RESUMO
A major goal for HIV-1 vaccine development is an ability to elicit strong and durable broadly neutralizing antibody (bNAb) responses. The trimeric envelope glycoprotein (Env) spikes on HIV-1 are known to contain multiple epitopes that are susceptible to bNAbs isolated from infected individuals. Nonetheless, all trimeric and monomeric Env immunogens designed to date have failed to elicit such antibodies. We report the structure-guided design of HIV-1 cyclically permuted gp120 that forms homogeneous, stable trimers, and displays enhanced binding to multiple bNAbs, including VRC01, VRC03, VRC-PG04, PGT128, and the quaternary epitope-specific bNAbs PGT145 and PGDM1400. Constructs that were cyclically permuted in the V1 loop region and contained an N-terminal trimerization domain to stabilize V1V2-mediated quaternary interactions, showed the highest homogeneity and the best antigenic characteristics. In guinea pigs, a DNA prime-protein boost regimen with these new gp120 trimer immunogens elicited potent neutralizing antibody responses against highly sensitive Tier 1A isolates and weaker neutralizing antibody responses with an average titer of about 115 against a panel of heterologous Tier 2 isolates. A modest fraction of the Tier 2 virus neutralizing activity appeared to target the CD4 binding site on gp120. These results suggest that cyclically permuted HIV-1 gp120 trimers represent a viable platform in which further modifications may be made to eventually achieve protective bNAb responses.
Assuntos
Anticorpos Neutralizantes/sangue , Desenho de Fármacos , Anticorpos Anti-HIV/sangue , Proteína gp120 do Envelope de HIV/imunologia , Proteína gp120 do Envelope de HIV/metabolismo , Infecções por HIV/imunologia , HIV-1/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Sítios de Ligação , Cristalografia por Raios X , Epitopos/imunologia , Cobaias , Anticorpos Anti-HIV/imunologia , Infecções por HIV/sangue , Infecções por HIV/virologia , Humanos , Ligação Proteica , Conformação Proteica , Multimerização ProteicaRESUMO
Optimization studies using an HIV RNase H active site inhibitor containing a 1-hydroxy-1,8-naphthyridin-2(1H)-one core identified 4-position substituents that provided several potent and selective inhibitors. The best compound was potent and selective in biochemical assays (IC(50)=0.045 µM, HIV RT RNase H; 13 µM, HIV RT-polymerase; 24 µM, HIV integrase) and showed antiviral efficacy in a single-cycle viral replication assay in P4-2 cells (IC(50)=0.19 µM) with a modest window with respect to cytotoxicity (CC(50)=3.3 µM).
Assuntos
Fármacos Anti-HIV/farmacologia , Inibidores Enzimáticos/farmacologia , HIV-1/enzimologia , Ribonuclease H/antagonistas & inibidores , Fármacos Anti-HIV/química , Inibidores Enzimáticos/química , Células HeLa , Humanos , Naftiridinas/química , Naftiridinas/farmacologiaRESUMO
This Letter describes the design, synthesis, and biological evaluation of novel 3-indole sulfonamides as potent non-nucleoside reverse transcriptase inhibitors (NNRTIs) with balanced profiles against common HIV RT mutants K103N and Y181C.
Assuntos
Indóis/química , Inibidores da Transcriptase Reversa/farmacologia , Sulfonamidas/farmacologia , Cristalografia por Raios X , Transcriptase Reversa do HIV/antagonistas & inibidores , Transcriptase Reversa do HIV/genética , Modelos Moleculares , Mutação , Inibidores da Transcriptase Reversa/química , Sulfonamidas/químicaRESUMO
A series of 10-hydroxy-7,8-dihydropyrazino[1',2':1,5]pyrrolo[2,3-d]pyridazine-1,9(2H,6H)-diones was synthesized and tested for their inhibition of HIV-1 replication in cell culture. Structure-activity studies indicated that high antiviral potency against wild-type virus as well as viruses containing integrase mutations that confer resistance to three different structural classes of integrase inhibitors could be achieved by incorporation of small aliphatic groups at certain positions on the core template. An optimal compound from this study, 16, inhibits integrase strand-transfer activity with an IC(50) value of 10 nM, inhibits HIV-1 replication in cell culture with an IC(95) value of 35 nM in the presence of 50% normal human serum, and displays modest pharmacokinetic properties in rats (i.v. t(1/2)=5.3 h, F=17%).