The envelope protein of hepatitis C virus (HCV) is composed of two membrane-associated glycoproteins, E1 and E2. To obtain HCV E2 protein as a secretory form at a high level, we constructed a recombinant chinese hamster ovary (CHO) cell line expressing a C-terminal truncated E2 (E2t) fused to human growth hormone (hGH), CHO/hGHE2t. The hGHE2t fusion protein was purified from the culture supernatant using anti-hGH mAb affinity chromatography at approximately 80% purity. The purified hGHE2t protein appeared to be assembled into oligomers linked by intermolecular disulfide bond(s) when density gradient centrifugation and SDSpolyacrylamide gel electrophoresis were employed. When the purified fusion protein was used for testing its ability to bind to antibodies specific for HCV by enzymelinked immunosorbent assay, the protein was recognized by antibodies in sera from 90% of HCV-positive patients. Treatment of hGHE2t protein by ␤-mercaptoethanol, but not by heat and SDS, significantly reduced its reactivity to the antibodies of patient sera, suggesting that intermolecular and/or intramolecular disulfide bonds are important for its ability to recognize its specific antibody and that the E2 protein contains discontinuous antigenic epitope(s). Hepatitis C virus (HCV)1 is a major causative agent of posttransfusion and sporadic non-A, non-B hepatitis throughout the world (1, 2). In most cases, the virus appears to cause a persistent infection. Previous studies indicate that the development of chronic liver diseases, cirrhosis, and hepatocellular carcinoma is associated with chronic HCV infection (3).Comparative analyses of the genomes from several HCV strains indicate that HCV is a member of the family Flaviviridae, which includes flaviviruses and pestiviruses (4). The HCV genome is a 9.5-kilobase positive-strand RNA from which a single polypeptide is expressed and processed by cellular and viral proteinases to produce the putative viral structural and nonstructural proteins (4 -6). It was previously shown that structural proteins were composed of the core protein of 18 -22 kDa and two glycosylated envelope proteins, E1 of 31-35 kDa and E2 of 58 -74 kDa (5, 7-11). Although some lymphocyte cell lines have shown to support the limited replication of HCV, there has not been in vitro cell culture system efficiently enough to be used for viral propagation and for detailed virological studies (12). Expression studies using recombinant cDNA templates are the only means for identifying individual HCV proteins and to study their roles in the pathogenesis of HCV infection.The hydrophobicity profile of HCV polyprotein suggested that the HCV E2 protein corresponds to the flavivirus NS1 glycoprotein and the major pestivirus envelope protein gp53/ gp55 (E2; gp53 in bovine viral diarrhea virus and gp55 in hog cholera virus), which were reported to induce protective immunity in experimental animals (13,14). HCV envelope proteins are of considerable interest, because experimentally challenged chimpanzees were either protected or shown to a...

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Work related Musculoskeletal Disorders represent chronic health hazards which are usually appeared in hands, wrists, shoulders, neck, shoulder blade, and back by minutely injuring muscles, joints, blood vessels and nerves caused from excessive use of a specific physical part or muscle(1). The work kinds with especially higher potential of musculoskeletal disorders were simply repeating works, heavy material dealing works, hand tool and various machines operating works, VDT work, various assembling works, wrapping works, and poultry and meat processing work(2). Most musculoskeletal disorders are cumulative trauma disorders, meaning the functional injuries in soft physical tissues like muscular tissues.Production workers in industrial or production sites are much exposed to repetitive motions by performing simple repetitive works, and such work environments may become potential factors to insure body parts. Such discomfort working factors are long term influenced on body parts, especially on upper parts like neck, shoulder, arms. In the physical part long term influenced, the musculoskeletal disorders (MSDs) or the cumulative trauma disorders(CTDs) are created with showing ill symptoms like pain,