Expression and serological application of recombinant epitope-repeat protein carrying an immunodominant epitope of Newcastle disease virus nucleoprotein.

The purpose of this study was to develop serodiagnostic test for differentiation of infected from vaccinated animals strategy (DIVA) which accompanies a marker vaccine less immunodominant epitope (IDE) from the nucleoprotein of Newcastle disease virus (NDV) .Recombinant epitope-repeat protein (rERP) genes that encode eight IDE sequence repeats (ETQFLDLMRAVANSMR) by tetra-glycine linker was synthesized. 

Recombinant baculovirus carrying the gene Canine Recombinant Proteins for expressing rERP rERP produced in insect cells. Specificity and sensitivity enzyme-linked immunosorbent assay indirect (ELISA) employing rERP is evaluated

The rERP with a molecular weight of 20 kDa successfully expressed by recombinant baculovirus in an insect-baculovirus system. The rERP is functional antigen as shown by Western blotting. ELISA indirectly employs rERP developed and specificity and sensitivity is determined. ELISA test allows discrimination of NDV-infected sera from vaccinated deletion virus epitopes sera.The preliminary results represent rERP ELISA as a promising diagnostic tool DIVA.

Serological Detection of Citrus tristeza virus with Antibodies Developed with Recombinant Coat Protein.

Specific antibodies to recombinant coat protein (RCP) of the p25 gene Citrus tristeza virus (CTV) was developed in goats and rabbits and subsequently evaluated as a complete kit for the detection of viruses using healthy tissue and CTV-infected. The combination of goat T1 is used as a primer (coating) and C3 as an intermediary rabbit antibody (detecting) RCP react efficiently, with an optical density at 405 nm (OD405) values ​​between 0.250 and 2.000 with a sample from an international collection of diverse isolates of CTV.

CTV isolates tested cause a wide spectrum of disease syndromes in citrus different hosts. OD405 values ​​for healthy tissue that is less than 0,100. Likewise, the combination of goat T1 and rabbit C3 antibody RCP provide consistent results for CTV-positive and -negative samples discrimination when directly compared to Central California Tristeza http://bmp-5.com/ Eradication Agency (CCTEA) antibody used for the large-scale detection of CTV and CTV commercially available serological detection kit.

The combination of goat T1 and rabbit antibodies RCP C3 indicate suitability for large-scale indexing with samples collected in commercial orchard as part of a regular monitoring program this CCTEA. Evaluation included a sample of 301 41 195 commercial orchard of districts 1, 2, and 3. In total, 26 trees (0.063%) were found to be positive for a combination antibody CTV T1 / C3 RCP. 

The results of this study provide evidence that the RCP antibody can be used efficiently for both capture and detection of CTV antigen in two antibody sandwich indirect enzyme-linked immunosorbent assay.