The C-peptides used to prevent HIV infection, such as T20 and C34, are chemically synthesized, making them costly drugs. The sensitivity of peptides to protease also restricts their clinical application. We showed pre...
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The C-peptides used to prevent HIV infection, such as T20 and C34, are chemically synthesized, making them costly drugs. The sensitivity of peptides to protease also restricts their clinical application. We showed previously that C52L, a recombinant peptide produced in bacteria, is a potent anti-HIV C-peptide, although most of the peptide accumulates in inclusion bodies. Here we applied leucine and glutamine scanning mutagenesis to the heptad-repeat of C52L to produce an optimized variant of C52L that is potent and soluble when expressed in bacteria. We present that the substitution of Asn656 and Glu659 with leucine (peptide L14 and L15, respectively) can increase the helical content of this peptide. These substitutions also result in soluble expression. We measured the inhibitory activities of these mutant peptides against laboratory-adapted HIV-1 strains and found that L15 and its parental peptide C52L have equivalent anti-HIV activities. Moreover, L15 was found to be more stable to proteinase K digestion than C52L. Thus, we show that the L15 peptide can be expressed in a soluble state and exhibits potent anti-HIV activity. This peptide may be further developed as an anti-HIV therapeutic and/or microbicide for the prevention of HIV sexual transmission.
Purpose: To evaluate using in-vitro and in-vivo models the feasibility and capture efficiency of a new self-convertible inferior vena cava filter (SCF), equipped with a biodegradable self-converting switch. Materials ...
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Purpose: To evaluate using in-vitro and in-vivo models the feasibility and capture efficiency of a new self-convertible inferior vena cava filter (SCF), equipped with a biodegradable self-converting switch. Materials and Methods: Capture rates were tested in an in-vitro flow model for simulated supine and upright positions with clot diameters of 3 mm and 5 mm and tube diameters of 22 mm, 25 mm, and 28 mm. In the in-vivo study, five filters were implanted in five adult dogs. Venography was performed after the procedure every 2 weeks until filter conversion. Results: All filters were successfully implanted and completely converted with a mean trapping efficiency of 75.5% in the in-vivo study. The SCF was most efficient at 92% in the upright orientation with 5-mm clots and a 22-mm caval diameter. All five filters exhibited successful delivery and conversion in vitro. The SCFs were manually manufactured without barbs or hooks, and because of this feature, migration occurred. Conclusions: The SCF is feasible and highly efficient and converts itself successfully. Evaluation is planned of future prototypes with appropriate modifications for risk of migration of the filter.
HIV-1 gp41 prehairpin fusion intermediate (PFI) composed of three N-terminal heptad repeats (NHR) plays a crucial role in viral fusion and entry and represents an attractive target for anti-HIV therapeutics (e.g., enf...
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HIV-1 gp41 prehairpin fusion intermediate (PFI) composed of three N-terminal heptad repeats (NHR) plays a crucial role in viral fusion and entry and represents an attractive target for anti-HIV therapeutics (e.g., enfuvirtide) and vaccines. In present study, we constructed and expressed two recombinant gp41 PFI mimetics, designated N46Fd and N46FdFc. N46Fd consists of N46 (residues 536-581) in gp41 NHR and foldon (Fd), a trimerization motif. N46FdFc is composed of N46Fd fused with human IgG Fe fragment as an immunoenhancer. We immunized mice with N46 peptide, N46Fd and N46FdFc, respectively, and found that only N46FdFc elicited neutralizing antibody response in mice against infection by HIV-1 strains IIIB (clade B, X4), 92US657 (clade B, R5), and 94UG103 (clade A, X4R5). Anti-N46FdFc antibodies inhibited PIE7 binding to PFI, blocked gp41 six-helix bundle formation, and suppressed HIV-1 mediated cell-cell fusion. These findings provide an important clue for developing recombinant gp41 PFI mimetics-based HIV vaccines. (C) 2010 Elsevier Inc. All rights reserved.
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