Simian Immunodeficiency Virus SIVagm Efficiently Utilizes Non-CCR5 Entry Pathways in African Green Monkey Lymphocytes: Potential Role for GPR15 and CXCR6 as Viral Coreceptors.

Unlabelled: African green monkeys (AGM) are natural hosts of simian immunodeficiency virus (SIV), and infection in these animals is generally nonpathogenic, whereas infection of nonnatural hosts, such as rhesus macaques (RM), is commonly pathogenic. CCR5 has been described as the primary entry coreceptor for SIV in vivo, while human-derived CXCR6 and GPR15 also appear to be used in vitro. However, sooty mangabeys that are genetically deficient in CCR5 due to an out-of-frame deletion are infectible with SIVsmm, indicating that SIVsmm can use alternative coreceptors in vivo.

Characterization of simian immunodeficiency virus (SIV) that induces SIV encephalitis in rhesus macaques with high frequency: role of TRIM5 and major histocompatibility complex genotypes and early entry to the brain.

Unlabelled: Although nonhuman primate models of neuro-AIDS have made tremendous contributions to our understanding of disease progression in the central nervous system (CNS) of human immunodeficiency virus type 1 (HIV-1)-infected individuals, each model holds advantages and limitations. In this study, in vivo passage of SIVsmE543 was conducted to obtain a viral isolate that can induce neuropathology in rhesus macaques. After a series of four in vivo passages in rhesus macaques, we have successfully isolated SIVsm804E.

TRIM5 alpha drives SIVsmm evolution in rhesus macaques.

The antagonistic interaction with host restriction proteins is a major driver of evolutionary change for viruses. We previously reported that polymorphisms of the TRIM5α B30.2/SPRY domain impacted the level of SIVsmm viremia in rhesus macaques.

Laser capture microdissection assessment of virus compartmentalization in the central nervous systems of macaques infected with neurovirulent simian immunodeficiency virus.

Nonhuman primate-simian immunodeficiency virus (SIV) models are powerful tools for studying the pathogenesis of human immunodeficiency virus type 1 (HIV-1) in the brain. Our laboratory recently isolated a neuropathogenic viral swarm, SIVsmH804E, a derivative of SIVsmE543-3, which was the result of sequential intravenous passages of viruses isolated from the brains of rhesus macaques with SIV encephalitis. Animals infected with SIVsmH804E or its precursor (SIVsmH783Br) developed SIV meningitis and/or encephalitis at high frequencies.

Development of neurological disease is associated with increased immune activation in simian immunodeficiency virus-infected macaques.

Simian immunodeficiency virus (SIV) infection of macaques can result in central nervous system disorders, such as meningitis and encephalitis. We studied 10 animals inoculated with brain-derived virus from animals with SIV encephalitis. Over half of the macaques developed SIV-induced neurologic disease.

Sequential evolution and escape from neutralization of simian immunodeficiency virus SIVsmE660 clones in rhesus macaques.

Simian immunodeficiency virus (SIV) infection of rhesus macaques has become an important surrogate model for evaluating HIV vaccine strategies. The extreme resistance to neutralizing antibody (NAb) of many commonly used strains, such as SIVmac251/239 and SIVsmE543-3, limits their potential relevance for evaluating the role of NAb in vaccine protection. In contrast, SIVsmE660 is an uncloned virus that appears to be more sensitive to neutralizing antibody.

New Methods of Census Record Linking.

The Minnesota Population Center (MPC) has released linked datasets through its NAPP and IPUMS projects, making them readily accessible to researchers. Prior to the availability of complete count census microdata from the MPC, researchers applied various forms of record-linking software. This essay describes the techniques used in the MPC's linking program and briefly compares this technique with those used by other researchers.

Correction of a carboxyl terminal simian immunodeficiency virus Nef frameshift mutation restores virus replication in macaques.

Previous studies demonstrated that the nef gene is a critical determinant of the pathogenicity of simian immunodeficiency virus (SIV) in macaques. In the present study, we evaluated the effect of a spontaneous frameshift mutation in the C-terminus of the nef gene of the minimally pathogenic SIVsmH4i clone. This clone exhibited a single nucleotide deletion in the nef gene relative to pathogenic SIV clones that resulted in a frameshift and addition of 46 amino acids to the C-terminus of Nef.

Improved survival in rhesus macaques immunized with modified vaccinia virus Ankara recombinants expressing simian immunodeficiency virus envelope correlates with reduction in memory CD4+ T-cell loss and higher titers of neutralizing antibody.

Previous studies demonstrated that immunization of macaques with simian immunodeficiency virus (SIV) Gag-Pol and Env recombinants of the attenuated poxvirus modified vaccinia virus Ankara (MVA) provided protection from high viremia and AIDS following challenge with a pathogenic strain of SIV. Although all animals became infected, plasma viremia was significantly reduced in animals that received the MVA-SIV recombinant vaccines compared with animals that received nonrecombinant MVA. Most importantly, the reduction in viremia resulted in a significant increase in median and cumulative survival.

Adaptive evolution of simian immunodeficiency viruses isolated from 2 conventional-progressor macaques with encephalitis.

Simian immunodeficiency virus-infected macaques may develop encephalitis, a feature more commonly observed in macaques with rapid progressive disease than in those with conventional disease. In this report, an analysis of 2 conventional progressors with encephalitis is described. Phylogenetic analyses of viruses isolated from the cerebrospinal fluid and plasma of both macaques demonstrated compartmentalization.

A rapid progressor-specific variant clone of simian immunodeficiency virus replicates efficiently in vivo only in the absence of immune responses.

A subset of simian immunodeficiency virus (SIV)-infected macaques progresses rapidly to disease with transient SIV-specific immune responses and high viral loads. Unique SIV variants with convergent Env mutations evolve in these rapid progressor (RP) macaques. To address the pathogenic significance of RP-specific variants, we generated infectious molecular clones from the terminal-phase plasma of an RP macaque.

Loss of naïve cells accompanies memory CD4+ T-cell depletion during long-term progression to AIDS in Simian immunodeficiency virus-infected macaques.

Human immunodeficiency virus and simian immunodeficiency virus (SIV) induce a slow progressive disease, characterized by the massive loss of memory CD4+ T cells during the acute infection followed by a recovery phase in which virus replication is partially controlled. However, because the initial injury is so severe and virus production persists, the immune system eventually collapses and a symptomatic fatal disease invariably occurs. We have assessed CD4+ T-cell dynamics and disease progression in 12 SIV-infected rhesus monkeys for nearly 2 years.

Immunodeficiency in the absence of high viral load in pig-tailed macaques infected with Simian immunodeficiency virus SIVsun or SIVlhoest.

Simian immunodeficiency virus (SIV) is known to result in an asymptomatic infection of its natural African monkey host. However, some SIV strains are capable of inducing AIDS-like symptoms and death upon experimental infection of Asian macaques. To further investigate the virulence of natural SIV isolates from African monkeys, pig-tailed (PT) macaques were inoculated intravenously with either of two recently discovered novel lentiviruses, SIVlhoest and SIVsun.

Highly pathogenic SHIVs and SIVs target different CD4+ T cell subsets in rhesus monkeys, explaining their divergent clinical courses.

In contrast to simian immunodeficiency viruses (SIVs), which induce immunodeficiency over a 1- to 3-year period, highly pathogenic simian-human immunodeficiency viruses (SHIVs) cause a complete, irreversible, and systemic depletion of CD4(+) T lymphocytes in rhesus monkeys within weeks of infection. By using small-molecule competitors specific for CCR5 and CXCR4 in ex vivo assays, we found that highly pathogenic SHIV(DH12R) exclusively uses CXCR4 for infection of rhesus peripheral blood mononuclear cells, whereas SIV(mac239) and SIV(smE543) use CCR5 for entry into the same cells. During the period of peak virus production in SHIV(DH12R)- or SHIV(89.

Characterization and comparison of recombinant simian immunodeficiency virus from drill (Mandrillus leucophaeus) and mandrill (Mandrillus sphinx) isolates.

Since simian immunodeficiency virus (SIV) was found to be the source of the human AIDS pandemic, a major goal has been to characterize the diversity of SIV strains in the wild and to assess their potential for crossover into humans. In the present study, SIV was isolated from a seropositive drill (Mandrillus leucophaeus) and three seropositive mandrills (Mandrillus sphinx) by using macaque peripheral blood mononuclear cells (PBMC). Full-length sequences were obtained from a drill and mandrill and designated SIVdrl1FAO and SIVmnd5440, respectively.

Characterization of novel simian immunodeficiency viruses from red-capped mangabeys from Nigeria (SIVrcmNG409 and -NG411).

Two novel simian immunodeficiency virus (SIV) strains from wild-caught red-capped mangabeys (Cercocebus torquatus torquatus) from Nigeria were characterized. Sequence analysis of the fully sequenced SIV strain rcmNG411 (SIVrcmNG411) and gag and pol sequence of SIVrcmNG409 revealed that they were genetically most closely related to the recently characterized SIVrcm from Gabon (SIVrcmGB1). Thus, red-capped mangabeys from distant geographic locations harbor a common lineage of SIV.

Patterns of genomic sequence diversity among their simian immunodeficiency viruses suggest that L'Hoest monkeys (Cercopithecus lhoesti) are a natural lentivirus reservoir.

Recently, we described a novel simian immunodeficiency virus (SIVlhoest) from a wild-caught L'Hoest monkey (Cercopithecus lhoesti) from a North American zoo. To investigate whether L'Hoest monkeys are the natural host for these viruses, we have screened blood samples from 14 wild animals from the Democratic Republic of Congo. Eight (57%) were found to be seropositive for SIV.

Simian immunodeficiency virus (SIV) from sun-tailed monkeys (Cercopithecus solatus): evidence for host-dependent evolution of SIV within the C. lhoesti superspecies.

Recently we reported the characterization of simian immunodeficiency virus (SIVlhoest) from a central African l'hoest monkey (Cercopithecus lhoesti lhoesti) that revealed a distant relationship to SIV isolated from a mandrill (SIVmnd). The present report describes a novel SIV (SIVsun) isolated from a healthy, wild-caught sun-tailed monkey (Cercopithecus lhoesti solatus), another member of the l'hoest superspecies. SIVsun replicated in a variety of human T-cell lines and in peripheral blood mononuclear cells of macaques (Macaca spp.

Characterization of a novel simian immunodeficiency virus (SIV) from L'Hoest monkeys (Cercopithecus l'hoesti): implications for the origins of SIVmnd and other primate lentiviruses.

The human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) appear to have originated by cross-species transmission of simian immunodeficiency virus (SIV) from asymptomatically infected African primates. Few of the SIVs characterized to date efficiently infect human primary lymphocytes. Interesting, two of the three identified to infect such cultures (SIVsm and SIVcpz) have appeared in human populations as genetically related HIVs.

Viral genetic evolution in macaques infected with molecularly cloned simian immunodeficiency virus correlates with the extent of persistent viremia.

Genetic evolution of the simian immunodeficiency virus (SIV) envelope glycoprotein was evaluated in a group of six macaques (Macaca nemestrina) infected with the molecularly cloned, moderately pathogenic SIVsm62d. The extent of envelope evolution was subsequently evaluated within the context of the individual pattern of viremia and disease outcome. Two macaques in this cohort developed AIDS by 1.

Phylogeny and natural history of the primate lentiviruses, SIV and HIV.

Studies of primate lentivirus phylogeny over the past decade have established a minimum of five related, but genetically distinct, groups of simian immunodeficiency virus (SIV), each originating from a different African primate species. The hypothesis that HIV-2 (and SIVmac) arose by cross-species transmission from sooty mangabeys (Cercocebus atys has been strengthened by a more detailed characterization of the SIVsm/SIVmac/HIV-2 group of viruses. SIV from all four subspecies of African green monkeys (SIVagm) have been characterized with an apparent chimeric genome structure of SIVagm from West African green monkeys.

Nucleotide sequence analysis of puma lentivirus (PLV-14): genomic organization and relationship to other lentiviruses.

The complete nucleotide sequence of an isolate of puma lentivirus (PLV-14) was obtained by an inverse polymerase chain reaction (I-PCR) technique and confirmed by conventional PCR. Both methods were used to amplify overlapping regions of proviral DNA, for cloning and sequencing, from genomic DNA isolated from PLV-14 infected Florida puma (Felis concolor coryi) peripheral blood mononuclear cells (PBMC). The provirus has a total length of 9100 nucleotides and the genomic organization of presumed protein coding regions are similar to those seen in other members of the lentivirus family, i.

Immunization with whole inactivated vaccine protects from infection by SIV grown in human but not macaque cells.

Homologous SIVsm stocks were generated by passage of a macaque isolate of SIVsm (SIVsm/E660) in human CEM x 174 cells or macaque peripheral blood mononuclear cells. Macaques were immunized with whole inactivated SIV vaccine consisting of virus generated by transfection of CEM x 174 cells with the SIVsmH4 clone and were challenged with either cell-free stock. Only vaccinees challenged with virus generated in human cells were protected from infection.

Worldwide prevalence of lentivirus infection in wild feline species: epidemiologic and phylogenetic aspects.

The natural occurrence of lentiviruses closely related to feline immunodeficiency virus (FIV) in nondomestic felid species is shown here to be worldwide. Cross-reactive antibodies to FIV were common in several free-ranging populations of large cats, including East African lions and cheetahs of the Serengeti ecosystem and in puma (also called cougar or mountain lion) populations throughout North America. Infectious puma lentivirus (PLV) was isolated from several Florida panthers, a severely endangered relict puma subspecies inhabiting the Big Cypress Swamp and Everglades ecosystems in southern Florida.

Expression of soybean lectin gene deletions in tobacco.

A series of constructs containing the developmentally regulated soybean lectin gene (Le1) were used to transform tobacco plants in order to assess developmental and quantitative regulation conferred by flanking sequences. The largest of the lectin constructs contained approximately 3,000 base pairs (bp) of Le1 5 flanking region and 1,500 bp of the 3 flanking region. The smallest construct contained no 5 flanking region and 194 bp of the 3 flanking region.