Publications by authors named "Naheed Mahmood"

HIV-1 uses glycans on gp120 to occlude its highly immunogenic epitopes. To better elucidate escape mechanisms of HIV-1 from carbohydrate-binding agents (CBA) and to understand the impact of CBA-escape on viral immune evasion, we generated and examined the biological properties of HIV-1 resistant to cyanovirin-N (CV-N) or cross-resistant to additional CBAs. Genotypic and phenotypic characterization of resistant env clones indicated that 3-5 high-mannose residues from 289 to 448 in the C2-C4 region of gp120 were mutated and correlated with the resistance levels.

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The first, critical stage of HIV-1 infection is fusion of viral and host cellular membranes initiated by a viral envelope glycoprotein gp120. We evaluated the potential to form a chimeric protein entry inhibitor that combines the action of two gp120-targeting molecules, an allosteric peptide inhibitor 12p1 and a higher affinity carbohydrate-binding protein cyanovirin (CVN). In initial mixing experiments, we demonstrated that the inhibitors do not interfere with each other and instead show functional synergy in inhibiting viral cell infection.

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Cyanovirin-N (CV-N) is a microbicide candidate that inactivates a wide range of HIV strains by binding to gp120. Production of CV-N, or any protein microbicide, needs to be at extremely high levels and low cost to have an impact on global health. Thus, it is unlikely that fermentor-based systems will be suitable, including recombinant E.

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This paper describes an approach to prevent HIV-cell fusion by disrupting the interaction between HIV protein gp120 and CD4 receptor. The CD4 residues Phe43 and Arg59 make important interactions with gp120. Small molecule analogues were made to mimic the crucial features of these residues.

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The crystal structure of a gp120/CD4/Fab17b complex was analysed leading to the design of several peptide libraries in the hope of obtaining novel gp120/cell membrane receptor interaction inhibitors, especially inhibitors of gp120/CD4 and gp120/chemokine receptor interactions. Syntheses of tri- and tetra- and pentapeptides were performed via a solid phase synthesis methodology using a Rink Amide MBHA resin and a Fmoc strategy giving C-terminal amide form peptides. Compounds were assayed against C8166 cells infected by HIV-1 IIIB and screened using a gp120 binding assay and the FIGS reporter gene assay.

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Various acylated proteins have been reported in the literature to possess anti-HIV activity. Described here is the preparation of lysine monomers, dimers and trimers acylated with various anhydrides and dioxalanones as simplified mimics of the acylated proteins. Compounds were assayed against HIV-infected C8166 cells and some showed weak anti-HIV activity.

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