effects of human recombinant alpha and gamma and of highly purified natural beta interferons on simian spumavirinae prototype (simian foamy virus 1) multiplication in human cells.the present study demonstrates the inhibitory effect of human recombinant interferons (r-hu-ifn) alpha and gamma, and that of highly purified natural human interferon beta on the replication of simian foamy virus type 1 (sfv1) in human av3-cell cultures. all ifn led to strong inhibition of the sfv1 cytopathic effect. electron microscopy showed a 70 to 95% decrease in viral particles. significant inhibition of virus-associated reverse transcriptase activity was found in supernatant fluids of infe ...19901691523
identification of the simian foamy virus transcriptional transactivator gene (taf).simian foamy virus type 1 (sfv-1), a member of spumavirus subfamily of retroviruses, encodes a transcriptional transactivator that functions to strongly augment gene expression directed by the viral long terminal repeat (ltr). the objective of this study was to identify the viral gene responsible for transactivation. nucleotide sequences between the env gene and the ltr of sfv-1 were determined. the predicted amino acid sequence revealed two large open reading frames (orfs), designated orf-1 (31 ...19911851862
syncytium-forming virus of common marmosets (callithrix jacchus jacchus).this communication describes the isolation and characterization of a new syncytium-forming virus of common marmosets (callithrix jacchus jacchus). the virus, isolated from skin explants and peripheral leukocytes of healthy animals, induced syncytia and subsequent cytolysis of several human, simian, and rodent fibroblastic cultures and induced a carrier state in mixed fibroblastic-epithelial or epithelial cell lines. cytoplasmic and nuclear viral antigen was demonstrated in infected cells by indi ...19816164648
persistent asymptomatic infection of the laboratory mouse by simian foamy virus type 6: a new model of retrovirus latency.simian foamy virus (sfv) type 6, originally isolated from the kidney of a kuru-inoculated chimpanzee, has been adapted to produce an asymptomatic infection in swiss-webster white mice, with virus detected in the kidney and spleen for up to 10 months after intra-peritoneal inoculation, and the presence in some animals of complement-fixing, but not neutralizing, serum antibody. this first successful experimental infection of the laboratory mouse by a representative of the foamy virus group has spe ...19826285859
transcriptional trans activators of human and simian foamy viruses contain a small, highly conserved activation domain.the bel-1 protein of human foamy virus is a potent transcriptional trans activator of its homologous long terminal repeat promoter element. here, we demonstrate that bel-1 can also efficiently activate gene expression when targeted to a heterologous promoter by fusion to the dna-binding motif of the yeast gal4 protein. analysis of a series of deletion mutants of bel-1 generated in this hybrid protein context suggests the presence of a single transcription activation domain that is fully containe ...19938411385
infectious proviral clones of chimpanzee foamy virus (sfvcpz) generated by long pcr reveal close functional relatedness to human foamy virus.infectious proviral clones of simian foamy virus isolated from chimpanzee (sfvcpz) were generated by long pcr. two overlapping fragments representing the complete provirus were amplified from genomic dna of infected cells. four 8.8-kbp amplimers extending from base 1 of the provirus into the env gene and five 4.45-kbp amplimers reaching from env to the end of the 3'-ltr were cloned into pcr ii. subsequently, the proviral fragments were combined in a chessboard manner to generate 20 plasmids cont ...19958553577
generation of herpes virus saimiri-transformed t-cell lines from macaques is restricted by reactivation of simian spuma viruses.herpes virus saimiri (hvs) transforms human t-cells in vitro to stable growth. these t-cell lines retain their immunological characteristics of the parent cells and do not release infectious virus. recently, lymphocytes of old world monkeys were efficiently transformed by hvs. in parallel to these studies we initiated transformation experiments by infecting peripheral blood cell cultures of 45 monkeys, 35 rhesus and 10 cynomolgus macaques. in only three cases, we obtained transformed t-cell line ...19979123851
characterization of provirus clones of simian foamy virus type 1.we have cloned proviral dna of simian foamy virus type 1 (sfv-1) from linear unintegrated dna (psfv-1). transfection of psfv-1 induces cytopathology in several cell lines with supernatants from the transfected cell culture containing infectious viral particles. electron microscopy of the transfected cells revealed foamy virus particles. deletion analysis of psfv-1 indicated that the transcriptional transactivator (tas) gene located between env and the long terminal repeat is critical for virus r ...19989420293
simian foamy virus infection in a blood donor.infections with simian foamy virus (sfv) are widely prevalent in nonhuman primates. sfv infection was confirmed in a worker, occupationally exposed to nonhuman primates, who donated blood after the retrospectively documented date of infection. human-to-human transmission of sfv through transfusion and its pathogenicity have not been studied.200212375661
screening for simian foamy virus infection by using a combined antigen western blot assay: evidence for a wide distribution among old world primates and identification of four new divergent viruses.simian foamy viruses (sfvs) belong to a genetically and antigenically diverse class of retroviruses that naturally infect a wide range of nonhuman primates (nhps) and can also be transmitted to humans occupationally exposed to nhps. current serologic detection of sfv infection requires separate western blot (wb) testing by using two different sfv antigens [sfv(agm) (african green monkey) and sfv(cpz) (chimpanzee)]. however, this method is labor intensive and validation is limited to only small n ...200312758172
prevalence of enzootic simian viruses among urban performance monkeys in indonesia.animal reservoirs are the most important sources of emerging infectious diseases that threaten human populations. global travel and tourism bring ever-increasing numbers of humans into contact with animals, increasing the likelihood of cross species transmission of infectious agents. non-human primates come into contact with humans in a variety of contexts and may harbor infectious agents with zoonotic potential. we investigated the prevalence of infection with enzootic simian viruses among 20 u ...200516359412
characterization of blood-borne transmission of simian foamy virus.simian foamy virus (sfv) is an endemic, nonhuman primate (nhp) retrovirus that is transmitted to individuals who work with or hunt nhps. the cross-species transmission of simian retroviruses is believed to be the etiology of human immunodeficiency virus and human t-lymphotropic virus infections in humans. although sfv is not pathogenic in the native host, the shared ancestry with other simian retroviruses has brought into question the potential for acquired pathogenicity after cross-species tran ...200717207245
coinfection of ugandan red colobus (procolobus [piliocolobus] rufomitratus tephrosceles) with novel, divergent delta-, lenti-, and spumaretroviruses.nonhuman primates host a plethora of potentially zoonotic microbes, with simian retroviruses receiving heightened attention due to their roles in the origins of human immunodeficiency viruses type 1 (hiv-1) and hiv-2. however, incomplete taxonomic and geographic sampling of potential hosts, especially the african colobines, has left the full range of primate retrovirus diversity unexplored. blood samples collected from 31 wild-living red colobus monkeys (procolobus [piliocolobus] rufomitratus te ...200919692478
on the general theory of the origins of retroviruses.the order retroviridae comprises viruses based on ribonucleic acids (rna). some, such as hiv and htlv, are human pathogens. newly emerged human retroviruses have zoonotic origins. as far as has been established, both repeated infections (themselves possibly responsible for the evolution of viral mutations (vm) and host adaptability (ha)); along with interplay between inhibitors and promoters of cell tropism, are needed to effect retroviral cross-species transmissions. however, the exact modus op ...201020158888
two distinct variants of simian foamy virus in naturally infected mandrills (mandrillus sphinx) and cross-species transmission to humans.each of the pathogenic human retroviruses (hiv-1/2 and htlv-1) has a nonhuman primate counterpart, and the presence of these retroviruses in humans results from interspecies transmission. the passage of another simian retrovirus, simian foamy virus (sfv), from apes or monkeys to humans has been reported. mandrillus sphinx, a monkey species living in central africa, is naturally infected with sfv. we evaluated the natural history of the virus in a free-ranging colony of mandrills and investigated ...201021156043
phylogenetic analysis of primate foamy viruses by comparison of pol sequences.the relationship between primate foamy viruses was determined by comparing a 425-bp dna segment obtained by pcr using primers homologous to highly conserved portions of the pol gene. the phylogenetic tree of 14 foamy viruses investigated reflects the relationship between their host species: a cluster of asian old world monkey foamy viruses including simian foamy virus (sfv) prototypes 1 and 2 (isolated from macaca cyclopsis) is separated from african old world foamy viruses including prototype s ...19957886963
frequent foamy virus infection in free-living chimpanzees of the taï national park (côte d'ivoire).foamy viruses are frequently found in non-human primates and apes in captivity. however, data on simian foamy virus (sfv) infection in apes from the wild are limited. necropsy specimens were collected from 14 west african chimpanzees (pan troglodytes verus) from three communities in the taï national park, côte d'ivoire. pcr analysis revealed sfv-related int- and env-specific sequences in 12/14 chimpanzees. two young chimpanzees were not infected. plasma from 'pcr-positive' chimpanzees reacted ag ...200919141461
foamy virus vectors: an awaited alternative to gammaretro- and lentiviral vectors.the first vectors derived from foamy viruses were established over ten years ago. until now only used and further developed by a handful of investigators these vectors have been shown to be promising tools for the gene transfer into haematopoietic stem cells. several inherent features of foamy virus-derived vectors, such as the high efficiency in targeting cd34-positive stem cells, a favourable integration profile, and the apathogenic nature of the parental virus, indicate that they are superior ...200717969559
sensitive assays for simian foamy viruses reveal a high prevalence of infection in commensal, free-ranging asian monkeys.foamy viruses (fv) are retroviruses that naturally infect many hosts, including most nonhuman primates (nhps). zoonotic infection by primate fv has been documented in people in asia who reported contact with free-ranging macaques. fv transmission in asia is a concern, given abundant human-nhp contact, particularly at monkey temples and in urban settings. we have developed three assays capable of detecting the presence of fv in asian nhp species that are commensal with humans: enzyme-linked immun ...200717475645
transduction of umbilical cord blood cd34+ nod/scid-repopulating cells by simian foamy virus type 1 (sfv-1) vector.foamy viruses are nonpathogenic retroviruses that offer unique opportunities for gene transfer into various cell types including hematopoietic stem cells. we used a simian foamy virus type 1 vector (sfv-1) containing a lacz reporter gene with a titer of 1-5 x 10(6) viral particles/ml that was free of replication-competent retrovirus to transduce human umbilical cord blood cd34+ cells. transduced cd34+ cord blood cells were transplanted into nod/scid mice and plated in serum-free methylcellulose ...200212441067
amplification of simian retroviral sequences from human recipients of baboon liver transplants.investigations into the use of baboons as organ donors for human transplant recipients, a procedure called xenotransplantation, have raised the specter of transmitting baboon viruses to humans and possibly establishing new human infectious diseases. retrospective analysis of tissues from two human transplant recipients with end-stage hepatic disease who died 70 and 27 days after the transplantation of baboon livers revealed the presence of two simian retroviruses of baboon origin, simian foamy v ...19989671210
the simian foamy virus type 1 transcriptional transactivator (tas) binds and activates an enhancer element in the gag gene.simian and human foamy viruses (sfv and hfv) encode a transcriptional transactivator, tas, which governs the levels of viral transcripts initiated by both the promoter in the long terminal repeat (ltr) and the internal promoter (ip) located within the env gene of these viruses. tas-responsive target elements,(tre) ltr in the ltr and (tre) ip in the env gene, are located 5' of the tata box in both viral promoters and function as orientation- and position-independent enhancers. we have identified ...19968794326
characterization of a human lymphoblastoid cell line permanently modified by simian foamy virus type 10.simian spumavirinae serotype, sfv10, of a papio cynocephalus baboon, was used to infect a human lymphoblastoid cell line, lv2. permanent growth and morphological alterations of infected cells occurred, even though no viral particles were detected. evidence for the presence of viral genomes in the modified cell line is provided indirectly from immunological studies and induction experiments followed by coculture procedures. the permanently modified cell line obtained (lv2-fb10) is an interesting ...19872826791
simian foamy virus type 1 is a retrovirus which encodes a transcriptional transactivator.simian foamy viruses, members of the spumavirus subfamily of retroviruses, are found in a variety of nonhuman primates and, as yet, remain to be characterized with respect to genetic structure and regulation of viral gene expression. the genome of simian foamy virus type 1 (sfv-1), an isolate from rhesus macaques, has been molecularly cloned, and the role of the viral long terminal repeat (ltr) in transcriptional control has been investigated. the sfv-1 ltr is 1,621 base pairs long, and sequence ...19902370676
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