实验动物总则

Antibodies elicited during the course of HIV-1 infection can act as a bridge between cytolytic cells and HIV-1-infected cells or other cells that have passively absorbed appropriate HIV-1-antigens. These cytolytic cells cause lysis of the HIV-1-infected cells thereby decreasing vir ...

The immune response to a virus infection involves both nonspecific and specific immune mechanisms. Natural killer (NK) cells are naturally-occurring cytolytic cells capable of lysing various tumor cells and virus-infected cells without previous sensitization or with a require ...

T-helper (Th) lymphocytes play a pivotal role in the immune response to viral pathogens. Understanding of the mechanisms governing the Th response to human immunodeficiency virus type 1 (HIV-1) is key to unveiling the pathogenesis of HIV-1 disease given the primary role the CD4+ T-cell plays as bo ...

Cells within an organism undergo two common forms of cell death. Sudden injury resulting from physical or chemical insult leads to a form of cell death called necrosis. A more subtle programmed form of cell death is termed apoptosis. Apoptosis describes a genetically encoded pathway that plays ...

Infection by the human immunodeficiency virus type 1 (HIV-1) is known to cause a number of changes in the immunophenotypic profile of patients even in the early asymptomatic stages of disease. Such “surrogate markers” are known to correlate with the stage of HIV disease and often are predictive of o ...

The discovery of PCR in 1985 has had an enormous impact on the field of molecular diagnostics. However, an important drawback of solution-phase PCR is that one cannot localize the target of interest to a specific cell type owing to the obligatory tissue destruction required for DNA extraction. This ...

The improvement of instruments and technology enabled the first visualization of viral particles by means of electron microscopy in 1939 (1). In particular, the negative staining technique provided high-resolution electron microscopic images of viral particles This technique ...

Many studies of the molecular biology of hepatitis C virus (HCV) begin by obtaining representative cDNA clones of the viral genome. Most cloning strategies have been devised to deal with the low levels of HCV RNA present in starting material used for RNA isolation and cDNA synthesis. Typical sour ...

HCV and related viruses are now classified as a separate genus in the family Flaviviridae (1), which includes two other genera, Flavivirus (2), and Pestivirus (3). The positive-strand HCV genome RNA is approx 9.4 kb in length and contains a highly conserved 5′ noncoding region followed by a long open rea ...

Hepatitis C virus (HCV) is a positive-stranded RNA virus with a genome size of about 9–10 kb. The genome of this virus encodes a polyprotein with a length of over 3000 amino acids. This polyprotein is cleaved by cellular and viral proteases to generate at least 10 viral gene products. Recent reports have ind ...

The 5′-untranslated region of hepatitis C virus (HCV) has been shown to function as an internal ribosomal entry site, or IRES. The biological function of the HCV IRES has been shown to be essential for initiation of translation of the viral proteins by host ribosomes. With this critical role in HCV repli ...

Heterologous expression systems have been widely used to study hepatitis C virus (HCV) proteins in lieu of an efficient method for establishing HCV infections in cell culture. Studies of HCV polyprotein processing in both mammalian-cell-based and cell-free expression systems have s ...

The hepatitis C virus (HCV) NS3 protein has two distinct biochemical domains. The N-terminal 20 kDa has serine protease activity (see Chapter 31) and the C-terminal 50 kDa has both nucleoside triphosphatase (NTPase) and helicase activities (1–4)

The overexpression of a gene in a heterologous system is often the prelude to or the prerequisite of the elucidation and characterization of a given protein, in particular where the protein is difficult to obtain in sufficient quantity from natural sources. Prokaryotic expression system ...

The hepatitis C virus (HCV) chronically infects approx 4 million patients in the United States alone, and constitutes a major cause of chronic liver disease and hepatocellular carcinoma (1–3). Current antiviral therapies for chronic hepatitis C remain relatively ineffective and have ...

The 3′-end region of the HCV genome is composed of three characteristic elements: conventional 3′-untranslated region, subsequent poly (U) stretch, and a newly identified 3′-terminal sequence named the 3′X tail (1,2). The 3′X tail is thought to be a common structure of the HCV genome, and should have im ...

Hepatitis C virus (HCV) is an encapsidated RNA virus, known to cause devastating liver diseases among the majority of infected individuals (1–3). Latest breakthrough in molecular technology has greatly assisted the advancement in diagnostics and monitoring of virological respon ...

The appropriate formation of specific RNA-protein complexes regulates the normal synthesis, trafficking, and metabolism of intracellular RNA. For RNA viruses, these interactions are essential for replication and translation of the viral genome, as well as packaging of progeny st ...

The liver cell response to hepatitis C, a positive-strand RNA virus of the flaviviridiae, varies considerably from acute disease to chronic hepatitis, and from inapparent infection to cirrhosis. The cellular injury to the host depends on host—viral interactions (Table 1): in general, the m ...

Peripheral blood mononuclear cells (PBMC) contain NK cells, cytotoxic T-lymphocytes (CTL), helper T-cells, and B-cells that respond to viral infection and act to eliminate the virus from infected individuals. CTLs are not only thought to be a major host defense against viral infection, but are ...