Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:Q17RS7 (Gen)
 130,125 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Murine monoclonal antibodies (MAbs) gp41-1 (IgG2a) and gp41-2 (IgG1), directed against the envelope glycoprotein of human immunodeficiency virus type 1 (HIV-1), were produced and characterized. These MAbs recognized both gp160 and gp41 and reacted with divergent HIV-1 isolates. Surface binding assays using viable HIV-infected cells indicated that these MAbs were directed against surface-exposed epitopes. Both MAbs caused a reduction in reverse transcriptase activity. Syngeneic monoclonal antiidiotypic antibodies (anti-ids) against gp41-1 were also generated. Six anti-ids (agp41-11 to agp41-16) were selected by ELISA using F(ab')2 fragments of gp41-1; no reaction was observed when fragments from an irrelevant IgG2a MAb were used. Anti-ids were recognized by both gp41-1 and gp41-2 biotinylated MAbs. Competitive ELISA studies suggested that anti-ids were directed against at least three distinct idiotopes on gp41-1. All anti-ids reacted with idiotopes associated with both heavy and light chains and not with separated chains. The binding of MAbs gp41-1 and gp41-2 to HIV-infected cells was inhibited by each anti-id, except for the binding of gp41-2 which was not affected by the presence of agp41-12. Immunization of rabbits with agp41-11 and agp41-13 resulted in an antibody response against recombinant gp160. These studies indicated that these two anti-ids contain a surrogate image of the antigen recognized by gp41-1.
J Gen Virol 1991 Jan
PMID:Monoclonal idiotypic and anti-idiotypic antibodies to human immunodeficiency virus type 1 envelope glycoprotein. 170 62

The C-terminal region of human immunodeficiency virus (HIV) reverse transcriptase (RT) contains the domain responsible for RNase H activity. To determine the importance of this RNase H domain, specific changes in the C-terminal region of a recombinant RT expressed in Escherichia coli were introduced by amino acid substitutions and specific deletions. The enzyme activities of purified wild-type and mutant RT/RNase H proteins, standardized for protein content, were compared by filter assays and thermal inactivation kinetics. A point mutation of His 539----Asn produced an enzyme with a marked thermolabile RNase H function (nine-fold increase in inactivation), whereas RT function was only marginally more labile than that of the wild-type (two-fold). A second mutation, His 539----Asp, impaired both enzyme activities to a similar degree (four- to five-fold). A C-terminal deletion of 19 amino acids (aa) (aa 540 to 558) and a C-terminal truncation of 21 aa (aa 540 to 560) reduced RT as well as RNase H activity. A 130 aa deletion enzyme exhibited no RNase H activity and insufficient RT activity to allow inactivation studies. Two mutants, the 19 aa deletion and His----Asn, were introduced into proviral HIV-1 DNA clones to determine whether changes in enzyme activity, particularly RNase H activity, affected virus infectivity. Both mutants were non-infectious, indicating that the C-terminal 19 to 21 amino acids and His 539 of the RT/RNase H protein are essential for HIV replication. These results are consistent with the assumption that RNase H is essential for the infectivity of HIV-1.
J Gen Virol 1991 Jan
PMID:Mutations within the RNase H domain of human immunodeficiency virus type 1 reverse transcriptase abolish virus infectivity. 170 63

Antibody-reactive peptide scanning (Pepscan) using overlapping nonapeptides and human sera as probes allows the identification of amino acids contributing significantly to antigen-antibody interaction. Five-hundred and two overlapping nonapeptides derived from the human immunodeficiency virus type 2 strain Rod (HIV-2Rod) external envelope glycoprotein gp125 were synthesized to serve as probes for reactivity with eight sera of HIV-2-infected individuals. Fifteen antibody-binding regions were identified, among which two amino-terminal regions [E3, amino acids (aa) 118 to 132; E4, aa 125 to 141] and four carboxy-terminal regions (E11, aa 303 to 324; E12, aa 340 to 358; E14, aa 436 to 452; E15, aa 486 to 507) were the most antigenic. The amino acids in binding sites E3 and E4 were highly variable among simian immunodeficiency virus (SIV), HIV-2 and HIV-1. The antibody-binding domains E14 and E15 were highly conserved among HIV-2 strains (94% and 86% identity of HIV-2Rod to HIV-2Isy and HIV-2NIHZ, respectively). Both domains had more amino acids in common with SIV (88% for E14, 64% for E15) than with HIV-1 (41% for E14, 45% for E15). Epidemiological studies revealed that the sera of African HIV-2-infected individuals bound the E11 and E15 peptides best (31%, 8/26). The sera of African HIV-1-infected individuals showed significant levels of cross-reactivity to the HIV-2 peptides, especially to the E15 peptide, whereas the sera of European HIV-1-infected individuals showed only moderate levels of cross-reactivity. If peptides covering the E15 epitope were used, African HIV-2-positive sera showed only a low level of cross-reactivity (4%) to E15 of HIV-1 and SIV. African HIV-1-positive sera bound the HIV-1 E15 peptide best (81%, 52/64), but showed high levels of cross-reactivity to SIV E15 (17%, 11/64) and HIV-2 E15 (25%, 16/64). European HIV-1-positive sera showed a high level of reactivity of HIV-1 E15 (91%, 50/55) and a low level of cross-reactivity to the HIV-2 (2%, 1/55), and none to the SIV E15 (0/55) peptide. These results indicate that the immunodominant regions of the HIV-2 external envelope (E11 and E15) align with the most immunodominant regions of HIV-1.
J Gen Virol 1991 Jun
PMID:Characterization of human antibody-binding sites on the external envelope of human immunodeficiency virus type 2. 171 Jun 45

Eighteen monoclonal antibodies (MAbs) directed against the purified human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) protein were produced. The antibodies were characterized by competitive ELISAs and Western blot experiments, and with nested, nine amino acid long peptides representing the whole 560 amino acid RT protein. By ELISA, the MAbs react with a minimum of seven epitopes of the protein. Four of the epitopes were located on the N-terminal 51K subunit and the remaining three epitopes were located at the C-terminal end of the protein. Using synthetic peptides, two epitopes at the N-terminal part were located at amino acids 294 to 302 and 350 to 354, respectively, from the N-terminal start of the protein. One epitope was located at amino acids 442 to 450, just after the cleavage site between the N-terminal and C-terminal subunit at position 440. Antibodies located at amino acids 294 to 302 could inhibit the RT enzymic activity of the protein. Two other MAbs, directed at the N-terminal and C-terminal parts of the protein, could also inhibit RT activity.
J Gen Virol 1991 Aug
PMID:Immunological characterization of the human immunodeficiency virus type 1 reverse transcriptase protein by the use of monoclonal antibodies. 171 42

Bovine immunodeficiency virus (BIV) was purified by isodensity centrifugation; viral activities were monitored in gradient fractions using the reverse transcriptase assay and a p26-specific monoclonal antibody ELISA. In the coincident peak fractions (density about 1.17 g/ml) proteins with Mr values of 26K, 17K, 53K, 14K and 100K (with decreasing intensity) were detected by Western blotting using serum of a calf after experimental BIV infection. When 957 randomly collected cattle sera from The Netherlands were tested by indirect immunofluorescence and confirmed using Western blot and/or radioimmunoprecipitation, 1.4% appeared seropositive. Thus BIV infection is not uncommon in one European cattle population.
J Gen Virol 1991 Dec
PMID:Bovine immunodeficiency virus: immunochemical characterization and serological survey. 172 2

Under conditions in which a clonal cell line (M10) isolated from a human T cell lymphotrophic virus type I-transformed MT-4 cell line was completely killed by infection with wild-type human immunodeficiency virus type 1 (HIV-1), equivalent M10 cells survived infection with HIV-1 vif, vpr or vpu mutant virus after transient cytopathic effects. Several cell clones, which were isolated from the proliferating M10 cells after infection with vif and vpu mutant viruses (M10/vif- and M10/vpu-), had heterogeneous HIV-1 phenotypes in terms of HIV-1 antigen expression, their syncytium forming capacity, reverse transcriptase activity and the infectivity of HIV-1 particles produced. When the replication kinetics of the HIV-1 particles produced were assayed in M10 cells, the clones could be classified into three types, i.e. type I producing non-infectious HIV-1, type II producing infectious HIV-1 with low replicative ability and type III producing infectious HIV-1 with a replicative ability similar to that of wild-type HIV-1. HIV-1 major viral cell proteins and virus particle fractions were almost typical in types II and III but not in type I. Electron microscopic examination of particles released by I, II and III clones revealed rare defective, predominantly defective and essentially normal virions, respectively. Northern and Southern blot analyses revealed no apparent deletion in the proviral DNA and mRNA prepared from these clones, except in the case of type I and II clones isolated from M10/vpu- which contained large deletions in the mRNAs for gag and gag-pol proteins. Thus, M10 cells surviving infection with HIV-1 vif or vpu mutants are heterogeneous, persistently expressing HIV-1 antigens and producing non-infectious or less cytopathic virus.
J Gen Virol 1992 Jan
PMID:Cells surviving infection by human immunodeficiency virus type 1: vif or vpu mutants produce non-infectious or markedly less cytopathic viruses. 173 Sep 43

In order to assess the adequacy of learning about the human immunodeficiency virus (HIV) and the acquired immune deficiency syndrome (AIDS) in vocational training for general practice, a postal questionnaire survey was carried out among trainers and their trainees in seven health regions of England and Scotland. A total of 616 trainers (62%) and 538 trainees (58%) responded to the questionnaire asking about their knowledge, skills and attitudes regarding HIV and AIDS. Trainees' principal difficulties with HIV and AIDS resembled those of general practitioners currently in practice. More than 60% of trainees lacked knowledge about HIV and AIDS in babies, 50% would not accept intravenous drug misusers onto their list, only 12% found it easy to discuss sex with homosexual male patients, and only 37% felt able to offer counselling about HIV and AIDS. Trainees who had had a tutorial on HIV and AIDS as part of vocational training were significantly more knowledgeable than the remainder (P less than 0.01). In addition, trainees who found workshops on HIV and AIDS useful were more willing than others to take on drug misusers (P less than 0.05) and more confident in their ability to counsel patients with HIV infection (P less than 0.01). No significant associations were found between the trainers' own knowledge, attitudes and skills regarding HIV and AIDS and those of their trainees. It is concluded that there is a need to improve teaching about HIV and AIDS in vocational training for general practice. All general practitioner trainees should receive a tutorial to update their knowledge about HIV and AIDS, and attend a suitable workshop to challenge unfavourable attitudes and improve confidence in counselling.
Br J Gen Pract 1991 Oct
PMID:AIDS: knowledge, skills and attitudes among vocational trainees and their trainers. 158 62

Monoclonal antibodies (MAbs) 3B7 and 1C11 were produced against the gag gene products of feline immunodeficiency virus (FIV). These MAbs reacted strongly with FIV p24 in Western blots (immunoblots) and recognized p50 with a lower intensity. They specifically bound antigens in the cytoplasm of FIV-infected cells as determined by indirect immunofluorescence and immunocytochemistry. Although neither MAb inhibited viral replication in vitro, they were useful in a simple assay for the detection and quantification of infectious virus and neutralizing antibody activity. The assay utilizes Crandell feline kidney cells and requires 4 days for completion. Neutralizing antibodies in cats were detected 3 to 4 weeks after experimental infection with FIV. Antibody titres progressively increased during the first year of infection reaching high titres which were maintained 2.5 years post-infection. The MAbs produced should be valuable reagents for the monitoring of viral replication in cells or tissues from FIV-infected cats and for other in vitro applications.
J Gen Virol 1991 Mar
PMID:Characterization of two monoclonal antibodies against feline immunodeficiency virus gag gene products and their application in an assay to evaluate neutralizing antibody activity. 184 96

Infection with human herpesvirus 6 (HHV-6) was found to up-regulate expression of human immunodeficiency virus and human T cell leukaemia virus type I (HTLV-I) long terminal repeat sequence (LTR), and herpes simplex virus type 1 (HSV-1) gD chloramphenicol acetyltransferase (CAT) constructs transfected into the T cell line, J. Jhan. Activation by HHV-6 was due to one or more viral proteins produced early in infection and, in the case of the HTLV-I LTR, was synergistic to induction mediated by the HTLV-I tax gene product. Neither the HTLV-I enhancer nor basal promoter elements of the HSV-1 gD gene were essential for activation and no increase in accumulated HTLV-I mRNA was observed due to HHV-6 infection. Induction by HHV-6 was found to be dependent on the reporter construct used, because the CAT gene and, to a lesser extent, the HSV-1 thymidine kinase gene were responsive to HHV-6 infection although no significant activation of growth hormone constructs was observed. Our results bear a strong resemblance to those obtained for the Epstein-Barr virus BMLF1 gene, indicating that the major HHV-6 trans-activator may be a homologue of this gene.
J Gen Virol 1991 May
PMID:Activation of gene expression by human herpesvirus 6 is reporter gene-dependent. 185 12

An ultrastructural study was performed on rabbit epithelial RK-13 cells and CD4+ human T lymphocyte lines infected with various recombinant vaccinia viruses (RVVs) expressing genes of human immunodeficiency virus (HIV): the mature p17 or p24 gag domain alone, the entire or truncated gag gene, the reverse transcriptase domain, or the gag-pol genes with a frameshift mutation. Cells infected with RVVs that produced the gag polyprotein with a predicted Mr of more than 48K showed budding and release of HIV-like particles into the extracellular space. These particles were not observed in cells expressing a truncated gag gene (p17 and p24 regions). Mature HIV-like particles were observed extracellularly when the entire gag gene and the protease region of the pol gene were expressed. In contrast, in cells infected with RVVs that contained the gag-pol gene with a frameshift mutation, neither recognizable budding structures nor extracellular HIV-like particles could be detected. These results suggest that the gag gene, particularly its 3' terminus, is necessary for the assembly of HIV particles. In addition, the protease region of the pol gene seems to be required for morphological maturation of HIV particles, but complete proteolytic cleavage of the gag protein may prevent bud formation.
J Gen Virol 1991 Oct
PMID:Role of the gag and pol genes of human immunodeficiency virus in the morphogenesis and maturation of retrovirus-like particles expressed by recombinant vaccinia virus: an ultrastructural study. 191 28


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>