ABSTRACT
Despite the breakthrough in tumor immunotherapy, immunotherapy still faces many challenges due to the special tumor heterogeneity and immunosuppressive microenvironment of solid tumors, such as low drug concentration and response rate within the tumor. The advantages of nanomedicine are supposed to overcome the problems in traditional immunotherapy and improve the host immune stimulation signals as well as tumor immunotherapy effect. This paper firstly reviews the application status of nanomedicine in enhancing natural anti-tumor immunity and overcoming tumor inhibitory microenvironment. Their research hotspots and future development trend are further disscussed.
ABSTRACT
Prokaryotic expression plasmids carrying N-terminal(1-163aa) and C-terminal(141-306aa) gene of HCoV-NL63 nucleocapsid protein were constructed with pET-30a(+) vector. Consequently, we prepared two purified proteins, Np and Cp, respectively, and established a Western blotting-based line assay (WBLA) for detection of antibodies against HCoV-NL63 using three purified proteins: Np , Cp and Nf, a full-length HCoV-NL63 nucleocapsid protein as previously reported. We detected anti-HCoV-NL63 antibodies among 50 sera samples collected from adult for health-examination by WBLA. The results showed that: 25 (50%), 27 (54%), 36 (72%) of 50 sera were indentified as anti-HCoV-NL63 antibody positive when the antigen was from Nf, Np and Cp, respectively. Among these sera with positive anti-HCoV-NL63 antibody,Cp showed highest antibody positive rate in WBLA,and consistent rates of detection were 64% between Nf and Np, 54% between Nf and Cp, 54% between Np and Cp. Our study provides the foundation for development of HCoV-NL63 serological detection reagents and an experimental tool for immunological research of HCoV-NL63 infection.
Subject(s)
Adult , Humans , Antibodies, Viral , Blood , Blotting, Western , Coronavirus , Chemistry , Allergy and Immunology , Nucleocapsid Proteins , Genetics , Allergy and Immunology , Peptide Fragments , Genetics , Recombinant Proteins , Allergy and Immunology , Serologic TestsABSTRACT
<p><b>OBJECTIVE</b>To prepare streptavidin-tagged hepatitis C virus (HCV) fusion protein and explore its application for the detection of antibody against HCV infection.</p><p><b>METHODS</b>A recombinant plasmid pET-11d-C44P-SA was constructed, which coding a novel HCV diagnostic antigens (C44P) and streptavidin (SA) fusion protein, and the fusion protein was generated with BL21 (DE3) E Coli and identified by Western Blot analysis. Then the fusion protein was purified through the Ni-NTA affinity chromatography and over 90% purity has been achieved. Anti-HCV ELISAs were developed when the fusion protein was used in the biotin-pre-coated microplate or ordinary microplate, and then the sensitivity and specificity of the ELISA were evaluated with confirmed human sera panels.</p><p><b>RESULTS</b>The fusion protein was expressed in high yields and purified successfully, the ELISA detection of anti-HCV with human sera panel indicated that its sensitivity and specificity is higher when SA-tagged HCV antigen (C44P-SA) coated in biotin-pre-coated microplate, compared to C44P or C44P-SA coated in ordinary microplate.</p><p><b>CONCLUSION</b>The sensitivity and specificity of anti-HCV ELISA can be improved when a novel HCV diagnostic antigen fused to SA combined with the biotin- pre-coated microplate. This study laid a foundation for improving the performance of HCV diagnostics.</p>