Poster Abstracts • OFID 2017:4 (Suppl 1) • S521 Methods. IDLV were produced by co-transfection of transfer, packaging, and envelope plasmids in 293T cells and purification on sucrose gradients. IDLV were normalized using a colorimetric reverse transcriptase assay. Plasmid expressing mAb VN04-2 was provided by B. Hanson. mAb in the supernatant of transduced cells were detected by western blot and quantified by the Easy-Titer Human IgG Assay Kit. For in vivo studies, groups of 6-8 weeks old mice

more »

... eceived IDLV either by intranasal (in) or intramuscular (im) route. mAb production was detected by western blot and ELISA. Mice were challenged using the recombinant IAV VNH5N1-PR8/CDC-RG derived from IAV A/Vietnam/1203/2004. Results. We engineered IDLV producing the humanized mAb VN04-2 (IDLV-VN4-2), which is broadly neutralizing against H5 IAV. We found that after transduction of 293T cell with different dosages IDLV-VN4-2, the production of mAb was time and dose dependent. mAb were also functional, and bind specifically H5 HA but not other IAV proteins. We also measured VN04-2 production in the serum of mice 3, 6, 9, 14, 21 and 30 days after in or im administration of IDLV-VN4-2. We found that levels of mAb were sustained. In separate experiments 5/5 mice receiving IDLV-VN4-2 by the in route and 2/5 mice receiving it by the im route were protected from lethal IAV challenge. Conclusion. Our data suggest that IDLV may represent an attractive candidate for vector-mediated immunization against infectious disease. Disclosures. All authors: No reported disclosures. 1660.