Human T-lymphotropic virus 1
A strain of PRIMATE T-LYMPHOTROPIC VIRUS 1 isolated from mature T4 cells in patients with T-lymphoproliferation malignancies. It causes adult T-cell leukemia (LEUKEMIA-LYMPHOMA, T-CELL, ACUTE, HTLV-I-ASSOCIATED), T-cell lymphoma (LYMPHOMA, T-CELL), and is involved in mycosis fungoides, SEZARY SYNDROME and tropical spastic paraparesis (PARAPARESIS, TROPICAL SPASTIC).
Paraparesis, Tropical Spastic
A subacute paralytic myeloneuropathy occurring endemically in tropical areas such as the Caribbean, Colombia, India, and Africa, as well as in the southwestern region of Japan; associated with infection by HUMAN T-CELL LEUKEMIA VIRUS I. Clinical manifestations include a slowly progressive spastic weakness of the legs, increased reflexes, Babinski signs, incontinence, and loss of vibratory and position sensation. On pathologic examination inflammatory, demyelination, and necrotic lesions may be found in the spinal cord. (Adams et al., Principles of Neurology, 6th ed, p1239)
Antibodies reactive with the HTLV-I ANTIGENS.
An island in the Greater Antilles in the West Indies. Its capital is Kingston. It was discovered in 1494 by Columbus and was a Spanish colony 1509-1655 until captured by the English. Its flourishing slave trade was abolished in the 19th century. It was a British colony 1655-1958 and a territory of the West Indies Federation 1958-62. It achieved full independence in 1962. The name is from the Arawak Xaymaca, rich in springs or land of springs. (From Webster's New Geographical Dictionary, 1988, p564 & Room, Brewer's Dictionary of Names, 1992, p267)
Human T-lymphotropic virus 2
A strain of PRIMATE T-LYMPHOTROPIC VIRUS 2 that can transform normal T-lymphocytes and can replicate in both T- and B-cell lines. The virus is related to but distinct from HTLV-1.
Gene Products, tax
A genus in the family RETROVIRIDAE consisting of exogenous horizontally-transmitted viruses found in a few groups of mammals. Infections caused by these viruses include human B- or adult T-cell leukemia/lymphoma (LEUKEMIA-LYMPHOMA, T-CELL, ACUTE, HTLV-I-ASSOCIATED), and bovine leukemia (ENZOOTIC BOVINE LEUKOSIS). The type species is LEUKEMIA VIRUS, BOVINE.
Duplex DNA sequences in eukaryotic chromosomes, corresponding to the genome of a virus, that are transmitted from one cell generation to the next without causing lysis of the host. Proviruses are often associated with neoplastic cell transformation and are key features of retrovirus biology.
DNA sequences that form the coding region for at least three proteins which regulate the expression of HUMAN T-LYMPHOTROPIC VIRUS 1 and HUMAN T-LYMPHOTROPIC VIRUS 2. The proteins are p21(x), p27(rex), and p40(tax). The tax (trans-activator x) and rex (regulator x) genes are part of pX but are in overlapping reading frames. X was the original designation for the sequences or region (at that time of unknown function) in the long open reading frame (lor) which is now called pX.
Leukemia-Lymphoma, Adult T-Cell
The quantity of measurable virus in a body fluid. Change in viral load, measured in plasma, is sometimes used as a SURROGATE MARKER in disease progression.
Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.
Acquired Immunodeficiency Syndrome
An acquired defect of cellular immunity associated with infection by the human immunodeficiency virus (HIV), a CD4-positive T-lymphocyte count under 200 cells/microliter or less than 14% of total lymphocytes, and increased susceptibility to opportunistic infections and malignant neoplasms. Clinical manifestations also include emaciation (wasting) and dementia. These elements reflect criteria for AIDS as defined by the CDC in 1993.
Simian T-lymphotropic virus 1
A strain of PRIMATE T-LYMPHOTROPIC VIRUS 2, closely related to the human HTLV-1 virus. The clinical, hematological, and histopathological characteristics of the disease in STLV-infected monkeys are very similar to those of human adult T-cell leukemia. Subgroups include the African green monkey subtype (STLV-I-AGM), for which the nucleotide sequence is 95% homologous with that of HUMAN T-LYMPHOTROPIC VIRUS 1, and the Asian rhesus macaque subtype (STLV-I-MM), for which the nucleotide sequence is 90% homologous with that of HUMAN T-LYMPHOTROPIC VIRUS 1.
Antibodies reactive with the HTLV-II ANTIGENS.
Polymerase Chain Reaction
In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
Primate T-lymphotropic virus 3
Retroviridae Proteins, Oncogenic
Antigens associated with HUMAN T-LYMPHOTROPIC VIRUS 1.
Morphologic alteration of small B LYMPHOCYTES or T LYMPHOCYTES in culture into large blast-like cells able to synthesize DNA and RNA and to divide mitotically. It is induced by INTERLEUKINS; MITOGENS such as PHYTOHEMAGGLUTININS, and by specific ANTIGENS. It may also occur in vivo as in GRAFT REJECTION.
Antigens associated with HUMAN T-LYMPHOTROPIC VIRUS 2.
A French overseas department on the northeast coast of South America. Its capital is Cayenne. It was first settled by the French in 1604. Early development was hindered because of the presence of a penal colony. The name of the country and the capital are variants of Guyana, possibly from the native Indian Guarani guai (born) + ana (kin), implying a united and interrelated race of people. (From Webster's New Geographical Dictionary, 1988, p418 & Room, Brewer's Dictionary of Names, 1992, p195)
Molecular Sequence Data
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
A classification of T-lymphocytes, especially into helper/inducer, suppressor/effector, and cytotoxic subsets, based on structurally or functionally different populations of cells.
Gene Products, env
Gene Products, rex
The type species of ORTHOPOXVIRUS, related to COWPOX VIRUS, but whose true origin is unknown. It has been used as a live vaccine against SMALLPOX. It is also used as a vector for inserting foreign DNA into animals. Rabbitpox virus is a subspecies of VACCINIA VIRUS.
A CELL LINE derived from human T-CELL LEUKEMIA and used to determine the mechanism of differential susceptibility to anti-cancer drugs and radiation.
A critical subpopulation of T-lymphocytes involved in the induction of most immunological functions. The HIV virus has selective tropism for the T4 cell which expresses the CD4 phenotypic marker, a receptor for HIV. In fact, the key element in the profound immunosuppression seen in HIV infection is the depletion of this subset of T-lymphocytes.
A malignant disease of the T-LYMPHOCYTES in the bone marrow, thymus, and/or blood.
The collective name for the islands of the Pacific Ocean northeast of Australia, including NEW CALEDONIA; VANUATU; New Hebrides, Solomon Islands, Admiralty Islands, Bismarck Archipelago, FIJI, etc. Melanesia (from the Greek melas, black + nesos, island) is so called from the black color of the natives who are generally considered to be descended originally from the Negroid Papuans and the Polynesians or Malays. (From Webster's New Geographical Dictionary, 1988, p748 & Room, Brewer's Dictionary of Names, 1992, p344)
Indians, Central American
Human T-lymphotropic virus 3
A strain of PRIMATE T-LYMPHOTROPIC VIRUS 3 that is genetically similar to STLV-3.
Cell Transformation, Viral
Human immunodeficiency virus. A non-taxonomic and historical term referring to any of two species, specifically HIV-1 and/or HIV-2. Prior to 1986, this was called human T-lymphotropic virus type III/lymphadenopathy-associated virus (HTLV-III/LAV). From 1986-1990, it was an official species called HIV. Since 1991, HIV was no longer considered an official species name; the two species were designated HIV-1 and HIV-2.
Gene Expression Regulation, Viral
The expelling of virus particles from the body. Important routes include the respiratory tract, genital tract, and intestinal tract. Virus shedding is an important means of vertical transmission (INFECTIOUS DISEASE TRANSMISSION, VERTICAL).
Amino Acid Sequence
Terminal Repeat Sequences
Nucleotide sequences repeated on both the 5' and 3' ends of a sequence under consideration. For example, the hallmarks of a transposon are that it is flanked by inverted repeats on each end and the inverted repeats are flanked by direct repeats. The Delta element of Ty retrotransposons and LTRs (long terminal repeats) are examples of this concept.
Simian virus 40
Indians, South American
Sensitive assay using radiolabeled ANTIGENS to detect specific ANTIBODIES in SERUM. The antigens are allowed to react with the serum and then precipitated using a special reagent such as PROTEIN A sepharose beads. The bound radiolabeled immunoprecipitate is then commonly analyzed by gel electrophoresis.
Cytopathogenic Effect, Viral
Visible morphologic changes in cells infected with viruses. It includes shutdown of cellular RNA and protein synthesis, cell fusion, release of lysosomal enzymes, changes in cell membrane permeability, diffuse changes in intracellular structures, presence of viral inclusion bodies, and chromosomal aberrations. It excludes malignant transformation, which is CELL TRANSFORMATION, VIRAL. Viral cytopathogenic effects provide a valuable method for identifying and classifying the infecting viruses.
Viruses which lack a complete genome so that they cannot completely replicate or cannot form a protein coat. Some are host-dependent defectives, meaning they can replicate only in cell systems which provide the particular genetic function which they lack. Others, called SATELLITE VIRUSES, are able to replicate only when their genetic defect is complemented by a helper virus.
Viral Regulatory and Accessory Proteins
A broad category of viral proteins that play indirect roles in the biological processes and activities of viruses. Included here are proteins that either regulate the expression of viral genes or are involved in modifying host cell functions. Many of the proteins in this category serve multiple functions.
Repetitive Sequences, Nucleic Acid
Sequences of DNA or RNA that occur in multiple copies. There are several types: INTERSPERSED REPETITIVE SEQUENCES are copies of transposable elements (DNA TRANSPOSABLE ELEMENTS or RETROELEMENTS) dispersed throughout the genome. TERMINAL REPEAT SEQUENCES flank both ends of another sequence, for example, the long terminal repeats (LTRs) on RETROVIRUSES. Variations may be direct repeats, those occurring in the same direction, or inverted repeats, those opposite to each other in direction. TANDEM REPEAT SEQUENCES are copies which lie adjacent to each other, direct or inverted (INVERTED REPEAT SEQUENCES).
The type species of ALPHAVIRUS normally transmitted to birds by CULEX mosquitoes in Egypt, South Africa, India, Malaya, the Philippines, and Australia. It may be associated with fever in humans. Serotypes (differing by less than 17% in nucleotide sequence) include Babanki, Kyzylagach, and Ockelbo viruses.
Gene Products, gag
Proteins coded by the retroviral gag gene. The products are usually synthesized as protein precursors or POLYPROTEINS, which are then cleaved by viral proteases to yield the final products. Many of the final products are associated with the nucleoprotein core of the virion. gag is short for group-specific antigen.
Influenza A Virus, H1N1 Subtype
Cell Line, Transformed
Eukaryotic cell line obtained in a quiescent or stationary phase which undergoes conversion to a state of unregulated growth in culture, resembling an in vitro tumor. It occurs spontaneously or through interaction with viruses, oncogenes, radiation, or drugs/chemicals.
env Gene Products, Human Immunodeficiency Virus
Influenza A Virus, H5N1 Subtype
A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 5 and neuraminidase 1. The H5N1 subtype, frequently referred to as the bird flu virus, is endemic in wild birds and very contagious among both domestic (POULTRY) and wild birds. It does not usually infect humans, but some cases have been reported.
An island republic of the West Indies. Its capital is Roseau. It was discovered in 1493 by Columbus and held at different times by the French and the British in the 18th century. A member of the West Indies Federation, it achieved internal self-government in 1967 but became independent in 1978. It was named by Columbus who discovered it on Sunday, Domingo in Spanish, from the Latin Dominica dies, the Lord's Day. (From Webster's New Geographical Dictionary, 1988, p338 & Room, Brewer's Dictionary of Names, 1992, p151)
Classes of retroviruses for which monkeys or apes are hosts. Those isolated from the West African green monkey and the Asian rhesus macaque monkey are of particular interest because of their similarities to viruses causing cancer and acquired immunodeficiency syndrome (AIDS) in humans.
A genus of Old World monkeys of the subfamily CERCOPITHECINAE, family CERCOPITHECIDAE, that inhabits the mountainous regions of Ethiopia. The genus consists of only one species, Theropithecus gelada.