Opportunistic Pneumocystis carinii infection in red-bellied tamarins (Saguinus labiatus). (1/168)

P. carinii infection in red-bellied tamarins (Saguinus labiatus), born and maintained in a laboratory breeding colony, was examined by histopathologic examination postmortem. P. carinii cysts were detected in 6 of 10 red-bellied tamarins examined, by using Grocott's, toluidine blue O and immunostaining with avidin-biotin complex using antisera for rat-, simian-, and human-P. carinii. The results obtained from the present studies imply that P. carinii may be an important pathogen in this species.  (+info)

Natural and experimental oral infection of nonhuman primates by bovine spongiform encephalopathy agents. (2/168)

Experimental lemurs either were infected orally with the agent of bovine spongiform encephalopathy (BSE) or were maintained as uninfected control animals. Immunohistochemical examination for proteinase-resistant protein (prion protein or PrP) was performed on tissues from two infected but still asymptomatic lemurs, killed 5 months after infection, and from three uninfected control lemurs. Control tissues showed no staining, whereas PrP was detected in the infected animals in tonsil, gastrointestinal tract and associated lymphatic tissues, and spleen. In addition, PrP was detected in ventral and dorsal roots of the cervical spinal cord, and within the spinal cord PrP could be traced in nerve tracts as far as the cerebral cortex. Similar patterns of PrP immunoreactivity were seen in two symptomatic and 18 apparently healthy lemurs in three different French primate centers, all of which had been fed diets supplemented with a beef protein product manufactured by a British company that has since ceased to include beef in its veterinary nutritional products. This study of BSE-infected lemurs early in their incubation period extends previous pathogenesis studies of the distribution of infectivity and PrP in natural and experimental scrapie. The similarity of neuropathology and PrP immunostaining patterns in experimentally infected animals to those observed in both symptomatic and asymptomatic animals in primate centers suggests that BSE contamination of zoo animals may have been more widespread than is generally appreciated.  (+info)

A novel Epstein-Barr virus-like virus, HV(MNE), in a Macaca nemestrina with mycosis fungoides. (3/168)

Epstein-Barr virus (EBV) infection of humans has been associated with the development of lymphoid malignancies mainly of B-cell lineage, although occasionally T-cell lymphomas have been reported. We describe here the characterization of a novel EBV-like virus (HV(MNE)) isolated from a simian T-cell lymphotropic virus type I/II (STLV-I/II) seronegative pigtailed macaque (Macaca nemestrina) with a cutaneous T-cell lymphoma. Immunohistochemistry studies on the skin lesions demonstrated that the infiltrating cells were of the CD3(+)/CD8(+) phenotype. Two primary transformed CD8(+) T-cell lines were obtained from cultures of peripheral blood mononuclear cells (PBMC) and skin, and, with time, both cell lines became interleukin-2-independent and acquired the constitutive activation of STAT proteins. Polymerase chain reaction analysis of the DNA from the cell lines and tissues from the lymphomatous animal demonstrated the presence of a 536-bp DNA fragment that was 90% identical to EBV polymerase gene sequences, whereas the same DNA was consistently negative for STLV-I/II sequences. Electron microscopy performed on both cell lines, after sodium butyrate treatment, showed the presence of a herpes-like virus that was designated HV(MNE) according to the existing nomenclature. In situ hybridization studies using EBV Epstein-Barr viral-encoded RNA probes showed viral RNA expression in both CD8(+) T-cell lines as well as in the infiltrating CD8(+) T cells of skin-tissue biopsies. Phylogenetic analysis of a 465-bp fragment from the polymerase gene of HV(MNE) placed this virus within the Lymphocryptovirus genus and demonstrated that HV(MNE) is a distinct virus, clearly related to human EBV and other EBV-like herpesviruses found in nonhuman primates.  (+info)

Species-specific TT viruses and cross-species infection in nonhuman primates. (4/168)

Viruses resembling human TT virus (TTV) were searched for in sera from nonhuman primates by PCR with primers deduced from well-conserved areas in the untranslated region. TTV DNA was detected in 102 (98%) of 104 chimpanzees, 9 (90%) of 10 Japanese macaques, 4 (100%) of 4 red-bellied tamarins, 5 (83%) of 6 cotton-top tamarins, and 5 (100%) of 5 douroucoulis tested. Analysis of the amplification products of 90 to 106 nucleotides revealed TTV DNA sequences specific for each species, with a decreasing similarity to human TTV in the order of chimpanzee, Japanese macaque, and tamarin/douroucouli TTVs. Full-length viral sequences were amplified by PCR with inverted nested primers deduced from the untranslated region of TTV DNA from each species. All animal TTVs were found to be circular with a genomic length at 3.5 to 3.8 kb, which was comparable to or slightly shorter than human TTV. Sequences closely similar to human TTV were determined by PCR with primers deduced from a coding region (N22 region) and were detected in 49 (47%) of the 104 chimpanzees; they were not found in any animals of the other species. Sequence analysis of the N22 region (222 to 225 nucleotides) of chimpanzee TTV DNAs disclosed four genetic groups that differed by 36.1 to 50.2% from one another; they were 35.0 to 52.8% divergent from any of the 16 genotypes of human TTV. Of the 104 chimpanzees, only 1 was viremic with human TTV of genotype 1a. It was among the 53 chimpanzees which had been used in transmission experiments with human hepatitis viruses. Antibody to TTV of genotype 1a was detected significantly more frequently in the chimpanzees that had been used in transmission experiments than in those that had not (8 of 28 [29%] and 3 of 35 [9%], respectively; P = 0.038). These results indicate that species-specific TTVs are prevalent in nonhuman primates and that human TTV can cross-infect chimpanzees.  (+info)

TT virus infection in nonhuman primates and characterization of the viral genome: identification of simian TT virus isolates. (5/168)

Newly discovered TT virus (TTV) is widely distributed in human populations. To understand more about the relationship between TTV and its hosts, we tested 400 sera from various nonhuman primates for the presence of TTV DNA by PCR assay. We collected serum samples from 24 different species of nonhuman primates. TTV DNA was determined by PCR with primers designed from the 5'-end region of the TTV genome. Nucleotide sequencing and phylogenetic analysis of viral genomes were also performed. TTV DNA was detected in 87 of 98 (89%) chimpanzees and 3 of 21 (14%) crab-eating macaques. Nucleotide sequences of the PCR products obtained from both animals were 80 to 100% identical between two species. In contrast, the sequences differed from TTV isolates in humans by 24 to 33% at the nucleotide level and 36 to 50% at the amino acid level. Phylogenetic analysis demonstrated that all TTV isolates obtained from simians were distinct from the human TTV isolates. Furthermore, TTV in simians, but not in humans, was classified into three different genotypes. Our results indicate that TTV in simians represents a group different from, but closely related to, TTV in humans. From these results, we tentatively named this TTV simian TTV (s-TTV). The existence of the s-TTV will be important in determining the origin, nature, and transmission of human TTV and may provide useful animal models for studies of the infection and pathogenesis of this new DNA virus.  (+info)

Detection of hepatitis B virus infection in wild-born chimpanzees (Pan troglodytes verus): phylogenetic relationships with human and other primate genotypes. (6/168)

Infection with hepatitis B virus (HBV) was detected by serological testing for HBV surface antigen and by PCR assay for HBV DNA in serum samples from two common chimpanzees (Pan troglodytes subsp. verus) born in West Africa. The complete genome sequences obtained by nucleotide sequencing of overlapping DNA fragments amplified by PCR were compared with HBV variants recovered from other primates and with human genotypes A to F. Both chimpanzee sequences were 3, 182 nucleotides in length, and the surface gene sequence predicted the existence of a, d, and w serological determinants. Neither sequence contained stop codons in the precore region. On phylogenetic analysis, the HBV variants infecting the chimpanzees clustered together with a third chimpanzee HBV isolate independently obtained from an infected captive animal (A. J. Zuckerman, A. Thornton, C. R. Howard, K. N. Tsiquaye, D. M. Jones, and M. R. Brambell, Lancet ii:652-654, 1978), with an overall sequence similarity of >94%. This provides strong evidence for a chimpanzee-specific genotype of HBV which circulates in nature. These findings add to the recent evidence for infection in the wild of other Old and New World primates (gibbon, orangutan, and woolly monkey) with species-specific variants of HBV. There is no evidence for close phylogenetic clustering of variants found so far in primates with any of the established HBV genotypes from humans. With the new evidence for the widespread distribution of HBV in primates, hypotheses for the origins of human infection are reviewed.  (+info)

A novel type D simian retrovirus naturally infecting the Indian Hanuman langur (Semnopithecus entellus). (7/168)

As a simian species, the langurs are not known to harbor simian retroviruses, except for one report on a simian Type D endogenous retrovirus from the spectacled langur (Trachypithecus obscurus) from Malaysia. The present report describes for the first time natural infection of the common Hanuman langur (Semnopithecus entellus) from India by a novel simian retrovirus (SRV). The new SRV is phylogenetically related to but distinct from the three molecularly characterized serotypes, SRV 1-3, of the five known serotypes of SRVs, based on sequence analyses from the 3'orf and env regions of the viral genome. The novel SRV isolated from the Indian Hanuman langur is provisionally named SRV-6.  (+info)

Promiscuity and the primate immune system. (8/168)

The behavioral and ecological factors involved in immune system evolution remain poorly explored. We present a phylogenetic analysis of white blood cell counts in primates to test three hypotheses related to disease risk: increases in risk are expected with group size or population density, exposure to soil-borne pathogens, and mating promiscuity. White blood cell counts were significantly greater in species where females have more mating partners, indicating that the risk of sexually transmitted disease is likely to be a major factor leading to systematic differences in the primate immune system.  (+info)