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Hwaseong, South Korea

Rheindt F.E.,National University of Singapore | Rheindt F.E.,Harvard University | Christidis L.,Southern Cross University of Australia | Christidis L.,University of Melbourne | And 4 more authors.
Journal of Avian Biology

The Strigopidae are an ancient parrot (Psittaciformes) family consisting of three extant species placed in two genera (Nestor, Strigops) and restricted to New Zealand. Their evolutionary history is clouded because the timing of divergence events within this family has variously been attributed to Pleistocene climate change or much earlier earth-historic events. Here we examine new psittaciform DNA sequence data, and combine them with previously published sequences, to shed light on the poorly understood timing of diversification within the Strigopidae. Using calibrations indirectly derived from both psittaciform and non-psittaciform fossils, our data indicate a Late Pliocene or Early Pleistocene (ca 1.2-3.6 mya) differentiation between the two Nestor species (kea and kaka), possibly in response to shifts in habitat distribution associated with sea level fluctuations. The unique, monotypic, nocturnal and flightless genus Strigops (kakapo) is shown to have diverged from the Nestor lineage probably ca 28-29 mya, coinciding with the potential Oligocene submergence of Zealandia when much of its landmass may have been fragmented into smaller islands, providing a setting for allopatric diversification. © 2013 The Authors. Source

The present study compares diagnosis of avian Borna disease virus (ABV) infection of psittacine birds by Western blot of bornaviral proteins in dried feather stems with the detection of anti-bornaviral protein antibodies to bornaviral proteins in plasma by enzyme-linked immunosorbent assay (ELISA). The detection of ABV proteins P40 and P24 in feather calami by Western blotting was possible even after storage of the dried feathers for several years at ambient temperature. Serological identification of anti-bornaviral antibodies may fail (e.g., in young birds, hatched from infected parents), whereas bornaviral P40 and P24 proteins were detected in feather stems. This failure can last at least 10 months after the birds are hatched. In some older birds (>5 years), ABV protein was only detectable in the brain, but not in some peripheral tissues, suggesting that the immune system had succeeded in removing the infecting ABV from tissues outside the brain. These results show that a combination of feather stem analysis for the presence of bornaviral proteins by Western blot combined with serological detection of anti-bornaviral antibodies by ELISA is the most reliable procedure for the detection of a bornaviral infection. © 2015 The Author(s) Source

Jeong H.-J.,Konkuk University | Song Y.-J.,Konkuk University | Lee S.-W.,Konkuk University | Lee J.-B.,Konkuk University | And 6 more authors.
Clinical and Vaccine Immunology

The principal objectives of this study were to develop autologous antigen-presenting cells (APCs) and to characterize the antigen-specific T-cell responses to the M and N proteins of porcine reproductive and respiratory syndrome virus (PRRSV) by using those APCs in outbred pigs. The orf6 and orf7 genes fused with porcine granulocyte-macrophage colony-stimulating factor (GM-CSF) were cloned into the mammalian expression vector to generate two plasmid DNAs, namely, pcDNA3.1-GM-CSF-PRRSV-M and pcDNA3.1-GMCSF-PRRSV-N. Three of six pigs in two groups were repeatedly immunized with either plasmid DNA construct, and four pigs were used as controls. The recombinant M and N proteins fused with the protein transduction domain (PTD) of the human immunodeficiency virus type 1 transactivator of transcription protein were employed to generate major histocompatibility complex-matched autologous APCs from each pig. The levels of T-cell proliferation and gamma interferon (IFN-γ) synthesis were compared between pigs immunized with the two plasmid DNAs after stimulation of the peripheral blood mononuclear cells (PBMCs) of each pig with the autologous antigen-presenting dendritic cells and PBMCs. Higher levels of T-cell proliferation and IFN-γ synthesis were identified in PBMCs isolated from the pigs immunized with pcDNA3.1-GM-CSF-PRRSV-M than in those isolated from the pigs immunized with pcDNA3.1-GM-CSF-PRRSV-N. By way of contrast, serum antibodies were detected only in pigs immunized with pcDNA3.1-GM-CSF-PRRSV-N. However, no T-cell response or antibody production was detected in the control pigs. These results suggest that the M protein of PRRSV is a more potent T cell-stimulating antigen than the N protein. Nevertheless, it should be emphasized that the N protein substantially induces both cellular and humoral immune responses. The newly developed protocol for generating self APCs may prove effective in further efforts to characterize additional PRRSV proteins involved in the induction of cell-mediated immunity. Copyright © 2010, American Society for Microbiology. All Rights Reserved. Source

Fertilized eggs were obtained from four pairs of sun conures (Aratinga solstitialis) infected with avian bornavirus (ABV) genotype 2, as determined by the sequence of the P24 gene. ABV RNA could be detected in early embryos of all four pairs. ABV RNA also was detected in brain, liver, and eyes of late-stage embryos of one of the pairs (Pair 4) and in blood of a 2-wk-old hatchling of this pair, demonstrating that vertical transmission can occur. ABV RNA could be detected in the liver but not in the brain or eyes of the late-stage embryos of another pair (Pair 3). Although it could be detected in the undeveloped eggs of the female parent and 8-day-old embryos, bornaviral RNA could not be found in the brain and liver of the late-stage embryos or in feathers and blood of young (59-wk-old) hatchlings of a third pair (Pair 2). At 11 wk, ABV RNA could be detected again in feathers and blood of these hatchlings and in the brain of one of the hatchlings of Pair 2 that suddenly died. ABV RNA could however be detected in throat swabs of the 5- and 9-wk-old hatchlings and their parents (Pair 2). Although the continued presence of ABV RNA in feathers and blood below the detection level of the reverse transcription-PCR used cannot be excluded, this result also may be attributable to feeding by the infected parents. Analysis by enzyme-linked immunosorbent assay showed that egg yolks and serum of late-stage embryos contain variable amounts of non-neutralizing antiABV-P40, -P10, -P24, and -P16 antibodies, the ratio of which reflected the antibody ratio in the serum of the female parent. Antibodies against the viral glycoprotein, which are considered neutralizing in mammals, and against ABV RNA polymerase were not detected. Whereas 5-wk-old hatchlings of the pair (Pair 2) that produced ABV RNA-free late-stage embryos were free of anti-ABV antibodies, such antibodies could be detected again in the serum of these hatchlings at 9 wk of age, before the age that bornaviral RNA could again be detected in feathers and blood. At 16 wk, these antibodies became abundant. The finding that late-stage embryos, presumably free of ABV RNA, can be obtained from eggs from infected parents suggests that hand- or foster-raising of such birds may be a method to obtain birnavirus-free offspring from some infected birds. © American Association of Avian Pathologists. Source

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