TABLE 1.

Immunogens used and their FIV contents^a

Immunogen	Composition	Mean % IF-positive cells ± SDb	Mean virus content/106 cells ± SD		Infectivity
			Proteinc (μg)	RNAd (no. of copies)	In vitroe	In vivof
FCPLB	Infected, fixed PLB	54 ± 1	50 ± 2	(5.0 ± 0.6) × 109	−	−
ID-1	PLB + AT2-FIV	23 ± 2	15 ± 1	(5.8 ± 0.8) × 108	−	−
ID-2	PLB + AT2-FIV + peptide SU5	20 ± 3	11 ± 1	(2.6 ± 0.5) × 108	−	−
ID-3	PLB + AT2-FIV + peptide TM59	24 ± 1	12 ± 2	(2.4 ± 0.3) × 108	−	−
Mock-1	PLB	0	0	<103	−	−
Mock-2	PLB + peptides SU5 and TM59	0	0	<103	−	−

^aValues shown are the means ± the standard deviations of the immunogens prepared for each prospective vaccinee.

^bThat is, the percent membrane IF-positive cells when probed with anti-FIV serum and anti-cat IgG polyclonal serum conjugated with fluorescein isothiocyanate.

^cCells were lysed in sodium dodecyl sulfate-electrophoresis sample buffer at 60°C for 30 min, electrophoresed, and examined by using a semiquantitative Western blot assay.

^dCells were lysed and tested for viral RNA by TM-PCR.

^eCells were tested for FIV infectivity by inoculation into MBM cells, which were then monitored for FIV production for 8 weeks.

^fBased on testing immunized cats by virus isolation and TM-PCR 5.5 months after the first inoculation of the immunogens.