ABSTRACT
In order to develop monoclonal antibody against Feline infectious peritonitis virus (FIPV) S1 protein, the truncated S1 protein (rS1) was expressed through Escherichia coli and subsequently purified. Then BALB/c mice were immunized with purified rSl. Three hybridoma cell strains, named 2D7,3D8 and 5G1, stably secreting antibodies against rSl were obtained by cell fusion and indirect ELISA screening. The identification of antibody subtype showed that antibody subtypes of 2D7,5G1 and 3d8 strains were IgG2a,IgG2a and IgGl,respectively. And the light chain of those three hybridoma cell strains was Kappa. Result of karyotype identification of hybridoma cells showed that the chromosome numbers of those three hybridoma cells were about 102,101 and 103, which was belonged to the karyotype of hybridoma. The titer of ascites antibody for indirect ELISA was 1 : 204 800, and monoclonal antibodies were purified. Moreover, all of 2D7,3D8 and 5G1 could react with rS1 by Western-blot and FIPV in cells by IFA. These data suggest that three monoclonal antibodies against rSl with good activities were ideal materials in the study of early diagnosis of FIPV and the biological function of FIPV in the future.