De Groot A, Frost J, Gonzalez M, Saint-Aubin C, Sbai H, Skowron G, Martin W; Conference on Retroviruses and Opportunistic Infections.
Program Abstr 8th Conf Retrovir Oppor Infect Conf Retrovir Oppor Infect 8th 2001 Chic Ill. 2001 Feb 4-8; 8: 99 (abstract no. 195).
Brown Univ.
Background: We believe that broadening CTL responses across HIV-1 proteins and HIV-1 strains or clades will improve HIV vaccine immunogenicity and relevance in the global context of the HIV epidemic. We've applied these principles to developing our "world clade" HIV-1 vaccine. Methods: We performed in vitro studies of novel MHC ligands/CTL epitopes from HIV sequences; these ligands were selected for absolute conservation across HIV-1 strains by Conservatrix, then screened for potential immunogenicity using EpiMatrix (both computer algorithms were developed by the TB/HIV Research Lab at Brown University). Binding of predicted peptides ranging from 8 to 11 amino acids in length to the surface of MHC allele-specific TAP-deficient cell lines was measured by FACS (# binders, % binders). CTL responses (CTLR, % CTL) of PBMC derived from healthy, HIV-1-infected individuals (pts) were measured by restimulating PBMC in vitro and measuring gamma-interferon release by ELISpot in response to peptide-pulsed targets. Binding assays (3 concentrations) were repeated 4 times (counted as positive if 10% greater than background and p < 0.05) ELIspot responses were considered positive if the number of spots was twofold greater than background. Results: 100 peptides have been tested thus far. Binding and CTL results are shown here: [table: see text] 71% of the peptides bound to T2 cells expressing the corresponding HLA molecule (52% of A2 peptides, 84% of A11 peptides, and 76% of B7 peptides), and 10 to 60% of the peptides stimulated a CTL response from an HLA-matched patient in vitro. Twenty-five A3 peptides were also selected; 56% of these stimulated an in vitro ELIspot response (A3 binding assays not done). Conclusion: These studies re-confirm the power of bioinformatics for the selection of highly conserved, immunogenic HIV-1 vaccine epitopes. DNA plasmid constructs containing these epitopes (aligned in a tandem fashion) are being tested in the laboratory.
Publication Types:
Keywords:
- AIDS Vaccines
- Acquired Immunodeficiency Syndrome
- Case-Control Studies
- Computational Biology
- Epitopes
- HIV
- HIV Antigens
- HIV Infections
- HIV Seropositivity
- HIV-1
- Humans
- In Vitro
- Selection (Genetics)
- T-Lymphocytes, Cytotoxic
- genetics
- immunology
- reverse transcriptase, Human immunodeficiency virus 1
Other ID:
UI: 102243976
From Meeting Abstracts