RNA transcripts are produced from the 5′ long terminal repeat (LTR) of human immunodeficiency virus type-1 (HIV-1) under the complex control of viral regulatory sequences (1–7). The LTR from a prototypical, laboratory-adapted HIV-1 (HXB2) can be divided into modulatory, core promoter, and t ...
A rather unique feature of the human immunodeficiency virus type-1 (HIV-1) is the structural complexity of the regulatory sequences located in the long-terminal repeat (LTR) promoter region and the number of cellular and viral transcription factors known to interact with these sequen ...
The CCR5 gene encodes a cell-surface chemokine receptor molecule, which serves as a coreceptor for macrophage-tropic strains of HIV-1 (1–3). Mutations in this gene may alter expression or function of the protein product, thereby altering chemokine binding or HIV-1 infection of cells on whi ...
Mutations in a large number of genes have now been identified that ultimately alter the expression or function of the corresponding protein, thereby inducing a particular disease state. These mutations may be found frequently in the disease population, but may also be present to some extent in ...
Infection of CD4+ T-lymphocytes by HIV-1 is initiated by binding of the virus to the CD4 receptor on the lymphocyte surface, followed by fusion of the virus with the cell membrane (1). However, expression of CD4 on certain non-human cells does not render them permissive for HIV-1 entry, suggesting that an ...
From a technical perspective, the introduction and stable expression of exogenes in mammalian cells has advanced rapidly in the last few years. Of the gene transduction methodologies, genetic transfer using retroviruses remains the most popular. There are two components of a generic re ...
Lambda gt11 cDNA libraries are routinely used for gene isolation with antibody and oligomer probes (1–3). Briefly, a recombinant DNA library from different types of cells is constructed in a λgt 11 expression vector. The foreign peptides (antigens) are expressed as a β-galactosidase fusion ...
Telomeres are protein-DNA structures at the ends of all eukaryotic chromosomes that are maintained by a unique ribonucleoprotein known as telomerase. This highly specialized RNA-dependent DNA polymerase provides a critical solution to the end-replication problem by adding TTA ...
The development of vaccines against HIV-1 is currently hindered by incomplete understanding of correlates of protective immunity (1–3). Experiments are necessary to measure immune responses in sufficiently fine detail that specific protective responses can be discerned from t ...
One of the basic requirements for assessing the value of a vaccine candidate is measuring its immunogenicity. This can be done in a variety of ways, with focus on either the humoral or cellular arm of the response, or both. Assay of the humoral response, at minimum, requires the ability to measure changes in a ...
Replication of the human immunodeficiency virus type 1 (HIV-1) is associated with a high degree of viral sequence variation (1) that has been shown to correlate with disease state (2–8). The genetic diversity of the viral swarm within an HIV-1 infected individual is so extensive that this entity has ...
Protective antibody responses against HIV-1 have yet to be identified or determined. HIV-1 envelope gpl20/gp41 is known to exist as a multimer (tetramers or trimers) on the surface of the virion (1–4). A number of immunoassays have been developed to evaluate HIV-1-specific binding antibody re ...
Accurate analyses of antibody specificities and affinities are critical to understanding their role in antibody-mediated neutralization of HIV-1 in vitro and their potential activity against HIV-1 in vivo. Multiple immunologic tools currently exist for measuring antibody- ...
B-cells play an important role in protection against pathogens, and they secrete specific antibodies in serum and mucosal secretions upon antigenic stimulation contributing to immune exclusion and clearance of pathogens. The frequency of antibody forming cells (AFC) in specific o ...
The development of vaccine products for the prevention or treatment of HIV requires accurate assessments of the immune response, both humoral and cellular, so that specific responses can be correlated with efficacy. For assay of humoral immunity, a variety of techniques have been develop ...
The serum titration neutralization assay described in Chapter 33 utilizes a constant amount of infectious virus and indirectly estimates the antibody-mediated reduction in infectious virus by measuring p24 antigen expressed by human peripheral blood mononuclear cells (PBMC ...
Antibodies elicited by passive or active immunization protect against numerous virus diseases. This in vivo protective immunity is often associated with in vitro detection of neutralizing antibodies (NAb) (e.g., polio, measles, influenza, respiratory syncytial virus, yellow f ...
The major route of transmission of the human immunodeficiency virus type 1 (HIV-1) worldwide, like other agents of sexually transmitted disease, is via mucosal surfaces of the genital tract through sexual exposures (1–4). It has been hypothesized that immune responses at these sites may be im ...
Cytotoxic T-cells (CTL) provide the basis of protective immunity in many viral infections by appearing early in the immune response and becoming involved with the elimination of virus by lysis of infected cells. A considerable amount of evidence suggests that CTL may be an especially import ...
The lymphocyte proliferation assay is used as an in vitro surrogate, similar to the in vivo delayed-type hypersensitivity assay, to assess the overall quality and character of the cellular arm of the immune response. The lymphocyte proliferation assay is used to assess congenital immune de ...