Specific synthetic peptides for detection of and discrimination between HIV-1 and HIV-2 infection.

A panel of highly purified synthetic oligopeptides representing defined parts of the gag and env proteins of HIV-1 and HIV-2 were used as antigens in ELISA for serodiagnosis of HIV-1 and HIV-2 infection. The analysis included sera from 321 HIV-infected patients and 201 healthy controls from the Ivory Coast, where the prevalence is high for both HIV-1 and HIV-2, and sera from European HIV-1-infected individuals. All sera from HIV-1-infected individuals reacted with a 20 amino acid (a.a.) peptide JB-4c (a.a. 594-613) derived from a highly immunogenic conserved region of the external part of gp41. An equally good response was seen in the HIV-2-infected individuals to a 20 a.a. peptide, JB-16c, from the corresponding part of HIV-2 gp36. Both HIV-1- and HIV-2-seropositive individuals responded well to a peptide, JB-8pc (a.a. 427-448), representing the C-terminal end of the putative CD4-binding site of gp120 of HIV-1. The frequency of reactivity to three selected HIV-1 gag peptides derived from p17 and p15 was 60-70% in both HIV-1 and HIV-2-positive sera. To distinguish between HIV-1 and HIV-2 infection, the sera were titrated against the peptides. Although there was a high degree of cross-reactivity at lower serum dilutions, it was possible to discriminate the infections at higher dilutions to the HIV-1 and HIV-2 gp41/gp36 peptides JB-4c and JB-16c. Analysis of serum reactivity to several selected peptides thus allowed the identification of HIV infection, and the discrimination between HIV-1 and HIV-2.(ABSTRACT TRUNCATED AT 250 WORDS)

Acyclic guanosine analogs as inhibitors of human cytomegalovirus.

The acyclic guanosine analogs R- and S-enantiomers of 9-(3,4-dihydroxybutyl)guanine [(R)- and (S)-DHBG], 9-(4-hydroxybutyl)guanine (HBG), and 9-(2-hydroxyethoxymethyl)guanine (ACV) were examined for their effects on human cytomegalovirus (CMV) replication and on CMV DNA synthesis in cell culture as well as for their ability as triphosphates to interact with CMV DNA polymerase. Production of early CMV antigens was not affected. All analogs inhibited CMV DNA synthesis and late viral antigen synthesis. Primary CMV isolates were less susceptible to all tested analogs than was the laboratory strain CMV Ad.169. The triphosphate of ACV was the most potent inhibitor of CMV DNA polymerase, with an observed Ki of 0.0076 microM. The corresponding Ki values of the triphosphates of (R)-DHBG, (S)-DHBG, and HBG were 3.5, 13.0 and 0.23 microM, respectively. All triphosphates of the analogs given above inhibited CMV DNA polymerase in a competitive manner with respect to dGTP. The triphosphates of the analogs also inhibited reactions when the synthetic template poly(dC)oligo(dG)12-18 was used, whereas no inhibition was observed with poly(dA)oligo(dT)12-18. None of the triphosphate analogs supported DNA synthesis in the absence of dGTP, showing that no analog was an alternative substrate to dGTP.

Nucleic acid hybridization, a method to determine effects of antiviral compounds on herpes simplex virus type 1 DNA synthesis.

An application of the nucleic acid hybridization technique to screen effects of antiherpes compounds on herpes simplex virus type 1 (HSV-1) DNA synthesis is described. Whole cells are applied to nitrocellulose filters, their DNA is denatured and fixed to the filter. The resulting DNA spots are hybridized to cloned nick-translated HSV-1 DNA and the amount of hybridization is monitored by autoradiography or scintillation counting. Six antiherpes compounds: bromovinyldeoxyuridine, acyclovir, (R)- and (S)-enantiomers of 9-(3,4-dihydroxybutyl)guanine, 9-(4-hydroxybutyl)guanine and forscarnet, were evaluated for their effects on HSV-1 DNA synthesis. The most active compounds were bromovinyldeoxyuridine and acyclovir, with mean 50% inhibition values (IC50) for four different HSV-1 strains of 0.3 microM and 0.8 microM, respectively. The (R)-enantiomer of the new antiherpes compound 9-(3,4-dihydroxybutyl)guanine was found to be more active than the (S)-enantiomer, with mean IC50s of 6.5 and 14 microM, respectively, while mean IC50s of 2.5 and 68 microM were obtained for 9-(4-hydroxybutyl)guanine and foscarnet, respectively.