Disease relevance of env

• In a new approach to these features, we sequenced the entire env gene of 65 HTLV-I isolates originating from Gabon, French Guiana, West Indies, and Iran, such isolates representing all major HTLVI phylums but the Australo-Melanesian one [1].
• The sequences obtained and all PTLV-I (HTLV-I and STLV-I) env sequences available in the literature were analyzed [1].
• The bulk CTL cultures from WKA/H and DA rats lysed specifically syngeneic SV40-transformed kidney cells infected with recombinant vaccinia viruses (RVV) expressing HTLV-I gag and pX Ag, but not those infected with RVV expressing HTLV-I env Ag or a control vaccinia virus [2].
• In vitro and in vivo anti-human T lymphotropic virus type 1 (HTLV-1) cellular immunity was examined by immunizing rats with a truncated hybrid protein (228 amino acids) of gag and env of HTLV-1 produced by Escherichia coli [3].
• Human T cell lymphotropic virus type I (HTLV-I) gag and env protein-specific antibodies were identified in 6 of 13 patients with essential cryoglobulinemia (EC), by Western blot and radioimmunoprecipitation analysis [4].

High impact information on env

• We have generated a number of mAb against various epitopes on the external envelope glycoprotein, gp46, of human T cell leukemia virus type I (HTLV-I) from a WKA rat immunized with a recombinant vaccinia virus containing the HTLV-I env gene [5].
• Interestingly, these CTL were directed against HTLV-I env and pX gene products [6].
• Immunoblotting and immunoprecipitation of metabolically labeled cell lysates failed to detect synthesis of HTLV-I gag, env, or tat gene products, and cellular RNA dot blot analysis detected varying levels of HTLV-I gene transcripts in only three of the five clones [7].
• The role of four open reading frames (ORFs), located between env and the 3' long terminal repeat of HTLV-1, in mediating disease is not entirely clear [8].
• We describe here an improved system for pseudotyping using a defective human immunodeficiency virus (HIV) type 1 genome in combination with HTLV-1 env in 293T producer cells [9].

Biological context of env

• The antibody titer to HTLV-1 gag and env proteins, as well as the frequency of an antibody response to viral protein p40tax and the titer, increased with increasing viral genome dose [10].
• Expression and immunogenicity in rats of recombinant adenovirus 5 DNA plasmids and vaccinia virus containing the HTLV-I env gene [11].
• The complete human T-cell leukemia virus type I (HTLV-I) env gene was inserted into an expression cassette containing the adenovirus 5 major late promoter (Ad5-MLP) [11].
• Target cells included an HTLV-I-transformed cell line (C91/PL), an HTLV-II-transformed cell line (729pH6neo), and Epstein Barr virus (EBV)-transformed B lymphocytes expressing HTLV-I or -II env or gag gene products after infection with vaccinia/HTLV recombinants [12].
• Nucleotide sequence analyses revealed full homology in the HTLV-I env and LTR regions and in the HTLV-II LTR region between the two samples [13].

Anatomical context of env

• Southern blot analysis using 32P HTLV-I env gene as a probe showed the presence of HTLV-I proviral fragments clonally integrated into the genome of the cell lines [14].
• The polymerase chain reaction (PCR) demonstrated defective proviral genome retaining the HTLV-I pX and env regions in thoracic spinal cord, the level most severely affected [15].
• Analyses of serological human leukocyte antigen (HLA) types indicated that none of the patients possessed a high-risk HLA type known to be associated with adult T-cell leukemia (ATL), whereas they did have high responsive alleles to HTLV-I env similar to that observed in HAM [16].
• HTLV-I mRNA was detected only in lymphocytes and/or lymphoma cells, but the HTLV-I associated antigens (env, gag and pX) were found in histiocytes and endothelial cells, as well as in lymphocytes and/or lymphoma cells [17].
• These results suggest that a single inoculation of DNA expressing HTLV-I env gene can stimulate memory B-cell clones that are able to respond effectively to subsequent encounters with HTLV-I envelope proteins and a specific cellular T helper cell response in mice [18].

Other interactions of env

• DNA preparations of peripheral blood cells, as well as isolated CD4- and CD8-positive cells, were examined for HTLV-I sequences (pol-, env-, gag-, LTR- and tax-region) using polymerase chain reaction (PCR) [19].

Analytical, diagnostic and therapeutic context of env

• Various synthetic peptides corresponding to antigenic regions of HTLV-1 gag and env proteins were used for the screening of antibodies in ELISA [20].
• Eight long-term activated T-cell lines producing HTLV-1 gag and env antigens were established from peripheral blood mononuclear cell cultures of HTLV-1 seropositive individuals, including three from Pygmies [21].
• These results indicate that hyperimmune IgG, but neither heat-inactivated HTLV-I nor env 175-196, were protective against HTLV-I infection induced by blood transfusion [22].
• Expression of HTLV-1 env or pX genes or both was shown in all 12 patients with HU tested by RT-PCR [23].
• A recombinant protein derived from the gp21 region of the human T-cell leukemia virus type I (HTLV-I) env gene was synthesized in Escherichia coli and purified by reversed-phase high-performance liquid chromatography [24].

References