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G Meulemans

Publications and source records attributed to G Meulemans.

At least 37 records · Page 2Linked to original sources
PubMed1987

Evaluation of the use of monoclonal antibodies to hemagglutinin and fusion glycoproteins of Newcastle disease virus for virus identification and strain differentiation purposes.

Monoclonal antibodies detect evident antigenic variations in NDV HN and F protein. However, the A/PMV-1 viruses can be identified by HI test using a preparation made of the combination of two different monoclonals. A primary evaluation of the pathogenicity of the isolated viruses can be made by HI test using monoclonal antibodies but needs always confirmation using conventional pathogenicity tests.

Antibodies, Monoclonal↗
PubMed1987

The hemagglutinin-neuraminidase (HN) gene of Newcastle disease virus strain Italien (ndv Italien): comparison with HNs of other strains and expression by a vaccinia recombinant.

A cDNA library was constructed with poly(A+) mRNA from cells infected with the virulent Italien NDV strain. A clone that hybridized to the HN gene mRNA was sequenced. A long open reading-frame encodes for a protein of 571 amino acids, with a calculated molecular weight of 61,900, including 13 cysteine residues and six potential glycosylation sites. To define the sequence changes that occurred in the avian paramyxovirus hemagglutinin-neuraminidase (HN) during the evolution of virulence, we have studied the HNs of the virulent Italien NDV strain, the mesovirulent Beaudette strain and the nonvirulent Hitchner strain. The majority of amino acid variations are conservative changes but they cluster at 4 preferential sites in the putative head of HN. The clusters of amino acid substitutions are intimately associated or overlap with regions of HN rich in charged amino acid residues and in cysteines. The latter are conserved not only between HNs from all 3 NDV strains but also between HNs of 4 different paramyxoviruses, NDV, SV 5, Sendai and PI 3. The HN coding sequence was inserted into the genome of vaccinia virus under the control of vaccinia P 7.5 K transcriptional regulatory sequences. Expression of native HN proteins at the surface of recombinant HN vaccinia-infected cells was demonstrated by indirect immunofluorescence with 2 anti-HN monoclonals.

Amino Acid Sequence↗
PubMed1987

Expression at the cell surface of native fusion protein of the Newcastle disease virus (NDV) strain Italien from cloned cDNA.

A cDNA library was constructed with poly(A)+-mRNAs from NDV-Italien infected BHK-21 cells. A clone, that hybridized to the F gene mRNA, was sequenced. A long open reading frame encodes for a protein of 553 amino acids, with a calculated molecular weight of 59,153, consisting of twelve cysteine residues and six potential glycosylation sites. The protein sequence contains a hydrophobic region at the N-terminus of F1 and a presumptive long transmembrane fragment near the C-terminus. Comparison of the F proteins from NDV strains Italien and Australia-Victoria shows that the sequences are very similar, with conservation of most cysteine residues and of the potential glycosylation sites. The F coding sequence was inserted into the genome of vaccinia virus under the control of vaccinia P7.5 transcriptional regulatory sequences. Expression of F protein was demonstrated by indirect immunofluorescence with five anti-F monoclonal antibodies known to react with conformational epitopes.

Amino Acid Sequence↗
PubMed1987

Pathogenicity of antigenic variants of Newcastle disease virus Italian strain selected with monoclonal antibodies.

Antigenic variants of the Italian strain of NDV were selected using monoclonal antibodies directed against the HN and F proteins of Italian virus. Antigenic mapping of the HN and F proteins using variant viruses in cross neutralization tests revealed the presence of at least two different epitopes on HN and four epitopes on F protein. Immunoselected variant viruses were demonstrated to have different intravenous pathogenicity index than the parental Italian virus.

Antibodies, Monoclonal↗
PubMed1986

Antigenic and biological characterization of avian paramyxovirus type 1 isolates from pigeons.

21 A/PMV-1 viruses were isolated from pigeons and characterized using polyclonal and monoclonal antisera in hemagglutination inhibition, seroneutralization and immunoprecipitation studies. Polyclonal and monoclonal antibodies directed against the HN and F proteins of Italien virus reacted with all pigeon isolates showing a close relationship between chicken velogenic and pigeon viruses. Differences in the M.W. of F0, P and M proteins were however observed between pigeon and chicken Italien virus. Marked differences in virulence were recorded among pigeon isolates; these were reflected by great variation in the IVPI of the different strains.

Animals↗
PubMed1986

Monoclonal antibodies to hemagglutinin-neuraminidase and fusion glycoproteins of Newcastle disease virus: relationship between glycosylation and reactivity.

Eighteen hybridoma lines obtained by immunization of mice with Newcastle disease virus (NDV) lentogenic strain La Sota or velogenic strain Italien produced hemagglutinating monoclonal antibodies. The 18 monoclones were divided into four groups according to their reactivity toward native hemagglutinin neuraminidase protein (HN), nonglycosylated HN precursor, and heat-denatured HN blotted on nitrocellulose membranes. Only group II reagents were reactive toward their targets in all conditions tested. They were considered sequence-specific antibodies. Group I antibodies did not require glycosylation but lacked reactivity towards the denatured glycosylated antigen. Monoclonal antibodies from group III recognized only the native HN. Group IV was made up of a single monoclone that lacked reactivity with NDV Italien but recognized the La Sota strain in hemagglutination inhibition and enzyme-linked immunosorbent assays. Five hybridoma lines produced monoclonal antibodies which neutralized viral infectivity but failed to inhibit hemagglutination. One monoclonal antibody obtained after immunization of mice with NDV La Sota showed a low neutralization index versus NDV Italien. Four monoclonal antibodies derived from mice immunized with NDV Italien showed higher neutralization indices towards this strain. Neither the denatured F protein nor its nonglycosylated precursor was reacted against by the five monoclonal antibodies.

Animals↗
PubMed1985

[Cervical tumors].

Explore the source record for details and available documents.

Head and Neck Neoplasms↗
PubMed1983

Isolation of orthoreoviruses from psittacine birds.

Orthoreoviridae were regularly isolated from imported psittacine birds in the absence of other pathogens or in combination with salmonella. These viruses grew in embryonated eggs, in chicken embryo fibroblasts and in hepatic cell cultures. The viral isolates were classified as orthoreoviridae on the basis of their morphological and physico-chemical properties.

Animals↗