Bovine viral diarrhea virus Erns protein expressed in Chinese hamster ovary cells and its immunogenicity analysis / 生物工程学报

The aim of this study was to produce Erns protein of bovine viral diarrhea virus (BVDV) by using suspensively cultured CHO cells expression system and to analyze the immunogenicity of the purified Erns protein. In this study, the recombinant eukaryotic expression plasmid pcDNA3.1-BVDV-Erns was constructed based on the gene sequence of BVDV-1 NADL strain. The Erns protein was secreted and expressed in cells supernatant after transfecting the recombinant expression plasmid pcDNA3.1-BVDV-Erns into CHO cells. The expression and purification of the Erns protein was analyzed by SDS-PAGE, the reactivity was determined with anti-His monoclonal antibodies and BVDV positive serum with Western blotting. Immunogenicity analysis of the Erns protein was determined after immunizing New Zealand white rabbits, and the serum antibodies were tested by indirect ELISA (iELISA) and indirect immunofluorescence (IFA). The serum neutralizing titer of the immunized rabbits was determined by virus neutralization test. The concentration of the purified Erns protein was up to 0.886 mg/mL by BCA protein quantification kit. The results showed that the Erns protein could be detected with anti-His monoclonal antibodies and anti-BVDV sera. Serum antibodies could be detected by iELISA on the 7th day post-prime immunization, and the antibody level was maintained at a high titer until the 28th day post-immunization. The antibody titer was 1:128 000. Furthermore, the expression of the Erns protein in BVDV-infected MDBK cells could be detected with immunized rabbits sera by IFA. Moreover, antigen-specific neutralizing antibodies of 2.71 log10 was induced in rabbits. In this study, purified BVDV Erns protein was successfully produced using CHO suspension culture system, and the recombinant protein was proved to have a good immunogenicity, which may facilitate the development of BVD diagnosis method and novel subunit vaccine.

Effect of red blood cell preservation solution on serum agglutination reaction of specific patients / 中国输血杂志

【Objective】 To explore the precautions of pre-transfusion examination in patients with antibodies to erythrocyte protective solution, discrepant ABO blood typing results, and positive unexpected antibodies, so as to ensure the safety of blood transfusion. 【Methods】 The screen cells were divided into two groups according to the presence or absence of washing reagent red blood cells in normal saline. One group had untreated forward typing cells, antibody screening cells and identification panel, and the other group had saline-washed reverse typing cells, antibody screening cells and identification panel. The experiments were carried out by microcolumn gel method, saline medium method and polyamine method to analyze the effect of red blood cell preservation solution on serum agglutination reaction of specific patients. 【Results】 Among the 8 patients, forward typing was AB (+ ) in 1 patient, B (+ ) in 4, and A(+ ) in 3, and the reverse typing were interfered. The plasma of 8 patients agglutinated with unwashed reverse typing cells (saline tube method), screen cells and identification panels (saline tube method plus cassette method), while not agglutinated with the polybrene method. The interference was eliminated as using washed reverse typing cells (salinetube method), screen cells and identification panels (saline tube method plus cassette method). 【Conclusion】 The erythrocyte preservation solution affected patients’ blood group typing, but not affected the outcome of blood transfusion as no adverse reactions occurred.

Generation and immunogenicity evaluation of Senecavirus A virus-like particles / 生物工程学报

To develop Senecavirus A (SVA) virus-like particles (VLPs), a recombinant prokaryotic expression plasmid pET28a-SVA-VP031 was constructed to co-express SVA structural proteins VP0, VP3 and VP1, according to the genomic sequence of the field isolate CH-FJ-2017 after the recombinant proteins were expressed in E .coli system, and purified by Ni+ ion chromatographic method. The SVA VLPs self-assemble with a high yield in vitro buffer. A typical VLPs with an average diameter of 25-30 nm which is similar to native virions by using TEM detection. Animals immunized by SVA VLPs shown that the VLPs induced high titers neutralizing antibodies in Guinea pigs. This study indicated that the VLPs produced with co-expressing SVA structural proteins VP0, VP3 and VP1 in prokaryotic system is a promising candidate and laid an important foundation for the development of a novel SVA VLPs vaccine.