PurposeThe prevalence of HCV infection has increased during recent years and the incidence reach 3% of the world's population, and in some countries like Egypt, may around 20%. The developments of effective and preventive agents are critical to control the current public health burden imposed by HCV infection. Lactoferrin in general and camel lactoferrin specifically has been shown to have a compatitive anti-viral activity against hepatitis C virus (HCV). The purpose of this study was to examine and compare the anti-infectivity of native human, camel, bovine and sheep lactoferrin on continuous of HCV infection in HepG2 cells.Material and methodsUsed Lfs were purified by Mono S 5/50 GL column and Superdex 200 5/150 column. The purified Lfs were evaluated in two ways; 1. the pre-infected cells were treated with the Lfs to inhibit intracellular replication at different concentrations and time intervals, 2. Lfs were directly incubated with the virus molecules then used to cells infection. The antiviral activity of the Lfs were determined using three techniques; 1. RT-nested PCR, 2. Real-time PCR and 3. Flowcytometric.ResultsHuman, camel, bovine and sheep lactoferrin could prevent the HCV entry into HepG2 cells by direct interaction with the virus instead of causing significant changes in the target cells. They were also able to inhibit virus amplification in HCV infected HepG2 cells. The highest anti-infectivity was demonstrated by the camel lactoferrin.ConclusioncLf has inhibitory effect on HCV (genotype 4a) higher than human, bovine and sheep lactoferrin.

BackgroundLactoferrin (LF) is a member of the transferrin protein family, which is not only a highly abundant breast-milk glycoprotein [1,2], but, being produced by various mucosal epithelial cells, is commonly found in various secretory fluids, such as saliva, tears, and nasal secretions of different mammalian species, including humans, cows, goats, horses, dogs, and several rodents. Furthermore, LF has been identified in the eggs of rainbow trout indicating that this protein is also produced by fish [3]. LF is an essential player of the natural immunity. It is abundant in the upper and lower respiratory tissues, as well as in the digestive and urogenital mucosal tissues, which are often exposed to the colonizing or invasive microbial pathogens. It is broadly distributed in biological fluids, such as milk, saliva, and seminal fluid, and in specific neutrophil granules of polymorphonuclear leukocytes [4]. LF displays a broad range of preventive, therapeutic, and biological activities, including antibacterial, antifungal, antiviral, antioxidant, immunomodulatory, cell-growth modulatory, and binding functions, and neutralizes some bioactive substances, such as lipopolysaccharide (LPS)

In this study, we used a wide spectrum of bioinformatics techniques to evaluate the extent of intrinsic disorder in the complete proteomes of genotypes of four human dengue virus (DENV), to analyze the peculiarities of disorder distribution within individual DENV proteins, and to establish potential roles for the structural disorder with respect to their functions. We show that several proteins (ER, E, 1, 2A and 4A) are predicted to be mostly ordered, whereas four proteins (C, 2k, NS3 and NS5) are expected to have high disorder levels. The profiles of disorder propensities are similar across the four genotypes, except for the NS5 protein. Cleavage sites are depleted in polymorphic sites, and have a high propensity for disorder, especially relative to neighboring residues. Disordered regions are highly polymorphic in type 1 DENV but have a relatively low number of polymorphic sites in the type 4 virus. There is a high density of polymorphisms in proteins 2A and 4A, which are depleted in disorder. Thus, a high density of polymorphism is not unique to disordered regions. Analysis of disorder/ function association showed that the predominant function of the disordered regions in the DENV proteins is protein-protein interaction and binding of nucleic acids, metals and other small molecules. These regions are also associated with phosphorylation, which may regulate their function.Abbreviations CLV, cleavage site; DENV, dengue virus; ELM, eukaryotic linear motif; IDP, intrinsically disordered protein; IDPR, intrinsically disordered protein region; MoRF, molecular recognition feature; NS, non-structural protein. IntroductionDengue fever virus (DENV) is a member of the family Flaviviridae in the genus Flavivirus, that, among other members, includes hepatitis C virus, West Nile virus and yellow fever virus [1]. The Flavivirus genus consists of nearly 80 viruses, many of which are arthropodborne human pathogens that cause a variety of diseases, including dengue fever, plus the associated dengue hemorrhagic fever and dengue shock syndrome, Japanese encephalitis and yellow fever [2]. There are four antigenically related serotypes of the dengue virus (DENV-1, DENV-2, DENV-3 and DENV-4). All four serotypes are known to cause the full spectrum of disease [3]. Infection with one of these serotypes provides immunity for life, but to only that serotype [4]. Therefore, persons living in a dengue endemic area are at risk of encountering secondary infection with other DENV serotypes.DENV is an arbovirus (arthropod-borne virus) that is primarily transmitted between humans and Aedes aegyptim which breed in domestic and peridomestic water containers. A sylvatic cycle (whereby jungle primates and mosquito vectors perpetuate the virus) has been documented in Southeast Asia and West Africa, but it is presently uncertain to what extent this cycle contributes to human infections [5]. It is believed that this virus displays enzootic maintenance cycles that involve Aedes mosquitoes, which breed in tree holes and transmit the virus between mon...

No abstract

No abstract