MUCOSAL IMMUNE-RESPONSE TO AN HIV C4 V3 PEPTIDE FOLLOWING NASAL OR INTESTINAL IMMUNIZATION OF RABBITS/

The HIV env-encoded synthetic peptide T1-SP10MN(A) contains immunodomi nant epitopes of the C4/V3 regions of gp120, The mucosal immunogenicit y of this peptide in various vaccine preparations was first tested in rabbits using chronically isolated Thiry-Vella (T-V) heal loops. Intes tinal and serum samples collected from rabbits immunized via T-V loops demonstrated secretory IgA (S-IgA) and IgG anti-T1-SP10MN(A), respect ively, when assayed by ELISA. Intranasal delivery of the peptide suppl emented with cholera toxin (CT) resulted in serum IgG and S-IgA anti-T 1-SP10MN(A) in vaginal and nasal secretions. This study further demons trates the utility of rabbits as a convenient animal model for HIV vac cine research and the relationship between nasal immunization and vagi nal immunity.