Fig.1 HTLV-1 virus structure and genome. (Verdonck, et al., 2007)
Human T-cell leukemia viruses (HTLVs), belonging to the primate T-lymphotropic virus (PTLV) family 1, are complex retroviruses. Of the four species identified so far (HTLV-1, -2, -3, and -4), only HTLV-1 and -2 have been associated with human disease. All HTLV strains are members of the Retroviridae family, genus Deltaretrovirus. HTLV-1 primarily infects CD4+ T cells, inserts its genome into CD4+ T cells, and persists in the host cells as a provirus. HTLV-1 induces chronic, persistent infection in infected individuals, causing two devastating human diseases: adult T-cell leukemia/lymphoma (ATLL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The virus infects up to 10 million people worldwide, with endemic areas of infection in Southwest Japan, Sub-Saharan Africa, South America, the Caribbean, and Middle Eastern and Australo-Melanesian regions.
All four HTLVs have 9 kb genomic structures in common. The structural genes gag, pro, pol, and env, as well as the regulatory genes tax and rex, are found in all four HTLV genotypes. p19 and p24 are the major core proteins of HTLVs. The long terminal repeats (LTRs) of HTLV-3/4 lack three 21-bp repeat sequences compared to HTLV-1/2.
HTLV-1 is primarily linked to human disease. HTLV-2, which is less pathogenic than HTLV-1, generally causes no symptoms. Despite its rarity, HTLV-2 infection can cause neurological problems and/or chronic lung infections. HTLV-3 and HTLV-4 have been described in a forest area in Cameroon as a result of cross-species transmission, with their occurrence restricted to this geographic area, without evidence of pathogenicity and human-to-human transmission.
Fig.2 Schematic representation of HTLV-1 and HTLV-2/3/4 genomes. (Zhang, et al., 2017)
HTLV-1/2 infection is primarily diagnosed through the detection of antibodies in blood or cerebrospinal fluid, though polymerase chain reaction (PCR) testing is also used. Test types detecting anti-HTLV antibodies include the western blot (WB), radioimmunoprecipitation assay (RIA), enzyme-linked immunosorbent assay (ELISA), and line immunoassay; however, the WB test has been found to produce untrustworthy results. WB is primarily used as a confirmatory test following a positive ELISA or other serological test result.
As a leading provider of antibody products, Creative Biolabs specializes in the development and production of antibodies for virology research. We now provide numerous HTLV-1/-2 antibodies targeting various proteins such as tax, gag, gp, env, etc. We also provide a fully comprehensive suite of secondary antibodies and isotype controls to meet your needs. In addition, we offer antibody discovery, engineering, and customized services to meet your specific needs. Please feel free to contact us for further information.
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