elastin and HIV-Infections

Most peptide drugs have short half-lives, necessitating frequent injections that may induce skin sensitivity reactions; therefore, versatile prolonged-release delivery platforms are urgently needed. Here, we focused on an oxidatively and thermally responsive recombinant elastin-like polypeptide with periodic cysteine residues (cELP), which can rapidly and reversibly form a disulfide cross-linked network in which peptide can be physically incorporated. As a model for proof of concept, we used enfuvirtide, an antiretroviral fusion-inhibitor peptide approved for treatment of human immunodeficiency virus (HIV) infection. cELP was mixed with enfuvirtide and a small amount of hydrogen peroxide (to promote cross-linking), and the soluble mixture was injected subcutaneously. The oxidative cross-linking generates a network structure, causing the mixture to form a hydrogel in situ that serves as an enfuvirtide depot. We fabricated a series of enfuvirtide-containing hydrogels and examined their stability, enfuvirtide-releasing profile and anti-HIV potency in vitro. Among them, hydrophobic cELP hydrogel provided effective concentrations of enfuvirtide in blood of rats for up to 8 h, and the initial concentration peak was suppressed compared with that after injection of enfuvirtide alone. cELP hydrogels should be readily adaptable as platforms to provide effective depot systems for delivery of other anti-HIV peptides besides enfuvirtide.. In this paper, we present an anti-HIV peptide delivery system using oxidatively and thermally responsive polypeptides that contain multiple periodic cysteine residues as an injectable biomaterial capable of in situ self-gelation, and we demonstrate its utility as an injectable depot capable of sustained release of anti-HIV peptides. The novelty of this work stems from the platform employed to provide the depot encapsulating the peptide drugs (without chemical conjugation), which consists of rationally designed, genetically engineered polypeptides that enable the release rate of the peptide drugs to be precisely controlled.

Topics: Animals; Cell Line; Cross-Linking Reagents; Drug Implants; Elastin; Enfuvirtide; HIV Envelope Protein gp41; HIV Infections; HIV-1; Humans; Hydrogels; Hydrogen Peroxide; Male; Peptide Fragments; Rats; Rats, Sprague-Dawley; Recombinant Proteins

Combined antiretroviral therapy (cART) attenuates hepatic fibrosis in hepatitis C virus and HIV coinfected patients. However, the role of HIV or cART on hepatic fibrosis in HIV monoinfection is discussed controversially. During liver fibrosis, matrix metalloproteinases (MMPs) degrade extracellular matrix (ECM) proteins into small soluble fragments, which reflect hepatic remodeling processes. This study used these novel biomarkers to investigate the effect of HIV and cART on hepatic fibrosis remodeling.. In 249 patients with HIV monoinfection and 55 healthy controls, the serum levels of MMP-degraded collagen type III (C3M), biglycan (BGM), elastin (ELM), as well as the formation marker 7S (P4NP 7S), and MMP-degraded collagen type IV (C4M) were determined using specific ELISAs. Sixty-eight patients underwent a follow-up visit 3 years later including assessment of ECM markers and fibrosis using transient elastography (Fibroscan).. C3M, BGM, C4M and P4NP 7S were significantly elevated in HIV patients compared to controls and correlated to HIV viral loads and inversely to cART duration. C4M, P4NP 7S and ELM were lower in patients under cART therapy and in patients without HIV viremia, indicating that lowering of the HIV load by cART attenuates remodeling of ECM. The levels of C3M, C4M, P4NP 7S and ELM correlated significantly with the progression of fibrosis in these patients.. Specific therapy of patients with HIV monoinfection also beneficially influences liver fibrosis. These novel markers of liver fibrosis remodeling may help to monitor the hepatic effects by HIV therapy.

Topics: Adult; Antiviral Agents; Biglycan; Biomarkers; Coinfection; Collagen Type III; Cross-Sectional Studies; Disease Progression; Drug Therapy, Combination; Elasticity Imaging Techniques; Elastin; Extracellular Matrix; Female; Follow-Up Studies; Hepatitis C; HIV Infections; Humans; Liver Cirrhosis; Longitudinal Studies; Male; Middle Aged; Peptide Mapping