[ Objective] To compare the characteristics of monoclonal antibodies against infectious bursal disease virus (IBDV) prepared with two different immunogens, VP2 protein expressed by prokaryotic system and purified IB...[ Objective] To compare the characteristics of monoclonal antibodies against infectious bursal disease virus (IBDV) prepared with two different immunogens, VP2 protein expressed by prokaryotic system and purified IBDV. [Methed] IBDV VP2 gene was amplified by RT-PCR and expressed in a prokaryotic system. The recombinant protein was purified by affinity chromatography. IBDV was pudfied by ultracentrifugation. Balb/c mice were immunized with the purified recombinant protein and IBDV, respectively. The monoclonal antibodies were screened by ELISA. [ Result] Two cell lines secreting antibodies against IBDV VP2 protein were obtained, and their ELISA titers were 1:2 × 10^4. Four cell lines secreting antibodies against I BDV were produced, and their ELISA titers were 1:2× 10^6, 1:6 × 10^4, 1:1× 10^5 and 1:4 × 10^3, respectively. All monoclonal antibodies specifically bound to their own immunogen but did not react with other viruses or proteins. After 10 -20 passages, these cell lines still secreted antibodies stably. [Condusion] The monoclonal antibodies prepared with the recombinant IBDV VP2 protein or purified IBDV can induce immune resoonse in mice. and VP2 soecific monoclonal antibodies can be obtained with VP2 orotein expressed in the Drokarvotic system as immunoQen.展开更多
Background Previous serological studies of human bocavirus(HBoV)1 could not exclude cross-reactivity with the other three HBoVs,particularly HBoV2.Methods To search for genotype-specific antibodies against HBoV1 and H...Background Previous serological studies of human bocavirus(HBoV)1 could not exclude cross-reactivity with the other three HBoVs,particularly HBoV2.Methods To search for genotype-specific antibodies against HBoV1 and HBoV2,the divergent regions(DRs)located on the major capsid protein VP3 were defined through viral amino acid alignment and structure prediction.DR-deduced peptides were used as antigens to harvest corresponding anti-DR rabbit sera.To determine their genotype specificities for HBoV1 and HBoV2,these sera samples were used as antibodies against the antigens VP3 of HBoV1 and HBoV2(expressed in Escherichia coli)in western blotting(WB),enzyme-linked immunosorbent assay(ELISA),and bio-layer interferometry(BLI)assays.Subsequently,the antibodies were evaluated with clinical specimens from pediatric patients with acute respiratory tract infection by indirect immunofluorescence assay(IFA).Results There were four DRs(DR1–4)located on VP3 with different secondary and tertiary structures between HBoV1 and HBoV2.Regarding the reactivity with VP3 of HBoV1 or HBoV2 in WB and ELISA,high intra-genotype cross-reactivity of anti-HBoV1 or HBoV2 DR1,DR3,and DR4,but not anti-DR2,was observed.Genotype-specific binding capacity of anti-DR2 sera was confirmed by BLI and IFA,in which only anti-HBoV1 DR2 antibody reacted with HBoV1-positive respiratory specimens.Conclusion Antibodies against DR2,located on VP3 of HBoV1 or HBoV2,were genotype specific for HBoV1 and HBoV2,respectively.展开更多
文摘[ Objective] To compare the characteristics of monoclonal antibodies against infectious bursal disease virus (IBDV) prepared with two different immunogens, VP2 protein expressed by prokaryotic system and purified IBDV. [Methed] IBDV VP2 gene was amplified by RT-PCR and expressed in a prokaryotic system. The recombinant protein was purified by affinity chromatography. IBDV was pudfied by ultracentrifugation. Balb/c mice were immunized with the purified recombinant protein and IBDV, respectively. The monoclonal antibodies were screened by ELISA. [ Result] Two cell lines secreting antibodies against IBDV VP2 protein were obtained, and their ELISA titers were 1:2 × 10^4. Four cell lines secreting antibodies against I BDV were produced, and their ELISA titers were 1:2× 10^6, 1:6 × 10^4, 1:1× 10^5 and 1:4 × 10^3, respectively. All monoclonal antibodies specifically bound to their own immunogen but did not react with other viruses or proteins. After 10 -20 passages, these cell lines still secreted antibodies stably. [Condusion] The monoclonal antibodies prepared with the recombinant IBDV VP2 protein or purified IBDV can induce immune resoonse in mice. and VP2 soecific monoclonal antibodies can be obtained with VP2 orotein expressed in the Drokarvotic system as immunoQen.
基金supported by the Beijing Natural Science Foundation(7192029)the National Natural Science Foundation of China(82172277)the Beijing Municipal Commission of Health(2060399 PXM2017_026268_00005_00254486).
文摘Background Previous serological studies of human bocavirus(HBoV)1 could not exclude cross-reactivity with the other three HBoVs,particularly HBoV2.Methods To search for genotype-specific antibodies against HBoV1 and HBoV2,the divergent regions(DRs)located on the major capsid protein VP3 were defined through viral amino acid alignment and structure prediction.DR-deduced peptides were used as antigens to harvest corresponding anti-DR rabbit sera.To determine their genotype specificities for HBoV1 and HBoV2,these sera samples were used as antibodies against the antigens VP3 of HBoV1 and HBoV2(expressed in Escherichia coli)in western blotting(WB),enzyme-linked immunosorbent assay(ELISA),and bio-layer interferometry(BLI)assays.Subsequently,the antibodies were evaluated with clinical specimens from pediatric patients with acute respiratory tract infection by indirect immunofluorescence assay(IFA).Results There were four DRs(DR1–4)located on VP3 with different secondary and tertiary structures between HBoV1 and HBoV2.Regarding the reactivity with VP3 of HBoV1 or HBoV2 in WB and ELISA,high intra-genotype cross-reactivity of anti-HBoV1 or HBoV2 DR1,DR3,and DR4,but not anti-DR2,was observed.Genotype-specific binding capacity of anti-DR2 sera was confirmed by BLI and IFA,in which only anti-HBoV1 DR2 antibody reacted with HBoV1-positive respiratory specimens.Conclusion Antibodies against DR2,located on VP3 of HBoV1 or HBoV2,were genotype specific for HBoV1 and HBoV2,respectively.