Fig. 4

Anti-CD134 and anti-SU antibodies significantly inhibit FIV replication in vitro. a Whole serum from CD134 and CD134+SU vaccinated cats produced significant enhancement of FIV replication in GFox cells (CD134 p = 0.0005; CD134+SU p = 0.047), indicated by significantly decreased percent inhibition compared to FIV only infections. Sham vaccinated serum did not significantly inhibit infection. b Antibody fractions representing anti-CD134, anti-SU, and anti-293S were enriched or depleted from serum as described in the text, and analyzed for ability to inhibit in vitro viral infection. Significant inhibitory effects were observed with purified anti-SU IgG and heat-inactivated serum containing anti-SU, anti-CD134, and anti-293S IgG (Table 1). Enriched anti-CD134 (c) and anti-SU (d) antibodies recovered from serum of CD134 and CD134+SU vaccinated cats demonstrated significant inhibition of FIV replication in vitro (SI Table 2), confirming the individual capacity to inhibit FIV infection reported by Grant et al.³¹