ABSTRACT
Adenovirus dodecahedron is a virus-like particle composed of only two viral proteins of human adenovirus serotype 3 that are responsible for virus attachment and internalization. We show here that this dodecameric particle, devoid of genetic information, efficiently penetrates human cells and can deliver large multimeric proteins such as immunoglobulins.
Subject(s)
Adenoviruses, Human/genetics , Capsid Proteins/metabolism , Capsid/metabolism , Transduction, Genetic , Adenoviruses, Human/metabolism , Animals , Capsid Proteins/genetics , Dimerization , Genetic Vectors , HeLa Cells , Humans , Mice , Microscopy, Confocal , Virion/genetics , Virion/metabolismABSTRACT
A technique was developed with flow cytometry to quantify the two immediate-early proteins ZEBRA and Rta, which are involved in the activation of Epstein-Barr virus replication. We evaluated four monoclonal antibodies on four cell lines (B95-8, RAJI, Namalwa, and P3HR1) with varying levels of expression of these replication-phase antigens. The Namalwa lymphoma cell line was used as a negative control. Four fixation-permeabilization procedures were compared. The preparation of cells with paraformaldehyde and methanol in sequence, and antigen detection with AZ125 and AR 5A9 monoclonal antibodies, were found to be the optimal conditions in these cell lines. Our procedure allowed ZEBRA antigen to be detected in 4.85% of peripheral blood mononuclear cells from a transplant recipient with a lymphoproliferative disease.
Subject(s)
DNA-Binding Proteins/analysis , Fixatives , Formaldehyde , Herpesvirus 4, Human , Immediate-Early Proteins/analysis , Methanol , Polymers , Trans-Activators/analysis , Viral Proteins/analysis , Animals , DNA-Binding Proteins/immunology , Flow Cytometry/methods , Immediate-Early Proteins/immunology , Mice , Mice, Inbred BALB C , Trans-Activators/immunology , Tumor Cells, Cultured , Viral Proteins/immunologyABSTRACT
An oxidase activating complex from the cytosol of bovine neutrophils was purified by immunoaffinity using a monoclonal antibody specific for the 67 kDa cytosolic factor of oxidase activation (p67) and assayed for production of superoxide O2- in a cell-free system. The complex comprised not only p67, but also the second cytosolic factor of 47 kDa (p47) in equivalent amounts. The p47-p67 complex showed a good oxidase activating potency when added to neutrophil membranes in the presence of GTP-gamma-S and arachidonic acid. A ras-related small G protein could not be immunodetected in the p47-p67 activating complex, indicating that the GTP required for oxidase activation in the cell free system bound to a protein that was either present in catalytic amounts in the cytosolic complex or present in sufficient amount in the membrane fraction.
Subject(s)
NADH, NADPH Oxidoreductases/blood , Neutrophils/enzymology , Animals , Blotting, Western , Cattle , Cell-Free System , Chromatography, Affinity , Cytosol/enzymology , Electrophoresis, Polyacrylamide Gel , Molecular Weight , NADH, NADPH Oxidoreductases/isolation & purification , NADPH Oxidases , Superoxides/bloodABSTRACT
The detection of heat-labile enterotoxin by two tests (culture on Y1 cells and GM1-ELISA) has been carried out on strains of E. coli isolated in stools of children with diarrheal disease (220 strains isolated in the Pasteur Institute in Yaoundé, Cameroon, and 133 stool specimens selected in Grenoble). This work was undertaken to determine the frequency of enterotoxigenic E. coli in two different populations. In Yaoundé the isolation rate (6%) is not very high in comparison with other developing countries. It should be observed that some strains belong to enteropathogenic serogroups. In Grenoble results confirm the very low frequency of enterotoxigenic E. coli in industrialized countries.
