Accession Number : ADA300045

Title :   Vaccine Induced Enhancement of Equine Infectious Anemia Virus (EIAV) Replication.

Descriptive Note : Annual rept. 15 Jul 94-14 Jul 95,

Corporate Author : PITTSBURGH UNIV PA SCHOOL OF MEDICINE

Personal Author(s) : Montelaro, Ronald C.

PDF Url : ADA300045

Report Date : 14 AUG 1995

Pagination or Media Count : 26

Abstract : We have used the equine infectious anemia virus (EIAV) system to antibody dependent enhancement (ADE) of lentivirus replication and disease by experimental EIAV vaccines, as an animal model for human AIDS vaccine studies. During the current project period we have performed in parallel experimental immunizations of Shetland ponies with several EIAV glycoprotein subunit vaccines to evaluate the risk of enhancement by the different subunit vaccines. The results of these studies demonstrate a high propensity for immune enhancement in ponies immunized with a baculovirus expressed recombinant gp9O vaccine or with a subunit vaccine containing HPLC-purified viral gp90. Th contrast, a subunit vaccine based containing both of the EIAV envelope proteins (gp9O and gp45) and purified by lectin affinity chromatography produced a high degree of protection against virus challenge. Using immune serum from these immunized ponies, we have also developed in vitro ADE assays and evaluated the correlation of these assays with in vivo enhancement. Although the in vitro ADE assay remains to be optimized, initial results suggest that in vitro ADE assays may in fact distinguish between enhancing and protective immune responses in experimentally vaccinated ponies.

Descriptors :   *VACCINES, *ANEMIAS, OPTIMIZATION, RISK, MODELS, HUMANS, PROTEINS, GLYCOPROTEINS, IN VITRO ANALYSIS, PROTECTION, ANTIBODIES, ANIMALS, IMMUNE SERUMS, PARALLEL ORIENTATION, RESPONSE(BIOLOGY), IMMUNITY, IN VIVO ANALYSIS, ENVELOPE(SPACE), IMMUNIZATION, CHROMATOGRAPHY.

Subject Categories : Medicine and Medical Research

Distribution Statement : APPROVED FOR PUBLIC RELEASE