Identification of bovine leukemia virus tax function associated with host cell transcription, signaling, stress response and immune response pathway by microarray-based gene expression analysis.

BACKGROUND: Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis and is closely related to human T-cell leukemia virus type I. The Tax protein of BLV is a transcriptional activator of viral replication and a key contributor to oncogenic potential. We previously identified interesting mutant forms of Tax with elevated (TaxD247G) or reduced (TaxS240P) transactivation effects on BLV replication and propagation. However, the effects of these mutations on functions other than transcriptional activation are unknown. In this study, to identify genes that play a role in the cascade of signal events regulated by wild-type and mutant Tax proteins, we used a large-scale host cell gene-profiling approach. RESULTS: Using a microarray containing approximately 18,400 human mRNA transcripts, we found several alterations after the expression of Tax proteins in genes involved in many cellular functions such as transcription, signal transduction, cell growth, apoptosis, stress response, and immune response, indicating that Tax protein has multiple biological effects on various cellular environments. We also found that TaxD247G strongly regulated more genes involved in transcription, signal transduction, and cell growth functions, contrary to TaxS240P, which regulated fewer genes. In addition, the expression of genes related to stress response significantly increased in the presence of TaxS240P as compared to wild-type Tax and TaxD247G. By contrast, the largest group of downregulated genes was related to immune response, and the majority of these genes belonged to the interferon family. However, no significant difference in the expression level of downregulated genes was observed among the Tax proteins. Finally, the expression of important cellular factors obtained from the human microarray results were validated at the RNA and protein levels by real-time quantitative reverse transcription-polymerase chain reaction and western blotting, respectively, after transfecting Tax proteins into bovine cells and human HeLa cells. CONCLUSION: A comparative analysis of wild-type and mutant Tax proteins indicates that Tax protein exerts a significant impact on cellular functions as diverse as transcription, signal transduction, cell growth, stress response and immune response. Importantly, our study is the first report that shows the extent to which BLV Tax regulates the innate immune response

Visualizing spatiotemporal dynamics of apoptosis after G1 arrest by human T cell leukemia virus type 1 Tax and insights into gene expression changes using microarray-based gene expression analysis.

BACKGROUND: Human T cell leukemia virus type 1 (HTLV-1) Tax is a potent activator of viral and cellular gene expression that interacts with a number of cellular proteins. Many reports show that Tax is capable of regulating cell cycle progression and apoptosis both positively and negatively. However, it still remains to understand why the Tax oncoprotein induces cell cycle arrest and apoptosis, or whether Tax-induced apoptosis is dependent upon its ability to induce G1 arrest. The present study used time-lapse imaging to explore the spatiotemporal patterns of cell cycle dynamics in Tax-expressing HeLa cells containing the fluorescent ubiquitination-based cell cycle indicator, Fucci2. A large-scale host cell gene profiling approach was also used to identify the genes involved in Tax-mediated cell signaling events related to cellular proliferation and apoptosis. RESULTS: Tax-expressing apoptotic cells showed a rounded morphology and detached from the culture dish after cell cycle arrest at the G1 phase. Thus, it appears that Tax induces apoptosis through pathways identical to those involved in G1 arrest. To elucidate the mechanism(s) by which Tax induces cell cycle arrest and apoptosis, regulation of host cellular genes by Tax was analyzed using a microarray containing approximately 18,400 human mRNA transcripts. Seventeen genes related to cell cycle regulation were identified as being up or downregulated \u3e 2.0-fold in Tax-expressing cells. Several genes, including SMAD3, JUN, GADD45B, DUSP1 and IL8, were involved in cellular proliferation, responses to cellular stress and DNA damage, or inflammation and immune responses. Additionally, 23 pro- and anti-apoptotic genes were deregulated by Tax, including TNFAIP3, TNFRS9, BIRC3 and IL6. Furthermore, the kinetics of IL8, SMAD3, CDKN1A, GADD45A, GADD45B and IL6 expression were altered following the induction of Tax, and correlated closely with the morphological changes observed by time-lapse imaging. CONCLUSIONS: Taken together, the results of this study permit a greater understanding of the biological events affected by HTLV-1 Tax, particularly the regulation of cellular proliferation and apoptosis. Importantly, this study is the first to demonstrate the dynamics of morphological changes during Tax-induced apoptosis after cell cycle arrest at the G1 phase

HIV-1 cellular and tissue replication patterns in infected humanized mice.

Humanized mice have emerged as a testing platform for HIV-1 pathobiology by reflecting natural human disease processes. Their use to study HIV-1 biology, virology, immunology, pathogenesis and therapeutic development has served as a robust alternative to more-well developed animal models for HIV/AIDS. A critical component in reflecting such human pathobiology rests in defining the tissue and cellular sites for HIV-1 infection. To this end, we examined the tissue sites for viral infection in bone marrow, blood, spleens, liver, gut, brain, kidney and lungs of human CD34+ hematopoietic stem cell engrafted virus-infected NOD.Cg-Prkdc(scid) Il2rg(tm1Wjl)/SzJ mice. Cells were analyzed by flow cytometry and sorted from species mixtures defined as CD34+ lineage negative progenitor cells, CD14+CD16+ monocyte-macrophages and central, stem cell and effector memory T cells. The cell distribution and viral life cycle were found dependent on the tissue compartment and time of infection. Cell subsets contained HIV-1 total and integrated DNA as well as multi-spliced and unspliced RNA in divergent proportions. The data support the idea that humanized mice can provide a means to examine the multifaceted sites of HIV-1 replication including, but not limited to progenitor cells and monocyte-macrophages previously possible only in macaques and human

Seroprevalencia de pestivirus de rumiantes en ovinos reproductores de una empresa de la sierra central del Perú

The aim of the present study was to determine the prevalence of Bovine Viral Diarrhea Virus (BVDV) and Border Disease virus (BDV) in breeding sheep from a large cooperative farm in the Central highlands of Peru. Blood samples from apparently healthy sheep of 4 years old, both sexes (female = 165; male = 165) were collected for antibodies detection against BVDV and BDV using the virus neutralization test. The 2.1 ± 1.5% (7/330) and 28.5 ± 4.9% (94/330) of breeding sheep had antibodies against BVDV and BDV respectively, with antibodies titers of 1:2 and 1:16. There was significant association between sex and presence of antibodies against BDV (females: 53.3 ± 7.6%; males: 3.6 ± 2.9%) (p\u3c0.05)

El virus de la diarrea viral en bovinos criollos de la Provincia de Melgar, Puno

The prevalence of bovine viral diarrhea virus (BVDV) infection in 347 evaluated was criollo cattle of both sexes and older than 6 months of age in small herds of the province of Melgar, Puno. Serum samples were tested for antibodies against BVDV using the viral neutralization test. The 48.7 ± 0.1% (166/347) of the samples had antibodies against BVDV. Animals carrying on the virus, virus were not detected. Antibodies were detected in all sampled herds and the prevalence varied from 15.7 to 94.1%. Antibodies titers varied from 2 to \u3e256, showing that BVDV infection is widespread in the local cattle population, suggesting the presence of factors promoting the viral distribution such livestock fairs and lack of control for animal movements within the region

Opposing regulation of endolysosomal pathways by long-acting nanoformulated antiretroviral therapy and HIV-1 in human macrophages.

BACKGROUND: Long-acting nanoformulated antiretroviral therapy (nanoART) is designed to improve patient regimen adherence, reduce systemic drug toxicities, and facilitate clearance of human immunodeficiency virus type one (HIV-1) infection. While nanoART establishes drug depots within recycling and late monocyte-macrophage endosomes, whether or not this provides a strategic advantage towards viral elimination has not been elucidated. RESULTS: We applied quantitative SWATH-MS proteomics and cell profiling to nanoparticle atazanavir (nanoATV)-treated and HIV-1 infected human monocyte-derived macrophages (MDM). Native ATV and uninfected cells served as controls. Both HIV-1 and nanoATV engaged endolysosomal trafficking for assembly and depot formation, respectively. Notably, the pathways were deregulated in opposing manners by the virus and the nanoATV, likely by viral clearance. Paired-sample z-scores, of the proteomic data sets, showed up- and down- regulation of Rab-linked endolysosomal proteins. NanoART and native ATV treated uninfected cells showed limited effects. The data was confirmed by Western blot. DAVID and KEGG bioinformatics analyses of proteomic data showed relationships between secretory, mobility and phagocytic cell functions and virus and particle trafficking. CONCLUSIONS: We posit that modulation of endolysosomal pathways by antiretroviral nanoparticles provides a strategic path to combat HIV infection

HIV-1 cellular and tissue replication patterns in infected humanized mice.

Humanized mice have emerged as a testing platform for HIV-1 pathobiology by reflecting natural human disease processes. Their use to study HIV-1 biology, virology, immunology, pathogenesis and therapeutic development has served as a robust alternative to more-well developed animal models for HIV/AIDS. A critical component in reflecting such human pathobiology rests in defining the tissue and cellular sites for HIV-1 infection. To this end, we examined the tissue sites for viral infection in bone marrow, blood, spleens, liver, gut, brain, kidney and lungs of human CD34+ hematopoietic stem cell engrafted virus-infected NOD.Cg-Prkdc(scid) Il2rg(tm1Wjl)/SzJ mice. Cells were analyzed by flow cytometry and sorted from species mixtures defined as CD34+ lineage negative progenitor cells, CD14+CD16+ monocyte-macrophages and central, stem cell and effector memory T cells. The cell distribution and viral life cycle were found dependent on the tissue compartment and time of infection. Cell subsets contained HIV-1 total and integrated DNA as well as multi-spliced and unspliced RNA in divergent proportions. The data support the idea that humanized mice can provide a means to examine the multifaceted sites of HIV-1 replication including, but not limited to progenitor cells and monocyte-macrophages previously possible only in macaques and human

Opposing regulation of endolysosomal pathways by long-acting nanoformulated antiretroviral therapy and HIV-1 in human macrophages.

BACKGROUND: Long-acting nanoformulated antiretroviral therapy (nanoART) is designed to improve patient regimen adherence, reduce systemic drug toxicities, and facilitate clearance of human immunodeficiency virus type one (HIV-1) infection. While nanoART establishes drug depots within recycling and late monocyte-macrophage endosomes, whether or not this provides a strategic advantage towards viral elimination has not been elucidated. RESULTS: We applied quantitative SWATH-MS proteomics and cell profiling to nanoparticle atazanavir (nanoATV)-treated and HIV-1 infected human monocyte-derived macrophages (MDM). Native ATV and uninfected cells served as controls. Both HIV-1 and nanoATV engaged endolysosomal trafficking for assembly and depot formation, respectively. Notably, the pathways were deregulated in opposing manners by the virus and the nanoATV, likely by viral clearance. Paired-sample z-scores, of the proteomic data sets, showed up- and down- regulation of Rab-linked endolysosomal proteins. NanoART and native ATV treated uninfected cells showed limited effects. The data was confirmed by Western blot. DAVID and KEGG bioinformatics analyses of proteomic data showed relationships between secretory, mobility and phagocytic cell functions and virus and particle trafficking. CONCLUSIONS: We posit that modulation of endolysosomal pathways by antiretroviral nanoparticles provides a strategic path to combat HIV infection

Anticuerpos contra el virus de la estomatitis vesicularen sajinos (Tayassu tajacu) de zoocriaderos de Iquitos y Pucallpa

The objetive of this study was to detect antibodies against vesicular stomatitis virus (VSV) collared peccaries in (Tayassu tajacu) from farms of Iquitos and Pucallpa, Peru. Blood samples were collected in animals olders than 6 months of age (pregnant females were not included) from a farm in Iquitos (n = 21) and from four farms in Pucallpa (n = 47), for detection of antibodies against Indiana 1 and New Jersey serotype of VSV by viral neutralization test. No specific antibodies against both serotypes of VSV were detected, indicating that the peccaries were not exposed to VSV, and suggesting absence of the infection in those animals

Diarrea viral bovina y animales portadores del virus en hatos productores de leche de la irrigación de Majes, Arequipa

The objective of this study was to determine the prevalence of bovine viral diarrhea virus (BVDV) and persistently infected (PI) animals in dairy herds located in Majes, Arequipa, Peru. In the first phase, 204 bulk tank milk samples from herds were collected and sent to the local commercial processing plant in Majes for detection of antibodies against BVDV by indirect ELISA test. In the second phase, 286 blood samples from 57 were collected strong positive (Optical Density [OD] ≥ 0.900) for the detection of herds antibodies against BVDV and in PI animals by the indirect and capture ELISAs respectively. In the third phase, blood samples from all animals were collected ranging from 6 to 24 months of age from three herds had at least one PI animal. The prevalence of BVDV in the 204 herds was 98.0 ± 1.9% (200/204), and the level of antibodies ranged from 0.300 to 2.350 OD.The 47.2% (135/286) of serum antibodies against BVDV HAD samples, and samples within the negative, four (2.7%) animals from three herds were PI. later on, additional PI detected animals were present in these three herds, and none of the six (4.0%) developed antibodies against BVDV. In conclusion, the results indicate that BVDV in dairy herds is widespread in Majes, the high level of antibodies Suggests the presence of PI animals in the bovine population and finally, bulk tank milk samples are very useful for antibody detection from milking cows