TABLE 4.

Neutralization of SHIV-89.6 in MT-2 cells and human PBMC by sera from animals immunized with the C4/89.6-V3 peptide

Animal no.	Inoculationa	Titerb in MT-2 cells	% Reduction in p27 in human PBMCc
321-94	5th	1:55	52
	6th	1:256	77
	7th	1:97	84
	8th	1:74	54
358-95	5th	1:99	48
	6th	1:134	67
	7th	1:85	68
	8th	1:124	53
539-92	5th	1:20	57
	6th	1:80	94
	7th	1:58	91
	8th	1:62	81
556-92	5th	1:50	76
	6th	1:150	93
	7th	1:106	96
	8th	1:177	92

^aAnimals were inoculated with the C4/89.6-V3 peptide immunogen. Serum was obtained 2 weeks after the indicated inoculation. 

^bTiters are the serum dilutions at which 50% of cells were protected from virus-induced killing. 

^cSerum samples were tested at a 1:5 dilution in triplicate. The percent reduction in p27 synthesis is calculated relative to the amount of p27 produced in the presence of the corresponding prebleed sample for animals 321-94 (1,969 pg/ml), 358-95 (1,292 pg/ml), 539-92 (1,967 pg/ml) and 556-92 (1,383 pg/ml).