Monoclonal antibodies against NS4B protein of japanese encephalitis virus

Evaluation of a water-soluble adjuvant for the development of monoclonal antibodies against small-molecule compounds*

A water-soluble adjuvant named QuickAntibody (QA) was introduced into the procedure of mouse immunization for the development of hapten-specific monoclonal antibodies (mAbs), using four kinds of pesticides as model compounds. Compared with conventional Freund’s adjuvants, QA treatments offered relatively low but acceptable antiserum titers after three inoculations, gave little adverse effects to the experimental animals, and were preferable in harvesting splenocytes during the steps of cell fusion. Afterwards, hybridomas from the QA group were prepared and screened by both non-competitive and competitive indirect enzyme-linked immunosorbent assays (ELISAs). The efficiency of gaining immune-positive hybridomas was satisfactory, and the resultant mAbs showed sensitivities (half maximal inhibitory concentration (IC50)) of 0.91, 2.46, 3.72, and 6.22 ng/ml to triazophos, parathion, chlorpyrifos, and fenpropathrin, respectively. Additionally, the performance of QA adjuvant was further confirmed by acquiring a high-affinity mAb against okadaic acid (IC50 of 0.36 ng/ml) after three immunizations. These newly developed mAbs showed similar or even better sensitivities compared with previously reported mAbs specific to the corresponding analytes. This study suggested that the easy-to-use adjuvant could be applicable to the efficient generation of highly sensitive mAbs against small compounds.

Monoclonal antibody against M protein of spring viremia of carp virus

M protein of spring viremia of carp virus (SVCV) was expressed in Escherichia coli and then used to immunize BALB/c mice. One monoclonal antibody (5A1) against M protein was generated by fusion of mouse myeloma cell line SP2/0 and spleen lymphocytes from immunized mice. The characterizations of this MAb were confirmed by ELISA (enzyme linked immunosorbent assay), IFA (immunofluorescent assay), and Western blot analysis. All results indicate that MAb 5A1 was specific to SVCV M protein.

Monoclonal antibodies against G protein of spring viremia of carp virus

Part of the G protein (3094-4170 bp) of spring viremia of carp virus (SVCV) was expressed in Escherichia coli and purified by dialysis in our study. Two clones of monoclonal antibodies (MAbs 1H11 and 4B8) against G protein were generated by fusion of mouse myeloma cell line SP2/0 and spleen lymphocytes from part of G protein (3094-4170 bp) immunized mice. The results of ELISA (enzyme-linked immunosorbent assay), IFA (indirect immunofluorescent assay), and Western blot assay further demonstrated the characterizations of the two MAbs. Both 1H11 and 4B8 were specific to SVCV G protein. Ten pairs of synthesized overlapping peptides were used to identify the epitope of the MAbs. The MAbs are useful in the development of SVCV diagnostic methods.

Monoclonal Antibodies Against NS2B of Japanese Encephalitis Virus

Japanese encephalitis (JE) is one of the most important viral encephalitis, caused by the Japanese encephalitis virus (JEV). The function of non-structural protein 2B (NS2B) mostly remains unclear. In our study, NS2B of Japanese encephalitis virus (JEV) was expressed in Escherichia coli and purified by dialysis. After fusing mouse myeloma cell line SP2/0 with spleen lymphocytes from NS2B protein immunized mice, three clones of monoclonal antibodies (MAbs), named 1B9, 3E12, and 4E6, were generated. The specificity and sensitivity of MAbs were demonstrated by ELISA, indirect immunofluorescence assay, and Western blot. These MAbs will be useful in further exploration of the functions of NS2B and the pathogenesis of Japanese encephalitis virus.