Generation of HIV-1/HIV-2 cross-reactive peptide antisera by small sequence changes in HIV-1 reverse transcriptase and integrase immunizing peptides.
We have generated peptide antisera against selected regions in HIV-1 and HIV-2 reverse transcriptase (RT) and integrase (IN) to investigate the specificity of determinants governing the immune response. Peptides representing homologous regions (>50%) in the N- and C-termini and central portions of these proteins were synthesized and injected into rabbits. HIV-1 and HIV-2 IN peptide antisera inhibited IN-mediated cleavage of an HIV-1 DNA oligonucleotide substrate in a 3' processing assay, while anti-RT or normal sera had no effect. None of the RT sera inhibited RT activity. In Western blots, HIV-2 antisera directed against RT or IN peptides recognized HIV-2 RT and IN proteins, respectively, as expected, but also cross-reacted with the corresponding HIV-1 proteins. By contrast, corresponding HIV-1 antisera were type-specific. In some cases, HIV-1 cross-reactive antisera could be generated by immunization with HIV-1 chimeric peptides with as few as two residues in the HIV-1 sequence changed to the corresponding HIV-2 amino acids. The finding that a type-specific response can be converted to a cross-reactive response suggests alternate strategies for developing new diagnostic reagents which detect HIV-1 and HIV-2. In addition, our results provide a general model for generating HIV peptide vaccines with dual specificity against HIV-1 and HIV-2.
Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD, USA.
M
M
Klutch
A M
AM
Woerner
C J
CJ
Marcus-Sekura
J G
JG
Levin
D000595:Amino Acid Sequence; D000818:Animals; D015153:Blotting, Western; D017124:Conserved Sequence; D003429:Cross Reactions; D019427:HIV Integrase / Q000276:immunology*; D054303:HIV Reverse Transcriptase / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007106:Immune Sera / Q000378:metabolism / Q000494:pharmacology; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D012194:RNA-Directed DNA Polymerase / Q000235:genetics / Q000276:immunology*; D011817:Rabbits; D016914:Ribonuclease H / Q000737:chemistry / Q000378:metabolism
D007106:Immune Sera; D010446:Peptide Fragments; D019427:HIV Integrase; C072416:reverse transcriptase, Human immunodeficiency virus 2; D054303:HIV Reverse Transcriptase; D012194:RNA-Directed DNA Polymerase; D016914:Ribonuclease H