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hiv-2 viral protein x (vpx) ubiquitination is dispensable for ubiquitin ligase interaction and effects on macrophage infection.hiv-2 vpx, a virus-associated accessory protein, is critical for infection of non-dividing myeloid cells. to understand the function of vpx ubiquitination, interaction with an e3 ubiquitin ligase complex, and ability to overcome an inhibition of reverse transcription, we analyzed vpx lysine mutants for their function and replication capability in macrophages. both wt vpx and vpx ta (lysine-less vpx) localized to the cytoplasm and nucleus in hela cells. all hiv-2 vpx lysine mutants were functiona ...201222386056
hiv/simian immunodeficiency virus (siv) accessory virulence factor vpx loads the host cell restriction factor samhd1 onto the e3 ubiquitin ligase complex crl4dcaf1.the sterile alpha motif and hd domain-containing protein-1 (samhd1) inhibits infection of myeloid cells by human and related primate immunodeficiency viruses (hiv and siv). this potent inhibition is counteracted by the vpx accessory virulence factor of hiv-2/sivsm viruses, which targets samhd1 for proteasome-dependent degradation, by reprogramming cellular crl4(dcaf1) e3 ubiquitin ligase. however, the precise mechanism of vpx-dependent recruitment of human samhd1 onto the ligase, and the molecul ...201222362772
human immunodeficiency virus type-2-a milder, kinder virus: an update.human immunodeficiency virus type-2 (hiv-2) belongs to the family retroviridae which is phylogenetically clusters with siv sm from sooty mangabeys. this virus is morphologically similar to human immunodeficiency virus type-1 (hiv-1) but has got only a 40% homology at the nucleotide level. there is a distinct geographical distribution of hiv-2 unlike hiv-1. there are currently eight subtypes/groups identified with subtype/group a responsible for the majority of infections. hiv-2 shows a considera ...201222361754
efficient nef-mediated downmodulation of tcr-cd3 and cd28 is associated with high cd4+ t cell counts in viremic hiv-2 infection.the role of the multifunctional accessory nef protein in the immunopathogenesis of hiv-2 infection is currently poorly understood. here, we performed comprehensive functional analyses of 50 nef genes from 21 viremic (plasma viral load, >500 copies/ml) and 16 nonviremic (<500) hiv-2-infected individuals. on average, nef alleles from both groups were equally active in modulating cd4, tcr-cd3, cd28, mhc-i, and ii cell surface expression and in enhancing virion infectivity. thus, many hiv-2-infected ...201222345473
samhd1 restricts the replication of human immunodeficiency virus type 1 by depleting the intracellular pool of deoxynucleoside triphosphates.samhd1 restricts the infection of dendritic and other myeloid cells by human immunodeficiency virus type 1 (hiv-1), but in lentiviruses of the simian immunodeficiency virus of sooty mangabey (sivsm)-hiv-2 lineage, samhd1 is counteracted by the virion-packaged accessory protein vpx. here we found that samhd1 restricted infection by hydrolyzing intracellular deoxynucleoside triphosphates (dntps), lowering their concentrations to below those required for the synthesis of the viral dna by reverse tr ...201222327569
the human immunodeficiency virus type 1 nef and vpu proteins downregulate the natural killer cell-activating ligand pvr.the human immunodeficiency virus type 1 (hiv-1) evades the immune responses of natural killer (nk) cells through mechanisms that have been partially deciphered. here we show that in hiv-1-infected t lymphocytes, the early viral nef protein downmodulates pvr (cd155, necl-5), a ligand for the activating receptor dnam-1 (cd226) expressed by all nk cells, cd8(+) t cells, and other cell types. this novel nef activity is conserved by nef proteins of laboratory hiv-1 strains (nl4-3, sf2) and of a patie ...201222301152
elicitation of neutralizing antibodies directed against cd4-induced epitope(s) using a cd4 mimetic cross-linked to a hiv-1 envelope glycoprotein.the identification of hiv-1 envelope glycoprotein (env) structures that can generate broadly neutralizing antibodies (bnabs) is pivotal to the development of a successful vaccine against hiv-1 aimed at eliciting effective humoral immune responses. to that end, the production of novel env structure(s) that might induce bnabs by presentation of conserved epitopes, which are otherwise occluded, is critical. here, we focus on a structure that stabilizes env in a conformation representative of its pr ...201222291921
trim5α and species tropism of hiv/siv.human immunodeficiency virus type 1 (hiv-1) infects humans and chimpanzees but not old world monkeys (owms) such as the rhesus monkey (rh) and cynomolgus monkey (cm). hiv-1 efficiently enters cells of owms but encounters a block before reverse transcription. this narrow host range is attributed to a barrier in the host cell. in 2004, the screening of a rh cdna library identified tripartite motif 5α (trim5α) as a cellular antiviral factor. trim5α is one of splicing variants produced by trim5 gene ...201222291694
hiv types, groups, subtypes and recombinant forms: errors in replication, selection pressure and quasispecies.hiv-1 is a chimpanzee virus which was transmitted to humans by several zoonotic events resulting in infection with hiv-1 groups m-p, and in parallel transmission events from sooty mangabey monkey viruses leading to infections with hiv-2 groups a-h. both viruses have circulated in the human population for about 80 years. in the infected patient, hiv mutates, and by elimination of some of the viruses by the action of the immune system individual quasispecies are formed. along with the selection of ...201222286874
origin of decrease in potency of darunavir and two related antiviral inhibitors against hiv-2 compared to hiv-1 protease.acquired immune deficiency syndrome (aids) is caused by the human immunodeficiency virus (hiv) type 1 and 2 (hiv-1 and hiv-2). hiv-1 is observed worldwide while hiv-2 though prevalent in west africa is persistently spreading to other parts of the world. an important target for aids treatment is the use of hiv protease (pr) inhibitors preventing the replication of the virus. in this work, the popular molecular mechanics poisson-boltzmann surface area (mm-pbsa) method has been used to investigate ...201222280246
[research progress of the anti-hiv activity of samhd1].the sam and hd domain containing protein 1 (sterile alpha motif domain and hd domain-containing protein 1, samhd1) is a putative negative regulator of the antiviral innate immune response. it can significantly increase the antiviral immune response, mediates the interferon-induced inflammatory response involved in the host foreign-virus defense system. the early studies have focused on its gene mutations associated with aicardi-goutières syndrome (ags), the latest study found that samhd1 as a po ...201222978176
the vpx lentiviral accessory protein targets samhd1 for degradation in the nucleus.sterile alpha motif domain- and hd domain-containing protein 1 (samhd1) is a deoxynucleoside triphosphohydrolase that restricts the replication of lentiviruses in myeloid cells by hydrolyzing the cellular deoxynucleotide triphosphates to a level below that which is required for reverse transcription. human immunodeficiency virus type 2 (hiv-2) and some simian immunodeficiency viruses (sivs) encode the accessory protein viral protein x (vpx) that counteracts samhd1. vpx recruits samhd1 to a culli ...201222973040
are plasma biomarkers of immune activation predictive of hiv progression: a longitudinal comparison and analyses in hiv-1 and hiv-2 infections?chronic immune activation is a hallmark of hiv infection and has been associated with disease progression. assessment of soluble biomarkers indicating immune activation provide clues into pathogenesis and hold promise for the development of point-of-care monitoring of hiv in resource-poor-settings. their evaluation in cohort resources is therefore needed to further their development and use in hiv research.201222970212
epitope mapping of broadly neutralizing hiv-2 human monoclonal antibodies.recent studies have shown that natural infection by hiv-2 leads to the elicitation of high titers of broadly neutralizing antibodies (nabs) against primary hiv-2 strains (t. i. de silva, et al., j. virol. 86:930-946, 2012; r. kong, et al., j. virol. 86:947-960, 2012; g. ozkaya sahin, et al., j. virol. 86:961-971, 2012). here, we describe the envelope (env) binding and neutralization properties of 15 anti-hiv-2 human monoclonal antibodies (mabs), 14 of which were newly generated from 9 chronicall ...201222933274
association of soluble cd14 and inflammatory biomarkers with hiv-2 disease progression.human immunodeficiency virus type 2 (hiv-2) infection is characterized by a slower progression than hiv type 1. it is not known whether markers of inflammation such as high-sensitivity c-reactive protein (hscrp), interleukin 6 (il-6), and soluble cd14 (scd14) may predict disease progression among hiv-2 patients.201222911639
samhd1-dependent and -independent functions of hiv-2/siv vpx protein.both human immunodeficiency virus (hiv) and simian immunodeficiency virus (siv) encode a unique set of accessory proteins that enhance viral replication in the host. two similar accessory proteins, vpx and vpr, are encoded by hiv-2. in contrast, hiv-1 encodes vpr but not vpx. recent studies have indicated that vpx counteracts a particular host restriction factor, thereby facilitating reverse transcription in myeloid cells such as monocyte-derived macrophages and monocyte-derived dendritic cells. ...201222908011
the role of raltegravir in the treatment of hiv-2 infections: evidence from a case series.we describe five patients with hiv-2 infection (four antiretroviral-experienced and one antiretroviral-naive) treated with a regimen containing raltegravir. all responded to treatment as demonstrated by viral load and cd4(+) t-cell count monitoring. our series confirms the clinical effectiveness of raltegravir in hiv-2-infected patients when given with other antiretrovirals to which the virus is susceptible.201222892365
validation for clinical use of a novel hiv-2 plasma rna viral load assay using the abbott m2000 platform.optimal care of persons infected with human immunodeficiency virus type 2 (hiv-2) requires an accurate assessment of hiv-2 plasma viral load (vl), but no clinically approved quantitative hiv-2 rna vl assay exists.201222832059
an analog of the natural steroidal alkaloid cortistatin a potently suppresses tat-dependent hiv transcription.the human immunodeficiency virus type 1 (hiv) tat protein, a potent activator of hiv gene expression, is essential for integrated viral genome expression and represents a potential antiviral target. tat binds the 5'-terminal region of hiv mrna's stem-bulge-loop structure, the transactivation-responsive (tar) element, to activate transcription. we find that didehydro-cortistatin a (dca), an analog of a natural steroidal alkaloid from a marine sponge, inhibits tat-mediated transactivation of the i ...201222817991
inhibition of hiv-1 disease progression by contemporaneous hiv-2 infection.progressive immune dysfunction and the acquired immunodeficiency syndrome (aids) develop in most persons with untreated infection with human immunodeficiency virus type 1 (hiv-1) but in only approximately 20 to 30% of persons infected with hiv type 2 (hiv-2); among persons infected with both types, the natural history of disease progression is poorly understood.201222808957
a novel dcaf1-binding motif required for vpx-mediated degradation of nuclear samhd1 and vpr-induced g2 arrest.hiv-2 and closely related siv vpx proteins are essential for viral replication in macrophages and dendritic cells. vpx hijacks dcaf1-ddb1-cul4 e3 ubiquitin ligase to promote viral replication. dcaf1 is essential for cell proliferation and embryonic development and is responsible for the polyubiquitination of poorly defined cellular proteins. how substrate receptors recruit the dcaf1-containing e3 ubiquitin ligase to induce protein degradation is still poorly understood. here we identify a highly ...201222776683
enhanced anti-hiv efficacy of indinavir after inclusion in cd4-targeted lipid nanoparticles.combination drug therapy has reduced plasma hiv to undetectable levels; however, drug-sensitive virus persists in patients' lymphoid tissue. we have reported significant lymphoid tissue drug localization with indinavir-associated lipid nanoparticles (lnps). our current objective is to evaluate whether additional enhancement is achievable by targeting these particles to cd4-hiv host cells.201222743598
synthesis, crystal structure and anti-hiv activity of 2-adamantyl/adamantylmethyl-5-aryl-1,3,4-oxadiazoles.two series of 2-adamantyl/adamantylmethyl-5-aryl-1,3,4-oxadiazoles (4a-l and 5a-l) were synthesized by cyclodehydration of adamantan-1-carboxylic acid/adamantylacetic acid with various aryl hydrazides (3a-l) in the presence of pocl(3). the synthesis was supported by spectroanalytical techniques and verified further by crystal structure determination of compounds 4e and 5k. the synthesized compounds were screened for their inhibitory activity against hiv-1 and hiv-2 in mt-4 cells. compound 5b exh ...201222741800
three main mutational pathways in hiv-2 lead to high-level raltegravir and elvitegravir resistance: implications for emerging hiv-2 treatment regimens.human immunodeficiency virus type 2 (hiv-2) is intrinsically resistant to non-nucleoside reverse transcriptase inhibitors and exhibits reduced susceptibility to several of the protease inhibitors used for antiretroviral therapy of hiv-1. thus, there is a pressing need to identify new classes of antiretroviral agents that are active against hiv-2. although recent data suggest that the integrase strand transfer inhibitors raltegravir and elvitegravir may be beneficial, mutations that are known to ...201223028968
synthesis and evaluation of novel 4-substituted styryl quinazolines as potential antimicrobial agents.in an attempt to afford possible antibacterial and anti-human immunodeficiency virus (hiv) agents, a series of 22 novel styryl quinazoline-based heterocyclic entities were designed and synthesized. various substituted aryl urea and thiourea cores were incorporated at position 4 of quinazoline, followed by styrylation of position 2, aiming at an augmented biological potential. the synthesized compounds were well characterized through ir, (1) h nmr, (13) c nmr and elemental analyses. all compounds ...201223018557
resistance to antibody neutralization in hiv-2 infection occurs in late stage disease and is associated with x4 tropism.to characterize the nature and dynamics of the neutralizing antibody (nab) response and escape in chronically hiv-2 infected patients.201223151495
lack of evidence of simian immunodeficiency virus infection among nonhuman primates in taï national park, côte d'ivoire: limitations of noninvasive methods and siv diagnostic tools for studies of primate retroviruses.it is now well established that the human immunodeficiency viruses, hiv-1 and hiv-2, are the results of cross-species transmissions of simian immunodeficiency viruses (siv) naturally infecting nonhuman primates in sub-saharan africa. sivs are found in many african primates, and humans continue to be exposed to these viruses by hunting and handling primate bushmeat. sooty mangabeys (cercocebus atys) and western red colobus (piliocolobus badius badius) are infected with siv at a high rate in the t ...201123950618
photoinactivation of cell-free human immunodeficiency virus by hematoporphyrin monomethyl ether.human immunodeficiency virus (hiv) particles that remain in the blood of patients are frequently ignored as targets for aids treatment. we therefore investigated the use of photodynamic therapy (pdt) with hematoporphyrin monomethyl ether (hmme) as a means of inactivating cell-free hiv in vitro. virus particles including hiv-1(iiib), resistant hiv-1 variants, hiv-1 clinical variants, and hiv-2 variants were incubated with hmme for 40 min, followed by irradiation with a 630-nm semiconductor laser ...201122045116
exploring virus relationships based on virus-host protein-protein interaction network.currently, several systems have been proposed to classify viruses and indicate the relationships between different ones, though each system has its limitations because of the complexity of viral origins and their rapid evolution rate. we hereby propose a new method to explore the relationships between different viruses.201122784617
spontaneous gastric carcinomas in sooty mangabeys (cercocebus atys).sooty mangabeys (cercocebus atys) are native to west africa and are a natural host of siv, which is implicated in the origin of hiv2. they have been used in studies of aids pathogenesis, leprosy, immune responses, reproductive biology, and behavior. spontaneous tumors have rarely been reported in this species. however, we noted spontaneous gastric carcinomas in 8 sooty mangabeys. four male and 4 female mangabeys had mild to severe chronic weight loss, with abdominal distention in 5 of 8 animals. ...201122330580
long-lasting persistence of integrase resistance mutations in hiv-2-infected patients after raltegravir withdrawal.little is known in hiv-2 infection about the kinetics of disappearance of raltegravir (ral)-resistant virus after ral withdrawal.201121900727
human immunodeficiency virus (hiv) types western blot (wb) band profiles as potential surrogate markers of hiv disease progression and predictors of vertical transmission in a cohort of infected but antiretroviral therapy naïve pregnant women in harare, zimbabwe.expensive cd4 count and viral load tests have failed the intended objective of enabling access to hiv therapy in poor resource settings. it is imperative to develop simple, affordable and non-subjective disease monitoring tools to complement clinical staging efforts of inexperienced health personnel currently manning most healthcare centres because of brain drain. besides accurately predicting hiv infection, sequential appearance of specific bands of wb test offers a window of opportunity to dev ...201121211021
a highly sensitive and specific time resolved fluorometric bridge assay for antibodies to hiv-1 and -2.this study addresses the continuing need to develop human immunodeficiency virus-1 (hiv-1) and hiv-2 immunoassays with increased sensitivity. two chimeric antigens, r-hiv-1env, incorporating immunoreactive regions of hiv-1 glycoprotein (gp) 120 and gp41, and r-hiv-2env, incorporating hiv-2 gp125 and gp36, and their corresponding in vivo biotinylated versions, r-bio-hiv-1env and r-bio-hiv-2env, were expressed in escherichia coli and purified by single step affinity chromatography. these antigens ...201121232554
synthesis and biological evaluation of novel 5-alkyl-2-arylthio-6-((3,4-dihydroquinolin-1(2h)-yl)methyl)pyrimidin-4(3h)-ones as potent non-nucleoside hiv-1 reverse transcriptase inhibitors.a series of novel s-dabo analogues of 5-alkyl-2-arylthio-6-((3,4-dihydroquinolin-1(2h)-yl)methyl)pyrimidin-4(3h)-ones were synthesized and evaluated as inhibitors of human immunodeficiency virus type-1 (hiv-1). among them, the most potent hiv-1 inhibitors were compounds 6c1,6c6, and 6b1 (ec(50)=0.24 -¦ 0.05, 0.38 -¦ 0.13, 0.39 -¦ 0.05 ++m, respectively), which possess improved or similar hiv-1 inhibitory activity compared with nevirapine (nvp) (ec(50)=0.21 ++m) and delavirdine (dlv) (ec(50)=0.32 ...201121683601
vpx relieves inhibition of hiv-1 infection of macrophages mediated by the samhd1 protein.macrophages and dendritic cells have key roles in viral infections, providing virus reservoirs that frequently resist antiviral therapies and linking innate virus detection to antiviral adaptive immune responses. human immunodeficiency virus 1 (hiv-1) fails to transduce dendritic cells and has a reduced ability to transduce macrophages, due to an as yet uncharacterized mechanism that inhibits infection by interfering with efficient synthesis of viral complementary dna. in contrast, hiv-2 and rel ...201121720370
fiv diversity: fiv(ple) subtype composition may influence disease outcome in african lions.feline immunodeficiency virus (fiv) infects domestic cats and at least 20 additional species of non-domestic felids throughout the world. strains specific to domestic cat (fiv(fca)) produce aids-like disease progression, sequelae and pathology providing an informative model for hiv infection in humans. less is known about the immunological and pathological influence of fiv in other felid species although multiple distinct strains of fiv circulate in natural populations. as in hiv-1 and hiv-2, mu ...201121723622
formulation, in vitro and in vivo pharmacokinetics of anti-hiv vaginal bioadhesive gel.inexpensive and female-controlled pre-exposure prophylaxis strategies to prevent mucosal transmission of the virus, is urgently needed with the rising prevalence of human immunodeficiency virus (hiv-1 and hiv2) infections in women. zidovudine-loaded bioadhesive vaginal gel may become one of the very useful strategies, as it can be used not only for controlled release but also for enhancing bioavailability. drug delivery through vaginal gel is a promising area for continued research with the aim ...201121731351
Immune reconstitution and inflammatory syndrome due to disseminated tuberculosis in a case of human immunodeficiency virus 2 infection.We present a case of human immunodeficiency virus 2 (HIV- 2) infection with acquired immune deficiency syndrome with immune reconstitution and inflammatory syndrome due to disseminated tuberculosis. We address here the drug interactions between antiretroviral therapy and antituberculous treatment (ATT), choice of ATT, and duration of ATT when rifampicin is omitted as in our case. Though this problem is encountered rarely, we felt that it is important to report the issue to counter drug resistanc ...201121713047
vpx rescues hiv-1 transduction of dendritic cells from the antiviral state established by type 1 interferon.vpx is a virion-associated protein encoded by sivsm, a lentivirus endemic to the west african sooty mangabey (cercocebus atys). hiv-2 and sivmac, zoonoses resulting from sivsm transmission to humans or asian rhesus macaques (macaca mulatta), also encode vpx. in myeloid cells, vpx promotes reverse transcription and transduction by these viruses. this activity correlates with vpx binding to dcaf1 (vprbp) and association with the ddb1/rbx1/cul4a e3 ubiquitin ligase complex. when delivered experimen ...201121696578
Elucidation of the time course of adenosine deaminase APOBEC3G and viral infectivity factor vif in HIV-2(287) -infected infant macaques.Background Although the interactions of cellular cytidine deaminase A3G and viral infection factor (vif) of human immunodeficiency virus (HIV) were reported, regulation of A3G after in vivo HIV infection and disease progression is not known. Methods Time courses of plasma virus, CD4(+) T lymphocyte Macaca levels, and concentrations of A3G and vif transcripts were determined in infant macaques infected with HIV-2(287) . These in vivo results were compared with those collected in vitro in HIV-2 ...201122017399
Antiviral interactions of combinations of highly potent 2,4(1H,3H)-pyrimidinedione congeners and other anti-HIV agents.Structure-activity relationship evaluation of seventy-four 2,4(1H,3H)-pyrimidinedione derivatives identified seven lead compounds based on anti-HIV-1 potency, extended range of action to include HIV-2, virus entry inhibition, reverse transcriptase inhibition, and lack of cytotoxicity to human cells. The selected pyrimidinedione congeners are highly active inhibitors of HIV-1 with EC(50) values ranging from 0.6 to 2 nM in CEM-SS cells infected with laboratory derived viruses, 11-20 nM in fresh hu ...201122036651
antibody-mediated enhancement of hiv-1 and hiv-2 production from bst-2/tetherin-positive cells.bst-2/cd317/hm1.24/tetherin is a b-cell antigen overexpressed on the surface of myeloma cell lines and on neoplastic plasma cells of patients with multiple myeloma. antibodies to bst-2 are in clinical trial for the treatment of multiple myeloma and are considered for the treatment of solid tumors with high bst-2 antigen levels. functionally, bst-2 restricts the secretion of retroviruses, including human immunodeficiency virus type 1, as well as members of the herpesvirus, filovirus, and arenavir ...201121917971
geographic, genetic and functional diversity of antiretroviral host factor trimcyp in cynomolgus macaque (macaca fascicularis).the antiretroviral factor trim5 gene-derived isoform, trimcyp, was found in at least three species of old world monkey, rhesus (macaca mulatta), pig-tailed (macaca nemestrina), and cynomolgus macaques (macaca fascicularis). although the frequency of trimcyp has been well studied in rhesus and pig-tailed macaques, the frequency and prevalence of trimcyp in the cynomolgus macaque remain to be definitively elucidated. here, we studied the geographic and genetic diversity of trim5α/trimcyp in cynomo ...201122113010
susceptibility of hiv type 2 primary isolates to ccr5 and cxcr4 monoclonal antibodies, ligands, and small molecule inhibitors.abstract human immunodeficiency virus (hiv) entry into susceptible cells involves the interaction between viral envelope glycoproteins with cd4 and a chemokine receptor (coreceptor), namely ccr5 and cxcr4. this interaction has been studied to enable the discovery of a new class of antiretroviral drugs that targets the envelope glycoprotein-coreceptor interaction. however, very few data exist regarding hiv-2 susceptibility to these coreceptor inhibitors. with this work we aimed to identify this ...201121902586
How Samhd1 changes our view of viral restriction.Recent studies have uncovered sterile alpha motif and HD domain 1 (SAMHD1) as the restriction factor that blocks HIV-1 replication in myeloid cells. In contrast to previously identified HIV-1 restriction factors, SAMHD1 does not meet a countermeasure developed by HIV-1. However, HIV-2 and certain simian immunodeficiency virus (SIV) strains express the auxiliary protein Vpx that potently blocks SAMHD1. It is therefore perplexing why this function has been lost or not acquired during the course of ...201122177690
A whole genome screen for HIV restriction factors.ABSTRACT:201122082156
samhd1-deficient cd14+ cells from individuals with aicardi-goutières syndrome are highly susceptible to hiv-1 infection.myeloid blood cells are largely resistant to infection with human immunodeficiency virus type 1 (hiv-1). recently, it was reported that vpx from hiv-2/sivsm facilitates infection of these cells by counteracting the host restriction factor samhd1. here, we independently confirmed that vpx interacts with samhd1 and targets it for ubiquitin-mediated degradation. we found that vpx-mediated samhd1 degradation rendered primary monocytes highly susceptible to hiv-1 infection; vpx with a t17a mutation, ...201122174685
PD 404,182 is a virucidal small molecule that disrupts hepatitis C virus and human immunodeficiency virus.We describe a virucidal small molecule, PD 404,182, effective against hepatitis C virus (HCV) and human immunodeficiency virus (HIV). The median IC(50) values for the antiviral effect of PD 404,182 against HCV and HIV in cell culture are 11 µM and 1 µM, respectively. The antiviral activity of PD 404,182 is due to physical disruption of virions that is accompanied to varying degrees (depending on the virus and exposure temperature/time) by release of viral nucleic acids into the surrounding mediu ...201122083468
Synthesis and Anti-HIV Activity of Aryl-2-[(4-cyanophenyl)amino]-4-pyrimidinone hydrazones as Potent Non-nucleoside Reverse Transcriptase Inhibitors.A series of novel diarylpyrimidines (DAPYs) with a ketone hydrazone substituent on the methylene linker between the pyrimidine nucleus and the aryl moiety at the C-4 position were synthesized, and their antiviral activity against human immunodeficiency virus (HIV)-1 in MT-4 cells was evaluated. Most compounds of this class exhibited excellent activity against wild-type HIV-1, with EC(50) values in the range of 1.7-13.2 nM. Of these compounds, 2-bromophenyl-2-[(4-cyanophenyl)amino]-4-pyrimidinon ...201121990112
isolated anti-hbc-igm antibody among blood donors in the semi-arid region of nigeria.laboratory screening for the diagnosis of hepatitis b virus (hbv) infection in blood donors currently consists of testing for hepatitis b surface (hbsag) antigen alone. the prevalence of isolated anti-hbc-igm is not yet known in the semi arid region of nigeria. the major objective of this study was to determine the sero-prevalence of antibody to hepatitis b core antigen (anti-hbc-igm) and other infectious agent markers; hbsag, hcv, hiv and syphilis among blood donors in the north eastern region ...201122129677
emergence of hbv resistance to lamivudine (3tc) in hiv/hbv co-infected patients in the gambia, west africa.abstract: background: lamivudine (3tc) is a potent inhibitor of both hepatitis b virus (hbv) and human immunodeficiency virus (hiv) replication and is part of first-line highly active antiretroviral therapy (haart) in the gambia. unfortunately, the effectiveness of 3tc against hbv is limited by the emergence of resistant strains. aim: the aim of this retrospective study was to characterise 3tc-resistant mutations in hbv from co-infected patients receiving haart, by generating hbv polymerase se ...201122195774
tetherin antagonism by primate lentiviral nef proteins.the multifunctional nef protein of primate lentiviruses is commonly considered an early viral factor that downmodulates various receptors from the cell surface and modulates several signaling pathways to facilitate viral immune evasion and to render the cell conducive for viral replication. however, nef also acts during the late stages of infection, e.g. by increasing the infectivity of progeny virions. just recently, it has become clear that many primate lentiviruses that have been detected in ...201122103835
transfusion transmitted infections - a retrospective analysis from the national blood transfusion service in eritrea.the emergence of transfusion transmitted infection (tti) especially hiv/aids has created a huge obstacle in ensuring blood safety. to assess the situation in eritrea, we carried out a retrospective study of 29,501 blood donors for the prevalence of tti's i.e. hiv, hbv, hcv and syphilis.201122145069
the phylogeographic footprint of colonial history in the global dispersal of hiv-2 group a.hiv-2 emerged in west africa and has further spread to countries that share socio-historical ties with this region. however, viral origins and dispersal patterns at a global scale remain poorly understood. here, we adopt a bayesian phylogeographic approach to investigate the spatial dynamics of hiv-2 group a (hiv-2a) using a collection of 305 partial pol and 237 partial env sequences sampled throughout 18 countries worldwide. we extend phylogenetic diffusion models that simultaneously draw infor ...201122190015
Frequency of human immunodeficiency virus type-2 in hiv infected patients in Maputo City, Mozambique.The HIV/AIDS pandemic is primarily caused by HIV-1. Another virus type, HIV-2, is found mainly in West African countries. We hypothesized that population migration and mobility in Africa may have facilitated the introduction and spreading of HIV-2 in Mozambique. The presence of HIV-2 has important implications for diagnosis and choice of treatment of HIV infection. Hence, the aim of this study was to estimate the prevalence of HIV-2 infection and its genotype in Maputo, Mozambique.HIV-infected i ...201121849066
comparative analysis of transduced primary human dendritic cells generated by the use of three different lentiviral vector systems.lentiviral gene transfer vectors are suitable for genetically modifying non-cycling primary human cells. in this study, we analyzed transduced human dendritic cells (dc) generated by the use of three different gfp-encoding lentiviral vectors, hiv-2 rod a δenv-gfp (rod a), sivsmm pbj δe egfp (pbj), and sivmac δe egfp (sivmac). cd14+ monocytes were isolated from buffy coat, transduced, and differentiated to immature and mature dc. cytofluometric analysis of dc revealed high transduction efficienci ...201120938757
detection, quantification, and characterisation of hiv/siv.selected techniques for the detection, quantification, and characterisation of hiv1, hiv2, and siv, as applied to diagnostic and research purposes, are described. representative nucleic acid testing protocols including nested pcr, rt-pcr, and quantitative real-time pcr, as well as protocols based on virus infectivity, are presented.201121116800
compensatory changes in the cytoplasmic tail of gp41 confer resistance to tetherin/bst-2 in a pathogenic nef-deleted siv.tetherin (bst-2 or cd317) is an interferon-inducible transmembrane protein that inhibits virus release from infected cells. whereas hiv-1 vpu and hiv-2 env counteract human tetherin, most sivs use nef to antagonize the tetherin proteins of their nonhuman primate hosts. here, we show that compensatory changes in the cytoplasmic domain of siv gp41, acquired by a nef-deleted virus that regained a pathogenic phenotype in infected rhesus macaques, restore resistance to tetherin. these changes facilit ...201121238946
the antiviral spectra of trim5a orthologues and human trim family proteins against lentiviral production.rhesus monkey trim5a (trim5arh) recognizes the incoming hiv-1 core through its c-terminal b30.2(pryspry) domain and promotes its premature disassembly or degradation before reverse transcription. previously, we have shown that trim5arh blocks hiv-1 production through the n-terminal rbcc domain by the recognition of gag polyproteins. although all trim family proteins have rbcc domains, it remains elusive whether they possess similar late-restriction activities.201121264255
evolutionary and structural features of the c2, v3 and c3 envelope regions underlying the differences in hiv-1 and hiv-2 biology and infection.unlike in hiv-1 infection, the majority of hiv-2 patients produce broadly reactive neutralizing antibodies, control viral replication and survive as elite controllers. the identification of the molecular, structural and evolutionary footprints underlying these very distinct immunological and clinical outcomes may lead to the development of new strategies for the prevention and treatment of hiv infection.201121283793
human immunodeficiency virus type 1 and related primate lentiviruses engage clathrin through gag-pol or gag.the gag-pol polyprotein of human immunodeficiency virus type 1 (hiv-1) is not required for efficient viral particle production. however, premature termination codons in pol, particularly in the integrase (in)-coding region, can markedly impair hiv-1 particle formation, apparently due to the premature activation of the viral protease (pr). we now report that the in domain of gag-pol is required for the incorporation of clathrin into hiv-1 virions. significantly, pr-dependent effects of point muta ...201121289110
human immunodeficiency virus type 2 in two saudi families.human immunodeficiency virus type 2 (hiv-2), the second retrovirus that causes the acquired immune deficiency syndrome (aids) in humans, is limited in its distribution to west africa. we report cases in two saudi families with hiv-2 infection and aids, resulting in death of the index cases-the husbands, while the wives and a daughter were maintained on antiretroviral therapy. when hiv viral loads were undetectable in initial assays, further testing confirmed the presence of hiv-2. in the first f ...201121293067
false-positive human immunodeficiency virus enzyme immunoassay results in pregnant women.examine whether false-positive hiv enzyme immunoassay (eia) test results occur more frequently among pregnant women than among women who are not pregnant and men (others).201121304592
an underestimated lentivirus model: what can hiv-2 research contribute to the development of an effective hiv-1 vaccine?the development of an hiv-1 vaccine that would be effective against all existing subtypes and circulating recombinant forms remains one of the great scientific and public health challenges of our generation. one of the major barriers to hiv-1 vaccine development is a lack of understanding of the correlates of protective immunity against the virus. in this context, research has focused on the rare phenomenon of spontaneous control of hiv-1 infection, in groups referred to as 'long-term nonprogres ...201121342067
update on human immunodeficiency virus (hiv)-2 infection.infection with human immunodeficiency virus type 2 (hiv-2) occurs mainly in west africa, but an increasing number of cases have been recognized in europe, india, and the united states. in this era of global integration, clinicians must be aware of when to consider the diagnosis of hiv-2 infection and how to test for this virus. although there is debate regarding when therapy should be initiated and which regimen should be chosen, recent trials have provided important information on treatment opt ...201121367732
the performance of the vikia(®) hiv1/2 rapid test-evaluation of the reliability and sensitivity.the use of rapid human immunodeficiency virus (hiv) antibody tests can help reduce the number of individuals positive for hiv who are unaware of their infection. although several studies have demonstrated that the sensitivity and specificity of rapid hiv tests are comparable to those of enzyme immunoassays, none have addressed the rapidity with which these tests can yield a result and the reliability of such results. in this study, we investigated the performance of vikia(®) hiv1/2 rapid tests r ...201121419168
association between peripheral ?d t-cell profile and disease progression in individuals infected with hiv-1 or hiv-2 in west africa.human gammadelta (?d) t cells play an important role in protective immunity in hiv-1 and simian immunodeficiency virus infection; their role in hiv-2 infection is unknown.201121423026
neurologic manifestations of human immunodeficiency virus-2: dementia, myelopathy, and neuropathy in west africa.while well documented in human immunodeficiency virus (hiv)-1, neurologic sequelae have not been systematically evaluated in hiv-2. after excluding for confounding comorbidities, 67 individuals from a rural cohort in guinea-bissau (22 hiv-2 participants, 45 seronegative controls) were evaluated. hiv?+?individuals were divided into cd4?<?350 and cd4?=?350 for analysis. hiv-associated neurocognitive disorders (hand), assessed by the international hiv dementia scale (ihds), distal sensory polyneuro ...201121424866
a case of italian hiv-2 infection: a genetic analysis.human immunodeficiency virus type 2 (hiv-2), originally restricted to western africa is now spreading to european western countries because of migration from endemic areas. therefore, it is mandatory to enforce the surveillance and improve the diagnostics of this neglected infection. in this report, we describe a case of hiv-2 infection affecting an italian citizen along with 3 cases from india. phylogenetic analysis showed that the viral strain identified in the italian patient clustered with a ...201121453133
induction of antibodies binding to the membrane proximal external region of gp36 of hiv-2.objective: the ability to induce neutralizing antibodies may be the most important feature of an antiretroviral vaccine, preventing infection of target cells and subsequent integration of the virus into the cellular genome where the virus may persist. broadly neutralizing antibodies directed against conserved epitopes in the membrane proximal external region (mper) of the transmembrane envelope (tm) protein gp41 of hiv-1 such as the monoclonal antibodies (mab) 2f5 and mab 4e10 have been found in ...201121454955
virucidal activity of the dendrimer microbicide spl7013 against hiv-1.topical microbicides for use by women to prevent the transmission of human immunodeficiency virus (hiv) and other sexually transmitted infections are urgently required. dendrimers are highly branched nanoparticles being developed as microbicides. spl7013 is a dendrimer with broad-spectrum activity against hiv type i (hiv-1) and -2 (hiv-2), herpes simplex viruses type-1 (hsv-1) and -2 (hsv-2) and human papillomavirus. spl7013 [3% (w/w)] has been formulated in a mucoadhesive carbopol gel (vivagel® ...201121459115
[characteristics of antiretroviral drugs.]as of november 2010, a total of 22 antiretroviral agents are marketed in spain. these agents are divided into 6 classes according to their mechanism of action: 1) nucleos(t)ide reverse transcriptase inhibitors (nrti) (abacavir, didanosine, emtricitabine, stavudine, lamivudine, zidovudine, and tenofovir), 2) non-nucleoside reverse transcriptase inhibitors (nnrti) (efavirenz, etravirine, and nevirapine), 3) protease inhibitors (pi) (atazanavir, darunavir, fosamprenavir, indinavir, lopinavir, nelfi ...201121531048
crystal structure of the hiv-2 neutralizing fab fragment 7c8 with high specificity to the v3 region of gp125.7c8 is a mouse monoclonal antibody specific for the third hypervariable region (v3) of the human immunodeficiency virus type 2 (hiv-2)-associated protein gp125. the three-dimensional crystal structure of the fab fragment of 7c8, determined to 2.7 å resolution, reveals a deep and narrow antigen-binding cleft with architecture appropriate for an elongated epitope. the highly hydrophobic cleft is bordered on one side by the negatively charged second complementarity determining region (cdr2) and the ...201121541316
selective inhibition of human immunodeficiency virus type 1 (hiv-1) by a novel family of tricyclic nucleosides.nucleoside 1, with an unusual tricyclic carbohydrate moiety, specifically inhibits hiv-1 replication while being inactive against hiv-2 or other (retro) viruses. in an attempt to increase the inhibitory efficacy against hiv-1, and to further explore the structural features required for anti-hiv-1 activity, different types of modifications have been carried out on this prototype compound. these include substitution of the ethoxy group at the c-4'' position by alkoxy groups of different length, br ...201121600933
mechanisms of human immunodeficiency virus type 2 rna packaging: efficient trans packaging and selection of rna copackaging partners.human immunodeficiency virus type 2 (hiv-2) has been reported to have a distinct rna packaging mechanism, referred to as cis packaging, in which gag proteins package the rna from which they were translated. we examined the progeny generated from dually infected cell lines that contain two hiv-2 proviruses, one encoding a wild-type gag/gag-pol and the other encoding a mutant gag that cannot express functional gag/gag-pol. viral titers and rna analyses revealed that mutant viral rnas can be packag ...201121613401
hiv-2 a-subtype gp125(c2-v3-c3) mutations and their association with ccr5 and cxcr4 tropism.the early events of the hiv replication cycle involve the interaction between viral envelope glycoproteins and their cellular cd4-chemokine (ccr5/cxcr4) receptor complex. in this study, for the first time, the hiv-2 a-subtype gp125(c2-v3-c3) mutations and their tropism association were characterized by analyzing 149 hiv-2 sequences from the los alamos database. the analysis has strengthened the importance of c2-v3-c3 region as a determinant factor for co-receptor selection. moreover, statistical ...201121814863
acyclic nucleoside thiophosphonates as potent inhibitors of hiv and hbv replication.9-[2-(thiophosphonomethoxy)ethyl]adenine 3 and (r)-9-[2-(thiophosphonomethoxy)propyl]adenine 4 were synthesized as the first thiophosphonate nucleosides bearing a sulfur atom at the a-position of the acyclic nucleoside phosphonates pmea and pmpa. thiophosphonates s-pmea 3 and s-pmpa 4 were evaluated for in vitro activity against hiv-1 (subtypes a to g), hiv-2 and hbv-infected cells, and found to exhibit potent antiretroviral activity. we showed that their diphosphate forms s-pmeapp 5 and s-pmpap ...201121803462
hiv-2 infection surveillance --- united states, 1987--2009.human immunodeficiency virus (hiv) is categorized into two types, hiv-1 and hiv-2. worldwide, most hiv infections are hiv-1, whereas hiv-2 largely has been confined to persons in or from west africa. hiv-1 and hiv-2 have the same routes of transmission, and both can cause acquired immunodeficiency syndrome (aids); however, hiv-2 infections should be differentiated from hiv-1 infections because they are less likely to cause aids and their clinical management differs. cdc's current surveillance ca ...201121796096
variable prevalence and functional diversity of the antiretroviral restriction factor trimcyp in macaca fascicularis.the retroviral restriction factor trimcyp, derived from the trim5 gene, blocks replication at a post-entry step. trimcyp has so far been found in four species of asian macaques, macaca fascicularis, m. mulatta, m. nemestrina, and m. leonina. m. fascicularis is commonly used as a model for aids research, but trimcyp has not been analyzed in detail in this species. we analyzed the prevalence of trimcyp in samples from indonesia, indochina, the philippines, and mauritius. we found that trimcyp is p ...201121795330
hiv-1 replication in monocyte-derived dendritic cells is stimulated by melarsoprol, one of the main drugs against human african trypanosomiasis.human african trypanosomiasis (hat) is a disease caused by the protozoan parasite trypanosoma brucei, the causative agent of sleeping sickness that is still endemic in well defined regions of sub-saharan africa. co-infections with this human pathogen and human immunodeficiency virus (hiv) are not uncommon, but their potential interaction has been little studied. the organo-arsenical drug melarsoprol has been widely used for the treatment of late stage trypanosomiasis since the early 1950s and is ...201121763506
a single amino acid of human immunodeficiency virus type 2 capsid protein affects conformation of two external loops and viral sensitivity to trim5+¦.we previously reported that human immunodeficiency virus type 2 (hiv-2) carrying alanine or glutamine but not proline at position 120 of the capsid protein (ca) could grow in the presence of anti-viral factor trim5+¦ of cynomolgus monkey (cm). to elucidate details of the interaction between the ca and trim5+¦, we generated mutant hiv-2 viruses, each carrying one of the remaining 17 possible amino acid residues, and examined their sensitivity to cm trim5+¦-mediated restriction. results showed tha ...201121829511
sero-prevalence of hiv infection among tuberculosis patients in a rural tuberculosis referral clinic in northern nigeria.co-infection with human immunodeficiency virus (hiv) and mycobacterium tuberculosis the causative agent of tuberculosis (tb), has been referred to as the "cursed duet" as a result of the attendant morbidity and mortality due to their synergistic actions. this study was carried out to determine the prevalence of hiv infection among tuberculosis (tb) confirmed patients on admission at a tb referral centre. the association of hiv prevalence with gender and age as risk factors was also determined. b ...201021293749
cell-associated viral burden provides evidence of ongoing viral replication in aviremic hiv-2-infected patients.viremia is significantly lower in hiv-2 than in hiv-1 infection, irrespective of disease stage. nevertheless, the comparable proviral dna burdens observed for these two infections indicate similar numbers of infected cells. here we investigated this apparent paradox by assessing cell-associated viral replication. we found that untreated hiv-1-positive (hiv-1(+)) and hiv-2(+) individuals, matched for cd4 t cell depletion, exhibited similar gag mrna levels, indicating that significant viral transc ...201021159859
seroprevalence of hcv and its co-infection with hbv and hiv among liver disease patients of south tamil nadu.to determine the seroprevalence of hepatitis c virus (hcv) and its co-infection with hepatitis b virus (hbv), hepatitis delta agent (hdv) and human immunodeficiency virus (hiv) among liver disease patients of south tamil nadu.201021160955
immune responses of mice to prime-boost vaccination with the recombinant dna and fowlpox virus both expressing hiv-2 gag-gp105.human immunodeficiency viruses 1 and 2 (hiv-1, 2) present a public health problem for which there is neither an effective antiviral therapy nor a preventive vaccine. in this study, the immune responses of mice to prime-boost vaccination with the recombinant dna (rdna) and recombinant fowlpox virus (rfpv) both expressing hiv-2 gag-gp105 chimeric protein, were compared to those elicited by each vector alone. mice primed with the rdna and boosted with the rfpv showed hiv-2-specific antibody levels, ...201021175253
restrictions to cross-species transmission of lentiviral infection gleaned from studies of fiv.more than 40 species of primates and over 20 species of cats harbor antibodies that sero-react to lentiviral antigens. in nearly all cases where viral genetic analysis has been conducted, each host species is infected with a unique lentivirus. though lentivirus clades within a species can be substantially divergent, they are typically monophyletic within that species. a notable significant departure from this observation is apparent cross-species transmission of fiv between bobcats (lynx rufus) ...201019896218
direct relationship between virus load and systemic immune activation in hiv-2 infection.immune activation is a hallmark of disease progression in human immunodeficiency virus (hiv) type 1 (hiv-1) and hiv type 2 (hiv-2) infection. however, the relationship between viremia and systemic immune activation is unclear. we assessed the relationship between hiv-2 plasma virus load and immune system activation in a cross-sectional study in a community cohort of hiv-1-positive, hiv-2-positive, and hiv-negative patients, in which many hiv-2-positive patients had nonprogressing infection. hla- ...201019938978
[human immunodeficiency virus type 1, type 2 (hiv-1, hiv-2)]. 201020942107
coreceptor usage by hiv-1 and hiv-2 primary isolates: the relevance of ccr8 chemokine receptor as an alternative coreceptor.the human immunodeficiency virus replication cycle begins by sequential interactions between viral envelope glycoproteins with cd4 molecule and a member of the seven-transmembrane, g-protein-coupled, receptors' family (coreceptor). in this report we focused on the contribution of ccr8 as alternative coreceptor for hiv-1 and hiv-2 isolates. we found that this coreceptor was efficiently used not only by hiv-2 but particularly by hiv-1 isolates. we demonstrate that cxcr4 usage, either alone or toge ...201020947116
simian immunodeficiency virus from the sooty mangabey and rhesus macaque is modified with o-linked carbohydrate.although stretches of serine and threonine are sometimes sites for o-linked carbohydrate attachment, specific sequence and structural determinants for o-linked attachment remain ill defined. the gp120 envelope protein of sivmac239 contains a serine-threonine-rich stretch of amino acids at positions 128 to 139. here we show that lectin protein from jackfruit seed (jacalin), which binds to non- and monosialylated core 1 o-linked carbohydrate, potently inhibited the replication of sivmac239. select ...201020962077
enfuvirtide: from basic investigations to current clinical use.drug resistance is a major challenge in the treatment of hiv infection. enfuvirtide is the first entry inhibitor to have been approved for clinical use.201020977403
hiv type 2 in new york city, 2000-2008.antibody cross-reactivity complicates differential diagnosis of human immunodeficiency virus (hiv) type 2 (hiv-2) using standard serologic screening and confirmatory tests for hiv. hiv type 1 (hiv-1) viral load testing does not detect hiv-2. although hiv-2 is, in general, less pathogenic than hiv-1, it can lead to immunosuppression and clinical aids, and there are important differences in the selection of antiretroviral therapy for hiv-2-related immunosuppression that make it imperative to diffe ...201021039219
epidemiology and seroprevalence of human immunodeficiency virus type 2.hiv-2 infection is detected sporadically mostly from the southern states of india. we did a retrospective analysis to find the seroprevalence of hiv-2 in and around delhi. the study included all attendees of an integrated counseling and testing center (ictc) from january 2004 to january 2009. as per naco guidelines, samples showing positive results in three rapid tests were declared hiv-positive. samples that were reactive for hiv-2 were further confirmed by western blot assay. 8.8% (n = 1,938) ...201021051901
a conserved structure within the hiv gag open reading frame that controls translation initiation directly recruits the 40s subunit and eif3.translation initiation on hiv genomic rna relies on both cap and internal ribosome entry site (ires) dependant mechanisms that are regulated throughout the cell cycle. during a unique phenomenon, the virus recruits initiation complexes through rna structures located within gag coding sequence, downstream of the initiation codon. we analyzed initiation complexes paused on the hiv-2 gag ires and revealed that they contain all the canonical initiation factors except eif4e and eif1. we report that e ...201021071421
replication of biotinylated human immunodeficiency viruses.previous work demonstrated recently the adaptation of the escherichia coli biotin ligase bira - biotin acceptor sequence (bas) labeling system to produce human immunodeficiency virus type 1 viruses with biotinylated integrase (nlxin(b)) and matrix (nlxma(b)) proteins (belshan et al., 2009). this report describes the construction of an hiv permissive cell line stably expressing bira (supt1.bira). consistent with the results in the previous report, nlxma(b) replicated similar to wild-type levels a ...201021087640
high prevalence of hiv-1, hiv-2 and other sexually transmitted infections among women attending two sexual health clinics in bissau, guinea-bissau, west africa.the objective was to examine the prevalence of hiv-1, hiv-2 and 10 other sexually transmitted infections (stis), and to explore the relationship between hiv and those stis in women attending two sexual health clinics in bissau, guinea-bissau. in all, 711 women with urogenital problems were included. clinical examination was performed and hiv-1, hiv-2, human t-cell lymphotropic virus (htlv)-1, htlv-2 and syphilis were diagnosed by serology. trichomonas vaginalis was examined using wet mount micro ...201021097735
polymorphisms of hiv-2 integrase and selection of resistance to raltegravir.human immunodeficiency virus type 2 is naturally resistant to some antiretroviral drugs, restricting therapeutic options for patients infected with hiv-2. regimens including integrase inhibitors (ini) seem to be effective, but little data on hiv-2 integrase (in) polymorphisms and resistance pathways are available.201021114823
identification of a critical t(q/d/e)x5adx2(i/l) motif from primate lentivirus vif proteins that regulate apobec3g and apobec3f neutralizing activity.primate lentiviruses are unique in that they produce several accessory proteins to help in the establishment of productive viral infection. the major function of these proteins is to clear host resistance factors that inhibit viral replication. vif is one of these proteins. it functions as an adaptor that binds to the cytidine deaminases apobec3g (a3g) and apobec3f (a3f) and bridges them to a cullin 5 (cul5) and elongin (elo) b/c e3 ubiquitin ligase complex for proteasomal degradation. so far, 1 ...201020592083
human immunodeficiency virus (hiv) type-1, hiv-2 and simian immunodeficiency virus nef proteins.the genomes of all retroviruses encode the gag pol and env structural proteins. human and simian lentiviruses have acquired non-structural proteins among which nef plays a major role in the evolution of viral infection towards an immunodeficiency syndrome. indeed, in the absence of a functional nef gene, primate lentiviruses are far less pathogenic than their wild type counterparts. the multiple protein-protein interactions in which nef is involved all contribute to explain the role played by ne ...201020594957
fundamental difference in the content of high-mannose carbohydrate in the hiv-1 and hiv-2 lineages.the virus-encoded envelope proteins of human immunodeficiency virus (hiv) and simian immunodeficiency virus (siv) typically contain 26 to 30 sites for n-linked carbohydrate attachment. n-linked carbohydrate can be of three major types: high mannose, complex, or hybrid. the lectin proteins from galanthus nivalis (gna) and hippeastrum hybrid (hha), which specifically bind high-mannose carbohydrate, were found to potently inhibit the replication of a pathogenic cloned siv from rhesus macaques, sivm ...201020610711
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