Structure-activity relationships and mode of action of 5-mercapto-substituted oligo- and polynucleotides as antitemplates inhibiting replication of human immunodeficiency virus type 1

Abstract

Introduction of a reactive 5-mercapto group into some of the cytosine and/or uracil bases of various oligoand polynucleotides by partial thiolation resulted in several potent inhibitors of the replication of human immunodeficiency virus type 1 (HIV-1) in primary human lymphocytes. These compounds exhibited little if any toxicity against uninfected peripheral blood mononuclear cells and showed 15 to 75 times higher antitemplate activity against a p66/p5i HIV-1 recombinant reverse transcriptase (RT) than against the DNA polymerase a from human lymphocytes. In contrast, the unthiolated oligo-and polynucleotides are void of antitemplate activity, and their apparent inhibitory effect on HIV-1 closely paralleled their toxicity for the cells. Partially thiolated poly(dC) (MPdC) was the most potent of all the compounds tested against HIV-1 in peripheral blood mononuclear cells (50% effective concentration, 1.8 ,ug/ml or 0.019 ,uM), while showing low cytotoxicity (>100 ,ug/ml). The corresponding unmodified poly(dC) showed no anti-HIV-1 activity at 50 ,ug/ml but had pronounced cytotoxicity. MPdC was also a potent inhibitor of HIV-1 RT (50% inhibitory concentration, 0.30 ,ug/ml). The inhibitory activities of thiolated homooligo(dCs) against both HIV-1 replication and HIV-1 RT increased with increasing chain length. The heterooligonucleotides included in this study were designed as structural analogs of portions of the natural primer of HIV-1 RT, i.e., tRNArYs. An 18-mer analog of the 3' terminus, complementary (antisense) to the primer-binding site of the HIV-1 genome, was attached to an oligo(dC) tail and 5-thiolated; this increased its activity and decreased its toxicity. This compound will serve as a new lead in the development of more effective antitemplates against HIV-1.

Synthesis and virucidal activity of a water-soluble, configurationally stable, derivatized C60 fullerene

“…This value was of the same order of magnitude as that noted for the antiviral assays ( Table 1). The compound did not demonstrate selectivity against cellular DNA polymerase a (3). The finding that compound 1 inhibits DNA polymerase a in a cell-free system with an IC50 of 4.9 ,uM and also exhibits no cytotoxicity in various cells is consistent with the proposed virucidal mechanism, since one would anticipate some cytotoxicity if the compound were transported intracellularly.…”

(s4dU)35: a novel, highly potent oligonucleotide inhibitor of the human immunodeficiency virus type 1 reverse transcriptase

“…['hey are potent inhibitors of the replication of HIV in prinary human lymphocytes [10]. The poly(U60,hsSU40) proved o be a potent competitive inhibitor of RT [11].…”

“…Their acivities are not strictly dependent on specific nucleic acid seluences. In addition to the nucleoside and non-nucleoside 'ype inhibitors the modified oligonucleotides are another class ,~f RT inhibitors.The most thoroughly studied inhibitory template analogs tre 5-mercaptopyrimidine-containing polynucleotides [7][8][9].['hey are potent inhibitors of the replication of HIV in prinary human lymphocytes [10]. The poly(U60,hsSU40) proved o be a potent competitive inhibitor of RT [11].…”

Derivatives of 4‐amino‐3,6‐disulfonato‐1, 8‐naphthalimide inhibit reverse transcriptase and suppress human and feline immunodeficiency virus expression in cultured cells

“…The standard reaction mixture (l00 j..ll) contained 100 mM Tris-HCI (pH 8.0), 50 mM KCI, 2 mM MgCI 2, 5 mM dithiothreitol, 0.05 U /ml of (rA)n. (dT)12-IR, 1 j..lM [3H] dTTP (Du Pont, NEN Products, Boston, MA; specific activity 50 Ci/rnmol) and 10 j..ll of HIV-1 RT (0.84 U /well). The reaction mixtures were incubated and processed as previously described [Bardos et al, 1992;Eriksson et al, 1989]. Escherichia coli DNA polymerase 1 was obtained from Boehringer Manheim Corp. (Indianapolis, IN).…”