При помощи стимуляции in vitro человеческих В-лимфоцитов, выделенных из периферической крови вакцинированного донора, получили новое нейтрализующее человеческое антитело RabD4 против гликопротеина вируса бешенства. Антитело обладало высокой антигенсвязывающей способностью и вируснейтрализующей активностью в отношении вируса бешенства, установленной с помощью флуоресцентного вируснейтрализующего теста.
We generated a novel human neutralizing human mAb RabD4 against rabies virus glycoprotein using in vitro stimulation of human peripheral B cells produced by immunized donor. The human mAb RabD4 showed a high antigen-binding activity and virus-neutralizing activity in the FAVN test with the CVS-11 rabies virus.
We determined the nucleotide and amino acid sequences of variable domains of three new monoclonal antibodies to the glycoprotein of Ebola virus capsid. The framework and hypervariable regions of immunoglobulin heavy and light chains were identified. The primary structures were confirmed using massspectrometry analysis. Immunoglobulin database search showed the uniqueness of the sequences obtained.
Balb/С mice were immunized with recombinant Ebola virus glycoprotein. Following the selection, screening, and cloning of murine hybridomas, we obtained five genetically stable clones of monoclonal antibodies GPE118 (IgG), GPE274 (IgM), GPE325 (IgM), GPE463 (IgM), and GPE534 (IgG). These antibodies were isolated and purified from the ascitic fluid of Balb/С mice using Protein G affinity chromatography (for IgG) and euglobulin precipitation (for IgM). To select at least three candidate antibodies for testing in biological assays as components of an antibody cocktail for the prophylaxis and treatment of hemorrhagic fever, we carried out an immunochemical analysis of the epitope specificity of the isolated antibodies. Based on the data of immunoblotting and sandwich ELISA, it became evident that the epitope recognized by GPE 534 differs from the epitopes recognized by the monoclonal antibodies GPE 118 and GPE 325. The last two antibodies also have different epitope specificity: it follows from the immunoblotting data and from the data on the binding of these antibodies with the intact and oxidized (partly deglycosylated) recombinant glycoprotein. For the biological activity studies and the development of recombinant counterparts, we selected three candidate high-affinity monoclonal antibodies GPE 534, GPE 118, and GPE 325.
BALB/с mice were immunized with recombinant Ebola virus glycoprotein. Following selection, screening and cloning of murine hybridomas we obtained 5 genetically stable clones of monoclonal antibodies GPE118 (IgG), GPE274 (IgM), GPE325 (IgM), GPE463 (IgM), and GPE534 (IgG). These antibodies were isolated and purified from ascitic fluid of BALB/с mice using Protein G affinity chromatography (IgG) and euglobulin precipitation method (IgM). For the selection of at least 3 candidate antibodies to be tested in biological assays as components of an antibody cocktail for the prophylaxis and treatment of hemorrhagic fever, we carried out an immunochemical analysis of epitope specificity of isolated antibodies. Based on immunoblotting and sandwich ELISA data, it became evident that the epitope recognized by GPE 534 is different from GPE 118 and GPE 325 epitopes. The latter two antibodies also have different epitope specificity. It is evidenced from immunoblotting data as well as from binding data of these antibodies with intact and oxidized (partly deglycosylated) recombinant glycoprotein. For the studies of biological activity and the development of recombinant counterparts, we isolated 3 candidate high-affinity monoclonal antibodies GPE 534, GPE 118, and GPE 325.
The monoclonal antibodies to Puumala, Dobrava, Hantaan, and Seoul hantaviruses were obtained using mice. The viruses were known to cause HFRS, and two variants of ELISA were designed. First, Hanta-PUU variant, was constructed using monoclonal antibodies to Puumala virus envelope glycoprotein (G(N):G(C)) for detecting only Puumala virus antigen. The second, Hanta-N variant, was constructed using monoclonal antibodies to Dobrava and Puumala nucleocapsid proteins for detecting four above mentioned hantaviruses. Both Hanta-PUU and Hanta-N assays were reliable in detecting specific hantavirus antigens and the immunogenecity of hantavirus vaccines.
The monoclonal antibodies to Puumala, Dobrava, Hantaan, and Seoul hantaviruses were obtained using mice. The viruses were known to cause HFRS, and two variants of ELISA were designed. First, Hanta-PUU variant, was constructed using monoclonal antibodies to Puumala virus envelope glycoprotein (G N:G C) for detecting only Puumala virus antigen. The second, Hanta-N variant, was constructed using monoclonal antibodies to Dobrava and Puumala nucleocapsid proteins for detecting four above mentioned hantaviruses. Both Hanta-PUU and Hanta-N assays were reliable in detecting specific hantavirus antigens and the immunogenecity of hantavirus vaccines.
The peptide conformation in the context of a protein polypeptide chain is influenced by proximal amino acid residues. However, the mechanisms of this interference remain poorly understood. We studied the conformation of angiotensins 1, 2 and 3, which are produced naturally in a sequential fashion from a precursor protein angiotensinogen and contain an identical peptide core structure. Using the example of angiotensins 1, 2 and 3, it was shown that similar amino acid sequences may have significant conformational differences in various molecules. In order to assess the conformational changes, we developed a panel of high-affinity mouse monoclonal antibodies against angiotensins 1, 2 and 3 and studied their cross-reactivity in indirect and competitive ELISAs. It was found that the conformations of inactive angiotensin1 and the corresponding fragment of angiotensinogen are similar; the same is true for the conformations of active angiotensins 2 and 3, whereas the conformations of homologous fragments in the active and inactive angiotensins differ significantly.
Вопрос о влиянии аминокислотного окружения определенных участков белка на их конформацию остается малоизученным. На примере ангиотензинов 1, 2 и 3 - метаболитов ангиотензиногена, мы показали, что одни и те же аминокислотные последовательности в составе разных молекул могут иметь существенные конформационные различия. С этой целью получены высокоаффинные моноклональные антитела против ангиотензинов 1, 2 и 3 и изучена их кросс-реактивность между разными ангиотензинами и ангиотензиногеном. Сделан вывод о том, что конформации неактивных молекул - ангиотензина 1 и соответствующего участка ангиотензиногена - сходны между собой, конформации активных ангиотензинов 2 и 3 также сходны между собой, тогда как конформации гомологичных участков у активных и неактивных ангиотензинов существенно отличаются.