	234	752
DE 10690-06	B	+/−	+	50	50	50	50	50	937	50	50	50	1,781
M05-0240471	B	+/−	+	50	50	50	50	50	197	50	50	50	2,005
17540	B	−	+	50	50	50	50	50	2,130	50	50	50	8,877
M05-0240072	B	−	+	50	50	50	50	50	3,400	50	50	94	6,315
760676	A	−	+	50	50	50	50	50	1,308	50	50	122	5,311
M98-250771	A	+/−	+	50	50	50	50	50	143	50	50	50	2,021

^aSera from mice immunized with fHbp A or fHbp B were used for SBA with strains expressing fHbp A or fHbp B, respectively.

^bGeometric mean titers (expressed in EU/ml) for 50% killing from three pools of sera per group. Geometric mean titers above the threshold for a positive result (titer of ≥128) are shown in boldface type.

^c++, high; +, medium; +/−, low; −, no expression.