scholarly journals Identification and Characterization of Avian Retroviruses in Chicken Embryo-Derived Yellow Fever Vaccines: Investigation of Transmission to Vaccine Recipients

2003 ◽  
Vol 77 (2) ◽  
pp. 1105-1111 ◽  
Author(s):  
Althaf I. Hussain ◽  
Jeffrey A. Johnson ◽  
Marcos da Silva Freire ◽  
Walid Heneine
Keyword(s):  
Western Blot ◽  
Yellow Fever ◽  
Pcr Analysis ◽  
Rt Pcr ◽  
Serum Samples ◽  
Rna Sequences ◽  
Western Blot Assay ◽  
Specific Pcr ◽  
Show Evidence

ABSTRACT All currently licensed yellow fever (YF) vaccines are propagated in chicken embryos. Recent studies of chick cell-derived measles and mumps vaccines show evidence of two types of retrovirus particles, the endogenous avian retrovirus (EAV) and the endogenous avian leukosis virus (ALV-E), which originate from the chicken embryonic fibroblast substrates. In this study, we investigated substrate-derived avian retrovirus contamination in YF vaccines currently produced by three manufacturers (YF-vax [Connaught Laboratories], Stamaril [Aventis], and YF-FIOCRUZ [FIOCRUZ-Bio-Manguinhos]). Testing for reverse transcriptase (RT) activity was not possible because of assay inhibition. However, Western blot analysis of virus pellets with anti-ALV RT antiserum detected three distinct RT proteins in all vaccines, indicating that more than one source is responsible for the RTs present in the vaccines. PCR analysis of both chicken substrate DNA and particle-associated RNA from the YF vaccines showed no evidence of the long terminal repeat sequences of exogenous ALV subgroups A to D in any of the vaccines. In contrast, both ALV-E and EAV particle-associated RNA were detected at equivalent titers in each vaccine by RT-PCR. Quantitative real-time RT-PCR revealed 61,600, 348,000, and 1,665,000 ALV-E RNA copies per dose of Stamaril, YF-FIOCRUZ, and YF-vax vaccines, respectively. ev locus-specific PCR testing of the vaccine-associated chicken substrate DNA was positive both for the nondefective ev-12 locus in two vaccines and for the defective ev-1 locus in all three vaccines. Both intact and ev-1 pol sequences were also identified in the particle-associated RNA. To investigate the risks of transmission, serum samples from 43 YF vaccine recipients were studied. None of the samples were seropositive by an ALV-E-based Western blot assay or had detectable EAV or ALV-E RNA sequences by RT-PCR. YF vaccines produced by the three manufacturers all have particles containing EAV genomes and various levels of defective or nondefective ALV-E sequences. The absence of evidence of infection with ALV-E or EAV in 43 YF vaccine recipients suggests low risks for transmission of these viruses, further supporting the safety of these vaccines.

Identification of a gene cluster for cell-surface genes of the SRS superfamily inNeospora caninumand characterization of the novelSRS9gene

Parasitology ◽  
2011 ◽  
Vol 138 (14) ◽  
pp. 1832-1842 ◽  
Author(s):  
V. RISCO-CASTILLO ◽  
V. MARUGÁN-HERNÁNDEZ ◽  
A. FERNÁNDEZ-GARCÍA ◽  
A. AGUADO-MARTÍNEZ ◽  
E. JIMÉNEZ-RUIZ ◽  
...  
Keyword(s):  
Western Blot ◽  
Gene Cluster ◽  
Neospora Caninum ◽  
Pcr Analysis ◽  
Rt Pcr ◽  
Specific Expression ◽  
Initial Characterization ◽  
Hydrophilic Region

SUMMARYHere we present the detection of a gene cluster forNeospora caninumsurface genes, similar to theToxoplasma gondiiSRS9 locus, and the cloning and characterization of the NcSRS9gene. PCR genome walking, using NcBSR4gene as a framework, allows the identification, upstream NcBSR4, of 2 sequences homologous to theSRS5and the Ubiquinol-cytochrome C reductase genes and, downstream NcBSR4, of an ORF of 1191 bp coding for a 396-amino acid polypeptide with 59% similarity to the TgSRS9 antigen. A putative 39-residue signal peptide was found at the NH2-terminus followed by a hydrophilic region, and a potential site for a glycosylphosphatidylinositol anchor at the COOH-terminus. A recombinant NcSRS9 protein was produced and was recognized on a Western blot by a low proportion of sera from a panel of naturally infected cows and calves. In addition, Western blot analysis using polyclonal anti-rNcSRS9 revealed stage-specific expression of NcSRS9 in bradyzoites but not in tachyzoites, and immunohistochemistry on brain from a congenitally infected calf showed NcSRS9 recognition in bradyzoites contained in tissue cysts. However, bradyzoite-specific expression of NcSRS9 could not be proven by immunofluorescence on bradyzoites obtainedin vitroand RT-PCR analysis showed no significant variations of NcSRS9transcripts duringin vitrotachyzoite-bradyzoite switch, probably due to incomplete maturity ofin vitrobradyzoites. Initial characterization of NcSRS9 in this study may lead to further studies for a better understanding ofN. caninumpersistence.

scholarly journals Coexistence of Different Genotypes in the Same Bat and Serological Characterization of Rousettus Bat Coronavirus HKU9 Belonging to a Novel Betacoronavirus Subgroup

2010 ◽  
Vol 84 (21) ◽  
pp. 11385-11394 ◽  
Author(s):  
Susanna K. P. Lau ◽  
Rosana W. S. Poon ◽  
Beatrice H. L. Wong ◽  
Ming Wang ◽  
Yi Huang ◽  
...  
Keyword(s):  
Western Blot ◽  
Nucleotide Variation ◽  
Serum Samples ◽  
Specific Primers ◽  
N Protein ◽  
Specific Pcr ◽  
Serological Characterization ◽  
Roosting Behavior ◽  
Bat Coronavirus

ABSTRACT Rousettus bat coronavirus HKU9 (Ro-BatCoV HKU9), a recently identified coronavirus of novel Betacoronavirus subgroup D, from Leschenault's rousette, was previously found to display marked sequence polymorphism among genomes of four strains. Among 10 bats with complete RNA-dependent RNA polymerase (RdRp), spike (S), and nucleocapsid (N) genes sequenced, three and two sequence clades for all three genes were codetected in two and five bats, respectively, suggesting the coexistence of two or three distinct genotypes of Ro-BatCoV HKU9 in the same bat. Complete genome sequencing of the distinct genotypes from two bats, using degenerate/genome-specific primers with overlapping sequences confirmed by specific PCR, supported the coexistence of at least two distinct genomes in each bat. Recombination analysis using eight Ro-BatCoV HKU9 genomes showed possible recombination events between strains from different bat individuals, which may have allowed for the generation of different genotypes. Western blot assays using recombinant N proteins of Ro-BatCoV HKU9, Betacoronavirus subgroup A (HCoV-HKU1), subgroup B (SARSr-Rh-BatCoV), and subgroup C (Ty-BatCoV HKU4 and Pi-BatCoV HKU5) coronaviruses were subgroup specific, supporting their classification as separate subgroups under Betacoronavirus. Antibodies were detected in 75 (43%) of 175 and 224 (64%) of 350 tested serum samples from Leschenault's rousette bats by Ro-BatCoV HKU9 N-protein-based Western blot and enzyme immunoassays, respectively. This is the first report describing coinfection of different coronavirus genotypes in bats and coronavirus genotypes of diverse nucleotide variation in the same host. Such unique phenomena, and the unusual instability of ORF7a, are likely due to recombination which may have been facilitated by the dense roosting behavior and long foraging range of Leschenault's rousette.

Phenotypic, Genotypic, and Functional Characterization Of AML-Derived Endothelial Cells

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1411-1411
Author(s):  
Russell J Pizzo ◽  
Myra Coppage ◽  
Karen Rosell ◽  
Kimberly Morse ◽  
Jane L. Liesveld
Keyword(s):  
Endothelial Cells ◽  
Western Blot ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Leukemia Cell ◽  
Normal Subjects ◽  
Rt Pcr ◽  
Altered Expression ◽  
Normal Subject

Abstract Background In addition to participation in homing, egress, and transmigration of hematopoietic cells, marrow endothelium also contributes to regulation of hematopoiesis with effects on cell proliferation and survival. Characteristics of marrow—derived endothelial cells from normal subjects have been described (Blood 1994; 84: 10-19), but characterization of endothelial cells in leukemia states is incomplete. Angiogenesis is known to be increased in AML marrows, and circulating endothelial progenitors are increased and correlate with disease status and response to treatment. Furthermore, cytokines secreted by endothelial cells such as vascular endothelial growth factor (VEGF) have been found to serve as growth factors for leukemia, sometimes in a paracrine or autocrine fashion. Despite these findings, inhibition of VEGF with agents such as bevacizumab has not demonstrated clinical anti-leukemia activity. Since our group and others have shown that endothelial cells from multiple vascular beds (human umbilical vein endothelial cells—HUVECs), human microvascular endothelial cells derived from skin (HMEC-1 cell line), and normal subject—derived endothelial cells are able to prevent spontaneous or therapy-induced apoptosis in AML blasts, it is important to understand the phenotype and characteristics of endothelial cells isolated from AML patients to understand their functional roles and to see if they might have an angiogenic gene expression profile as has been described in multiple myeloma (Clin Cancer Res 2009 15:5369). Methods Endothelial cells were purified from marrow aspirates obtained with consent from normal subjects or from newly diagnosed AML patients. Cells were isolated using anti-CD105-PE (BD Bioscience) followed by anti-PE microbead selection (Miltenyi™) or after disruption of marrow spicules with subsequent selection for endothelial cells in endothelial cell selective medium (EGM-2, Lonza). Cells between 2nd and 4th passage were utilized for analysis. Protein expression was determined by flow cytometry, Western blotting, or RT-PCR. Matrigel™ tubule formation and acetyl-LDL expression were determined as per previously published methods, as were adhesion, CFU-L, and transmigration assays. RNASeq was performed by the Functional Genomics Core at the University of Rochester after extraction of polyadenylated RNA from purified total RNA. Conversion to cDNA occurred with the Illumina TruSeq™ preparation kit, and sequencing was accomplished with the Illumina Genome Analyzer IIx. CASAVA software was utilized for analysis. Results Marrow derived endothelial cells from normal and AML subjects express CD105 (endoglin), CD31(PECAM), CD106 (VCAM), CD146 (MCAM), CD54 (ICAM), and CD34. They do not express CD14 nor CD45, and they demonstrate low level expression of CD144 (VE-cadherin). By RT-PCR, they express Tie-2, VEGF, and eNOS (endothelial nitric oxide synthase). They express acetyl-LDL and form tubular structures in Matrigel™. Phosphorylated components of the mTOR and PI3K/Akt pathways were also expressed by Western blot analysis. Culture of AML cells with endothelial cells from both normal and AML subjects supported adhesion, transmigration, and CFU-L outgrowth, but no significant differences were noted in these functions between normal and AML—derived endothelial cells in vitro assays. RNASeq analysis revealed 130 genes significantly up—or down—regulated in AML derived endothelial cells as compared with those derived from normal marrow. Endothelial cells from both sources had a distinct signature from marrow—derived fibroblasts. The genes differentially expressed (p<0.001) were included in biological function categories involving cancer, cell development, cell growth and proliferation, cell signaling, inflammatory response, and cell death and survival. Further pathway analysis revealed upregulation of c-Fos, and this upregulation in AML vs. normal subject derived endothelial cells was confirmed by Western blot analysis. Genes involved in chemotaxis such as CXCL16 were also upregulated. Conclusions AML—derived endothelial cells exhibit similar phenotype and function as their normal marrow—derived counterparts, but genomic analysis suggests a differential signature with altered expression of genes which could play a role in leukemogenesis or leukemia cell maintenance in the marrow microenvironment. Disclosures: No relevant conflicts of interest to declare.

scholarly journals The identification and characterization of a testis-specific cDNA during spermatogenesis

2006 ◽  
Vol 11 (1) ◽  
Author(s):  
Ying Chen ◽  
Jiarui Hu ◽  
Ping Song ◽  
Wuming Gong
Keyword(s):  
Experimental Validation ◽  
Rna Binding ◽  
Pcr Analysis ◽  
Splicing Factors ◽  
Rt Pcr ◽  
Rich Domain ◽  
Pachytene Spermatocytes ◽  
Identification And Characterization

AbstractUsing bioinformatics and experimental validation, we obtained a cDNA (named srsf) which was exclusively expressed in the mouse testes. RT-PCR analysis showed that srsf mRNA was not expressed in the gonad during the sex determination period or during embryogenesis. In developing mouse tests, srsf expression was first detected on post-natal day 10, reached its highest level on day 23, and then reduced to and remained at a moderate level throughout adulthood. In situ hybridization analysis demonstrated that srsf mRNA was expressed in pachytene spermatocytes and round spermatids in the testes. The predicted protein contains one RNA-binding domain (RBD) and a serine-arginine rich domain (RS), which are characterized by some splicing factors of SR family members. These findings indicate that srsf may play a role during spermatogenesis.

scholarly journals Parasite-derived circulating microRNAs as biomarkers for the detection of human Schistosoma japonicum infection

Parasitology ◽  
2019 ◽  
Vol 147 (8) ◽  
pp. 889-896 ◽  
Author(s):  
Yi Mu ◽  
Pengfei Cai ◽  
Remigio M. Olveda ◽  
Allen G. Ross ◽  
David U. Olveda ◽  
...  
Keyword(s):  
Schistosoma Japonicum ◽  
Diagnostic Performance ◽  
Area Under The Curve ◽  
Infection Intensity ◽  
The Philippines ◽  
Pcr Analysis ◽  
Rt Pcr ◽  
Serum Samples ◽  
Sensitivity Specificity ◽  
Pcr Targeting

AbstractNovel tools for early diagnosis and monitoring of schistosomiasis are urgently needed. This study aimed to validate parasite-derived miRNAs as potential novel biomarkers for the detection of human Schistosoma japonicum infection. A total of 21 miRNAs were initially validated by real-time-polymerase chain reaction (RT-PCR) using serum samples of S. japonicum-infected BALB/c mice. Of these, 6 miRNAs were further validated with a human cohort of individuals from a schistosomiasis-endemic area of the Philippines. RT-PCR analysis showed that two parasite-derived miRNAs (sja-miR-2b-5p and sja-miR-2c-5p) could detect infected individuals with low infection intensity with moderate sensitivity/specificity values of 66%/68% and 55%/80%, respectively. Analysis of the combined data for the two parasite miRNAs revealed a specificity of 77.4% and a sensitivity of 60.0% with an area under the curve (AUC) value of 0.6906 (P = 0.0069); however, a duplex RT-PCR targeting both sja-miR-2b-5p and sja-miR-2c-5p did not result in an increased diagnostic performance compared with the singleplex assays. Furthermore, the serum level of sja-miR-2c-5p correlated significantly with faecal egg counts, whereas the other five miRNAs did not. Targeting S. japonicum-derived miRNAs in serum resulted in a moderate diagnostic performance when applied to a low schistosome infection intensity setting.

Valosin-containing protein from the hard tick Haemaphysalis longicornis: effects of dsRNA-mediated HlVCP gene silencing

2007 ◽  
Vol 85 (3) ◽  
pp. 384-394 ◽  
Author(s):  
Damdinsuren Boldbaatar ◽  
Badgar Battsetseg ◽  
Takeshi Hatta ◽  
Takeharu Miyoshi ◽  
Naotoshi Tsuji ◽  
...  
Keyword(s):  
Blood Feeding ◽  
Pcr Analysis ◽  
Hard Tick ◽  
Haemaphysalis Longicornis ◽  
Native Protein ◽  
Rt Pcr ◽  
Future Studies ◽  
Atpase Gene ◽  
A Domains

We report the cloning and characterization of a cDNA encoding the valosin-containing protein (VCP) from the Haemaphysalis longicornis tick (HlVCP). The full-length HlVCP is 2782 bp and codes for 808 amino acids of a deduced protein with a predicted molecular mass of 89.9 kDa. The domain structure analysis revealed that the deduced protein has 2 Walker A domains, 2 Walker B domains, a Cdc48 domain, and a polyQ-binding domain. The mouse anti-HlVCP serum recognized a 97 kDa native protein in the salivary glands, midgut, and synganglion. RT–PCR analysis revealed that the native VCP was expressed throughout the developing stages and in tick organs. HlVCP silencing resulted in a decrease in tick body mass after blood feeding. This study not only contributes to a growing understanding of the ATPase gene family but also lays the groundwork for future studies on protein secretion and host–tick interaction. This study is the first report of the VCP gene from Chelicerata, which include spiders, scorpions, and ticks.

Epidemiological and clinical features of HEV infection: a survey in the district of Foggia (Apulia, Southern Italy)

2013 ◽  
Vol 142 (2) ◽  
pp. 287-294 ◽  
Author(s):  
G. SCOTTO ◽  
D. MARTINELLI ◽  
M. CENTRA ◽  
M. QUERQUES ◽  
F. VITTORIO ◽  
...  
Keyword(s):  
General Population ◽  
Western Blot ◽  
Blood Donors ◽  
Southern Italy ◽  
Hepatitis E ◽  
Hiv Positive ◽  
Italian Population ◽  
Serum Samples ◽  
Western Blot Assay ◽  
Low Prevalence

SUMMARYIn this study we assessed the seroprevalence of hepatitis E virus (HEV) infection in both the Italian population and immigrants from developing countries in Foggia (Apulia, Southern Italy). The seroprevalence of HEV was determined in 1217 subjects [412 (34%) immigrants and 805 Italian subjects (blood donors, general population, HIV-positive, haemodialysis patients)]. Serum samples were tested for anti-HEV and confirmed by Western blot assay; in positive patients HEV RNA and genotype were also determined. There were 8·8% of patients that were positive to anti-HEV, confirmed by Western blot. The prevalence in immigrants was 19·7%, and in Italians 3·9% (blood donors 1·3%, general population 2·7%, HIV-positive patients 2·0%, haemodialysis patients 9·6%). Anti-HEV IgM was found in 38/107 (35·5%) of the anti-HEV-positive serum samples (34 immigrants, four Italians). This study indicates a higher circulation of HEV in immigrants and Italian haemodialysis patients, whereas a low prevalence of HEV antibodies was seen in the remaining Italian population.

Potential application of low-stringency single specific primer-PCR in the identification ofLeptospirain the serum of patients with suspected leptospirosis

2004 ◽  
Vol 50 (12) ◽  
pp. 1073-1079 ◽  
Author(s):  
Márcia Costa Ooteman ◽  
Annamaria Ravara Vago ◽  
Matilde Cota Koury
Keyword(s):  
Diagnostic Tool ◽  
Biological Samples ◽  
Pcr Analysis ◽  
Specific Primer ◽  
Serum Samples ◽  
Specific Pcr ◽  
Preliminary Identification ◽  
Pcr Products ◽  
Genetic Signatures ◽  
Potential Use

In this study we tested the potential use of low-stringency single specific primer-PCR (LSSP-PCR) for genetically typing Leptospira directly from biological samples. Serum samples obtained from 29 patients with clinically suspected leptospirosis were amplified by specific PCR, using the previously selected G1 and G2 primers. The PCR products of approximately 300 bp were subsequently used as a template for LSSP-PCR analysis. We were able to produce genetic signatures from the leptospires present in the human samples, which permitted us to make a preliminary identification of the infective serovar by comparing the LSSP-PCR profiles obtained directly from serum samples with those from reference leptospires. Thus, LSSP-PCR has the potential to become a useful diagnostic tool for identifying leptospires in biological samples without the need for bacteria isolation and culture.Key words: LSSP-PCR, Leptospira.

scholarly journals Enzyme Immunoassay Detection of Antigen-Specific Immunoglobulin G Antibodies in Longitudinal Serum Samples from Patients with Cryptosporidiosis

2001 ◽  
Vol 8 (2) ◽  
pp. 415-423 ◽  
Author(s):  
Jeffrey W. Priest ◽  
Anna Li ◽  
Mohamad Khan ◽  
Michael J. Arrowood ◽  
Patrick J. Lammie ◽  
...  
Keyword(s):  
Western Blot ◽  
Immunoglobulin G ◽  
Protozoan Parasite ◽  
Epidemiologic Studies ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Igg Antibody ◽  
Large Format ◽  
Western Blot Assay ◽  
Wide Range

ABSTRACT Cryptosporidium parvum is a protozoan parasite that causes diarrheal illness in a wide range of mammalian hosts, including humans. Characteristic serum immunoglobulin G (IgG) antibody responses to antigens in the 27- and 17-kDa size ranges have been shown to develop after infection, and several enzyme-linked immunosorbent assay (ELISA) and Western blot assay formats have been used to measure these IgG levels in human serum. Using a collection of serial samples from laboratory-confirmed cryptosporidiosis patients, we compared the results obtained by using two new ELISAs with those obtained with two different Western blot assays. When assayed with the large-format Western blot, 97% of the 67 patients had a demonstrable antibody response on at least one occasion. The Cp23 ELISA correctly identified 93% of the samples that had a 27-kDa response by Western blot and 100% of the negative samples. The Triton antigen ELISA detected 77% of the samples that had a 17-kDa response by Western blot and 88% of the negative samples. The sensitivity of the Triton antigen assay was higher for samples collected between 16 and 92 days after the onset of symptoms (96%). The minigel-format Western blot did not compare favorably with the large-format blot for the detection of antibodies to the 27-kDa antigen (71% sensitivity). A half-life of about 12 weeks was estimated for antibodies to both the 27- and 17-kDa antigens. We believe the Cp23 and Triton antigen ELISAs will be useful in epidemiologic studies of the prevalence ofCryptosporidium infection in the population.

scholarly journals Seroprevalence and molecular characterization of Mycobacterium bovis infection in camels (Camelus dromedarius) in the Delta region, Egypt

2019 ◽  
Vol 12 (8) ◽  
pp. 1180-1187 ◽  
Author(s):  
Yasser F. Elnaker ◽  
Mohmed S. Diab ◽  
Nermin A. Ibrahim ◽  
Attia El-Gedawy ◽  
Rania Samir Zaki ◽  
...  
Keyword(s):  
Mycobacterium Bovis ◽  
Dna Sequences ◽  
Sputum Sample ◽  
Pcr Analysis ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Bacteriological Culture ◽  
Two Samples ◽  
Public Risk

Aim: This study aimed to determine the prevalence rates of Mycobacterium infection in camel sera collected before slaughter and gross lesion tissue collected at postmortem (PM) using enzyme-linked immunosorbent assay (ELISA), bacteriological culture, and polymerase chain reaction (PCR). In addition, serum samples from humans who had occupational contact with camels were tested by ELISA and sputum sample by culture. Materials and Methods: ELISA was performed on serum samples antemortem. In addition, bacteriological culture and PCR were conducted after PM. Tuberculosis infection was identified in humans who had contact with camels using ELISA for serum samples and culture for sputum samples. Results: Tuberculous lesions were detected in 184 of 10,903 camels (1.7%). The ELISA results revealed that of the 184 examined camel serum samples, 124 (67.39%) were positive and all 20 camel serum samples that had no associated tuberculous lesions were negative. Moreover, only one of 48 (2.08%) human serum samples was positive by ELISA. Mycobacterial culture revealed 112 isolates from the 184 examined camel samples (60.87%), while human sputum sample cultures were all negative. PCR analysis identified the mpb70 gene in three of seven randomly tested samples. Conclusion: Gene sequencing was performed on two samples and the sequences were submitted to the National Center for Biotechnology Information GenBank (accession numbers MF990289 and MG59479). A phylogenetic tree was constructed based on the partial DNA sequences of the mpb70 gene; the similarity between the isolates was 98.1%. The similarities between the two isolates and the standard strains of Mycobacterium bovis in GenBank were 98.1% and 100%, respectively. Further investigation on the antemortem detection of M. bovis infection in camels is needed to decrease public risk.

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