New generation of Anti-HIV-1 Compounds
New approaches to designing anti-HIV compounds targeting late steps of HIV-1 replication
Tech Area / Field
- MED-DRG/Drug Discovery/Medicine
- BIO-CGM/Cytology, Genetics and Molecular Biology/Biotechnology
8 Project completed
Senior Project Manager
Melnikov V G
Ivanovsky Institute of Virology, Russia, Moscow
- Health Research & Development Foundation, Russia, Moscow\nInstitute of Immunological Engineering, Russia, Moscow reg., Lyubuchany
- University of Massachusetts / Medical School, USA, MA, Worcester
Project summaryThe goal of the project is to design the new generation of membranotropic compounds, which are expected to block HIV-1 entry, assembly and maturation.
Newly developed membranotropic compounds consisting of three components- membranotropic adamantane and norbornene derivatives chemically linked through flexible spacer to a water soluble polyanionic matrix have been shown to be non toxic potent inhibitors of the HIV entry into target cells in vitro (Bukrinskaya et al 1999, US patent 005880154 A, Burstein et al 1999 a, b). The compounds blocked also the self-assembly of Gag precursor p55 and the formation of virus-like particles suggesting that they inhibit early and late steps of viral replication. We propose to investigate the antiviral effect of existing membranotropic compounds on the steps of viral assembly and budding and to prepare the new membranotropic substances with targeted antiviral activity by modification of adamantane and norbornene pharmacophores.
To increase the tropism to the lipid rafts - the cholesterol-rich part of plasma membrane where the assembly takes place - the pharmacophores will be associated with raft tropic substances – cholesterol-like fragments.
The other possibility to increase antiviral properties is to associate pharmacophores with short amino acid sequences, competing with native Gag proteins. Such approach requires the synthesis of peptides that imitate the key domains of Gag proteins responsible for virus assembly, budding and maturation and therefore the precise data about the role of inpidual Gag proteins in the viral assembly.
Our preliminary results show that Gag precursor p55 is cleaved into mature Gag proteins not only in the extracellular virions as generally accepted but much earlier, in infected cells, and intracellularly cleaved MA (cMA) is found in the nucleus and in the membrane fraction. cMA is incorporated into budding virions and is localized in the conical cores of mature virions and possibly is included in the preintegration complex. The preliminary data show that cMA is associated with genomic viral RNA. Besides, we suppose that cMA is involved in virus maturation – formation of conical cores and appearance of infectious activity.
These studies will be continued. The fate of cMA inside the infected cells, its role in virus assembly and infectivity and interaction with the other proteins and genomic viral RNA will be studied. Protease inhibitor Indinavir sulfate will be used to differentiate the cleavage of Gag precursor in budding virions and that in infected cells in pulse-chase experiment. Given that cMA is one of the main targets for antiviral compounds, we propose to associate pharmacophores with peptides imitating MA functional domains. Such compounds will compete with MA in the process of virus assembly and maturation and selectively disturb the steps of viral replication or shift the process to the formation of defective non-infectious virions.
A series of compounds, which potentially fit into the structural pocket of MA near thyrosine 29 of nuclear localization signal, were synthesized using computer assisted modeling. One of the compounds efficiently inactivates interaction between MA and kariopherin –α and inhibits HIV-1 nuclear import (Bukrinsky et al., US patent S1849 793, 1998). It is reasonable to expect that this compound will prevent HIV assembly and maturation.
The new modified polymeric compounds and compounds associated with MA-like synthetic peptides will be studied to identify the most active potent inhibitors that selectively disturb the steps of viral replication regulated by MA. These studies will be performed using laboratory strains and clinical isolates of HIV-1.
As a result of the research on the Project, the new generation of anti-HIV compounds will be developed that will be the promising candidates for AIDS chemotherapy and prevention of HIV transmission.