TABLE 6.

Assessment of neutralizing antibody cross-reactivity against heterologous virus variants

Peptide immunogen	Animal no.a	Titer of neutralizing antibodies to indicated strain ofb:
		SHIV			HIV-1
		KB9	HXBc2	KU2	MN	SF2
C4/89.6-V3	321-94	<1:20	<1:20	<1:20	1:62	<1:20
	358-95	<1:20	<1:20	<1:20	1:471	<1:20
	539-92	<1:20	1:33	<1:20	1:294	<1:20
	556-92	<1:20	<1:20	<1:20	1:188	<1:20
C4/89.6P-V3	13947	1:28	<1:20	<1:20	1:1,089	<1:20
	15032	1:21	<1:20	<1:20	1:97	<1:20
	17071	<1:20	<1:20	<1:20	1:253	<1:20
	13789	1:61	1:25	<1:20	1:44	<1:20
	15075	<1:20	<1:20	<1:20	1:106	<1:20
	15475	1:25	<1:20	<1:20	1:892	<1:20
	18351	<1:20	<1:20	<1:20	1:89	<1:20

^aSerum samples were obtained on the day of challenge (2 weeks after the final peptide inoculation). 

^bSHIV-89.6, SHIV-KB9 and SHIV-KU2 were grown in human PBMC. SHIV-HXBc2, HIV-1 MN, and HIV-1 SF2 were grown in H9 cells. All assays were performed in MT-2 cells with the exception of that for HIV-1 SF2, which was assayed in CEMx174 cells. Titers are the serum dilutions at which 50% of cells were protected from virus-induced killing.