Seronegative human T-cell lymphotropic virus 1 carriers in blood banks: A potential viral source for silent transmission?

Background and Objectives: Transfusion-transmitted viruses count among the greatest threats to blood safety. In Argentina, current laws oblige testing all donated blood for the presence of antibodies against human T-cell lymphotropic viruses 1 and 2 (HTLV-1/2). In endemic zones of the country, a high rate of seronegative HTLV-1 individuals with clear evidence of infection because of symptoms and/or presence of tax sequences of HTLV-1 and/or IgG anti-Tax antibodies has been recently described. Migration from endemic to nonendemic zones of Argentina is very frequent. Materials and Methods: During a 1-year period, in the blood bank of Córdoba city, we performed molecular screening of all donors who were born in or arose from endemic zones for HTLV-1/2 in Argentina and neighbouring countries. Results: By screening 219 bp of HTLV-1/2 tax gene, 0.6% (2/317) of the blood donors proved to be positive for HTLV-1 tax sequence. One of the donors presented anti-Tax antibodies, demonstrating the transcriptional activity of the tax gene, and the other donor was also positive for LTR and pol gene sequences. The HTLV-1 genetic analysis of the LTR sequence determined that it belonged to the Cosmopolitan subtype HTLV-1aA. Conclusion: These findings suggest potential limitations of some currently approved screening assays for HTLV-1 detection applied in some donor populations and the possibility of an HTLV-1 seronegative carrier state with the potential for silent transmission by blood.Fil: Frutos, Maria Celia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; ArgentinaFil: Blanco, Sebastian. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; Argentina. Fundacion Banco Central de Sangre; ArgentinaFil: Balangero, Marcos Cesar. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; ArgentinaFil: Carrizo, Luis Horacio. Fundacion Banco Central de Sangre; ArgentinaFil: Santos Rocha, Anderson. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; Brasil. Interdisciplinary HTLV Research Group; BrasilFil: Figueiredo Barbosa Stancioli, Edel. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; Brasil. Interdisciplinary HTLV Research Group; BrasilFil: Nates, Silvia Viviana. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; ArgentinaFil: Gallego, Sandra Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; Argentin

Evaluation of the effects of Quercetin and Kaempherol on the surface of MT-2 cells visualized by atomic force microscopy

AbstractThis study investigated the anti-viral effects of the polyphenolic compounds Quercetin and Kaempherol on the release of HTLV-1 from the surface of MT-2 cells. Atomic force microscopy (AFM) was used to scan the surface of the MT-2 cells. MT-2 cells were fixed with 100% methanol on round glass lamina or cleaved mica and dried under UV light and laminar flow. The images were captured on a Multimode equipment monitored by a NanoScope IIId controller from Veeco Instruments Inc operated in tapping mode and equipped with phase-imaging hardware. The images demonstrated viral budding structures 131±57nm in size, indicating profuse viral budding. Interestingly, cell-free viruses and budding structures visualized on the surface of cells were less common when MT-2 was incubated with Quercetin, and no particles were seen on the surface of cells incubated with Kaempherol. In summary, these data indicate that HTLV-1 is budding constantly from the MT-2 cell surface and that polyphenolic compounds were able to reduce this viral release. Biological samples were analyzed with crude cell preparations just after cultivation in the presence of Quercetin and Kaempherol, showing that the AFM technique is a rapid and powerful tool for analysis of antiviral activity of new biological compounds

Surveillance of SARS-CoV-2 immunogenicity: loss of immunodominant HLA-A*02-restricted epitopes that activate CD8+ T cells

Introduction and methodsIn this present work, coronavirus subfamilies and SARS-CoV-2 Variants of Concern (VOCs) were investigated for the presence of MHC-I immunodominant viral peptides using in silico and in vitro tools.ResultsIn our results, HLA-A*02 haplotype showed the highest number of immunodominant epitopes but with the lowest combined prediction score. Furthermore, a decrease in combined prediction score was observed for HLA-A*02-restricted epitopes when the original strain was compared to the VOCs, indicating that the mutations on the VOCs are promoting escape from HLA-A2-mediated antigen presentation, which characterizes a immune evasion process. Additionally, epitope signature analysis revealed major immunogenic peptide loss for structural (S) and non-structural (ORF8) proteins of VOCs in comparison to the Wuhan sequence.DiscussionThese results may indicate that the antiviral CD8+ T-cell responses generated by original strains could not be sufficient for clearance of variants in either newly or reinfection with SARS-CoV-2. In contrast, N epitopes remain the most conserved and reactive peptides across SARS-CoV-2 VOCs. Overall, our data could contribute to the rational design and development of new vaccinal platforms to induce a broad cellular CD8+ T cell antiviral response, aiming at controlling viral transmission of future SARS-CoV-2 variants

Characterization of calcium phosphate coating and zinc incorporation on the porous alumina scaffolds

Bone ingrowth requires materials with the existence of open and interconnected pores with diameters larger than 150 µm for proper circulation of nutrients. Such materials must possess enough mechanical strength to avoid failure whilst offering a bioactive surface for bone regeneration. We have developed porous ceramic alumina scaffold with compressive strength that achieves 3.3 MPa by replication method by using the network structure of cellular polymer foam. However, the biocompatibility of ceramics based on Al2O3 requires further improvement so that it could have strong bonding to natural bone tissue. To address this problem of the interface between alumina and bone, we have developed a novel calcium phosphate with Zn2+ (CaP-Zn) coating onto porous alumina ceramic scaffold by impregnating with calcium phosphate/poly(vinyl alcohol) slurry. The tri-dimensional alumina scaffold coated with CaP-Zn was extensively characterized by SEM, EDS and FTIR

Leptospirosis serosurvey in bovines from Brazilian Pantanal using IGG ELISA with recombinant protein LipL32 and microscopic agglutination test

This investigation was carried out in Brazilian Pantanal: region with important biodiversity. This region's climatic conditions, hydrology and geomorphology as well as the existence of great variety of wild species favor the maintenance of the Leptospira in the environment. The aim of this study was to evaluate IgG ELISA with recombinant protein LipL32 in comparison with microscopic agglutination test (MAT) and additionally contribute to the knowledge of the distribution of the one of most important worldwide zoonotic infection, assessing the seropositivity of bovine leptospirosis in beef cattle herds of Brazilian Pantanal, an important ecological preserved area, where cattle constitute not only the most important economic resource but also the major activity compatible of the conservation of natural resource of the region. Out of 282 samples of cattle serum analyzed, 143 (50.71%) were positive in MAT. The serovar Hardjo (genotypic Hardjoprajitno and Hardjobovis), Wolffi and Ballum showed the largest frequency of reactive samples. In the IgG ELISA rLipL32, 161 samples (57.09%) were positive. This result was higher than obtained by MAT (p<0.001). The sensitivity of the ELISA test was 99.30% and the specificity was 86.33%, based on the MAT. This test was shown to be a more sensitive, specific and accurate test for the diagnosis of bovine leptospirosis compared to the MAT

Molecular detection and phylogeny of bovine viral diarrhea virus 1 among cattle herds from Northeast, Southeast, and Midwest regions, Brazil

Submitted by Nuzia Santos ([email protected]) on 2019-08-27T15:42:26Z No. of bitstreams: 1 Molecular detection and phylogeny of bovine viral.pdf: 581803 bytes, checksum: 67af0bad980784eadc90b9fed2d954f5 (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2019-08-27T15:47:18Z (GMT) No. of bitstreams: 1 Molecular detection and phylogeny of bovine viral.pdf: 581803 bytes, checksum: 67af0bad980784eadc90b9fed2d954f5 (MD5)Made available in DSpace on 2019-08-27T15:47:18Z (GMT). No. of bitstreams: 1 Molecular detection and phylogeny of bovine viral.pdf: 581803 bytes, checksum: 67af0bad980784eadc90b9fed2d954f5 (MD5) Previous issue date: 2019Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Laboratório de Vírus. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Laboratório de Vírus. Belo Horizonte, MG, Brasil / Universidade Federal dos Vales do Jequitinhonha e Mucuri. Faculdade de Medicina. Diamantina, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Laboratório de Vírus. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Laboratório de Vírus. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Laboratório de Vírus. Belo Horizonte, MG, Brasil / Fundação Oswaldo Cruz. Instituto René Rachou. Laboratório de Imunologia de Doenças Virais. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Escola de Veterinária. Departamento de Medicina Veterinária Preventiva. Laboratório de Pesquisa em Virologia Animal. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Laboratório de Virologia Básica e Aplicada. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Laboratório de Vírus. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Laboratório de Vírus. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Laboratório de Vírus. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Laboratório de Vírus. Belo Horizonte, MG, Brasil.We examined the circulating BVDV species and genotypes among cattle herds from Northeast, Southeast, and Midwest regions in Brazil. A total of 77 animals tested positive through standard PCR. Phylogenetic analyses revealed the presence of BVDV-1a, highlighting the need for better surveillance strategies to prevent BVDV spread in the country

Are lipid disorders involved in the predominance of human T-lymphotropic virus-1 infections in women?

Abstract INTRODUCTION : The human T-lymphotropic virus-1 (HTLV-1) is associated with chronic inflammatory diseases such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic inflammatory disease. Disturbances in lipid metabolism are involved in inflammatory and demyelinating diseases. METHODS : Plasma levels of triglycerides, total cholesterol, and fractions of HTLV-1-infected individuals of both sexes with different clinical progressions were determined. RESULTS : Elevated levels of triglyceride and very low-density lipoproteins (VLDL) were exclusively detected in HTLV-1-infected women from asymptomatic and HAM/TSP groups compared with uninfected individuals (p = 0.02). CONCLUSIONS : Elevated triglyceride and VLDL levels in HTLV-1-infected women may be related to the predominance of HAM/TSP in women